IMPROVEMENTS IN ELECTRIC AND GALVANIC INSTRUMENTS AND APPARATUS AND IN THEIR APPLICATION TO LIGHTING AND TO MOTIVEPURPOSES
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, Wwe WILLIAM
EDWARDS STAITE of Lombard Street in the City of London Gentleman and
WILLIAM PETRIE of King Street in the County of Middlesex Gentleman send
greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria by Her
Royal Letters l'atent under the Great Seal of the United Kingdom of Great
Britain and Ireland bearing date at Westminster the Twentieth day of
September One thousand eight hundred and forty-nine in the thirteenth
year of Her reign did for Herself Her heirs and successors give and
grant unto us the said William Edwards Staite and William Petric
or exors admors and assigns Her especial licence full power sole privilege
and authority that we the said William Edwards Staite and William
Petrie our exors admors and assigns or such others as we the said
William Edwards Staite and William Petric our exors admors or assigns
should at any time agree with and no others from time to time and at all times
during the term of years therein expressed should and lawfully might make
use exercise and vend within England Wales and the Town of Berwick-
upon-Tweed, and in the Islands of Guernsey Jersey Alderney Sark and
Man and also in all Her said Majesty's Colonies and Plantations abroad
our Invention of "IMPROVEMENTS IN ELECTRIC AND GALVANIC INSTRUMENTS AND
APPARATUS AND IN THEIR APPLICATION TO LIGHTING AND TO MOTIVE PURPOSES" in
which said Letters Patent is contained a. proviso that we the said. William
Edwards Staite and William Petrie or one of us shall cause a particular
description of the nature of our said Invention and in what manner the same

page_text: is to be performed by an instrument in writing under our hands and seals
or under the hand and seal of one of us to be inrolled in Her Majesty's High
Court of Chancery within six calendar months next and immediately after the
date of the said in part recited Letters Patent reference being thereunto had
will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso we the said
William Edwards Staite and William Petrie hereby declare that the nature
of the said Invention and the manner in which the same is to be performed
are fully described and ascertained in and by the present Specification thereof
reference being had to the Drawings hereunto annexed (that is to say):--
Firstly our Invention consists of certain improved hydro-barometers
applicable to electric and galvanic apparatus. The principal use of these
instruments is to place them in the individual battery cells so that the liquid
supplied to each cell shall drop first into the said instrument and thence pass
through it into the body of liquid in the cell whereby in batteries where each
cell is supplied direct from the reservoir the relative specific gravity of the
liquid in the cell and the liquid supplied can be discerned by inspection and
thence it can be known whether any cell is becoming more exhausted than the
others by reason of an insufficient supply or on the other hand is receiving an
undue share of fresh liquid. A hydro-barometer suitable for liquids (such as
nitric acid or sulphate of copper) which become lighter by being used in the
battery is represented in Figure 1. A glass tube A B rather taller than the
galvanic cell G G G in which it is placed upright is bent round at its
lower end B so that its orifice points upwards. At its upper end it terminates
in a funnel A its stem is graduated with horizontal marks about one eighth of
an inch wide for a short distance above and below the surface of the liquid.
The supply of fresh liquid drops into the funnel top of the tube and the level
of the liquid within the tube will be perceived to be somewhat below thatwhich
is around the tube the amount of difference measured by the graduations
indicates the exhaustion of the liquid in the cell relatively to that in any other
similar cell similarly supplied. For liquids (such as dilute sulphuric acid)
which become heavier by being used in the battery an instrument such as is
represented in Figure 1+ is employed. A glass tube C D E with its upper end
funnel shaped and its stem graduated (similar in fact to the part of the before-
mentioned instrument) extends to the bottom of the cell in which it is placed
and its lower part D is bent round and continues vertically upwards again until
E near the surface of the liquid. There is an orifice at D its lowest part (as
sliewn in the Drawing). The supply of fresh liquid drops into the funnel at
the top of the tube and the liquid within the tube will be observed to stand at

page_text: a slightly higher level than that around the tubewhereby it gives indications as
in the former case (of A B.)
Secondly our Invention consists of a flexible enclosed capillary syphon to
be used with galvanic batteries. It may be made of any of the materials that
are suitable for the arrangement commonly called the capillary syphon such as
lamp wick, woollen material asbestos hair wires &c. such materials being
enclosed in a tube of vulcanized caoutchouc which being waterproof protects
the material from being injured by water or most dilute acids. Holes may be
cut in the parts of the syphon casewhich are uppermost when it is bent in order
to afford a freer exit to any air that may be lodged in it and a wire of copper
or lead may be enclosed in the case to make it retain any bend that may be
given it. The instrument is then used as an ordinary capillary syphon to with-
draw the liquid slowly from either of the upper or lower part of a galvanic
cell and another similar syphon can be used to replenish the same. Those
parts of the syphon which are much beneath the surface of the liquids when
the syphon is in action are to be stuffed very loosely with the capillary material
inside. The particular features of this improvement are that it takes all the
liquid from that part of the cell (such as the bottom) to which the end of the
syphon may be placed whereas ordinary capillary syphons take most of the
liquid from the surface of it even though they may extend below the surface.
Again this capillary syphon also does not wet the sides of the vessels over
which it may pass.
Thirdly for the purpose of protecting instruments or apparatus used for
galvanic batteries or in connection with them which are inade in whole or in
part of iron from the action of acids and for improving their electric insulation
we sulphurise them by a process which is also applicable to most metallic
articles and even to wood and some other materials. The process is as follows:
The article is heated so hot as to freely melt the sulphur when applied to it, a
roll of sulphur is then rubbed slowly over its surface until the whole surface is
dripping wet with melted sulphur. If it be desired to give it a thin coating
only the surplus sulphur is wiped off more or less thoroughly with some tow,
or scraped off with an edge of wood but if a thick coating is required the
article is slowly turned about in all directions (so as to prevent the liquid sul-
phur from running more on one spot than another) until the sulphur, has
begun to solidify upon it. The article is then left until quite cool, when the
sulphur will be found in most cases to form a smooth compact coating, very
adhesive and not so easily chipped off as some kinds of ordinary cement. It
generally assumes a brownish colour. It is advisable in some cases to reheat.
the article or some parts of it once or oftener during the application of the

page_text: sulphur to it. The preceding process is particularly serviceable to protect the
exterior of cast-iron batteries from chemical action and to prevent the electric
power from passing off by the supports which they may stand upon when these
supports are of damp wood-It is also very useful for cast-iron or wooden
channels that may be used to hold or convey nitric acid. We also, not only
coat the interior of battery troughs in this manner, but we fasten porous plates
or slates in the places into which they are fitted by heating the parts and
running melted sulphur down their joints. When an article has become cool
after any of the above-named operations we in some cases take a smoother,
that is, a piece of iron or copper being a conductor of heat having a polished
surface flat or of such other form as will suit the sulphurized surface of the
article; and having heated the said smoother to about a dull red heat we pass
it lightly and quickly over the sulphurized surface. This has the effect of more
perfectly closing up any minute cracks or cavities in the sulphur such as those
which the crystallization or contraction of the sulphur tends to produce during
the process of cooling. The heat of the smoothing instrument induces what is
known as the "brown state" on the surface of the sulphur in which state it is
tough and not liable to have cracks or figures as it cools. If the smoother is
much cooler it may be used without inducing this state. The sulphurized
surface may be painted over in cases which will allow of paint being used.
Fourthly our Invention has relation to the arrangement now commonly
adopted for causing the change in the specific gravity of that solution in the
battery which becomes specificallyheavier bythe action of the battery to effect
the removal of the exhausted or heavy part of the solution and a supply of
fresh solution in its place and consists in the improvements represented in
Figure 2 in which the parts that are old are marked with the letter A. The
solutions to which the said arrangements particularly applies in batteries in
present common use are the solutions used next the zine in double fluid bat-
teries namely dilute sulphuric acid, and solutions of salts with a slight addition
of acid as herein-after explained. With this arrangement it is not necessary
to have space and bulk in the batteryitself to be occupied by a stock of the zinc
solution the cells may therefore be made very compact. The arrangement may
besidesbe applied either to single andseparate cells or to a number of cells con-
nected together as in a single trough with waterproof channels branching from
a main channel to the zinc compartment of each cell. From the channel B in
the bottom of the trough A already referred to as communicating with the zinc
compartment of each cell proceeds a short pipewhich mayhe of lead varnished
inside) to which is attached a bit of vulcanized caoutchouc tube E E which
is connected at its lower end to another pipe FF (preferred to be of varnished

page_text: lead) which last pipe is fixed in the top of a common keg or cask G G which
stands upright on a support at some distance (not less than two and a half or
three times its own height) below the level of the bottoin of the battery
(though it need not necessarily be immediately beneath the battery for it may
be somewhat to one side or other according as a convenient place can be
found for it. It is as well to have the keg cooped with copper hoops instead of
iron which is acted on by dilute acids &c. The pipe F passes through the
head of the keg down to near the bottom inside and is secured by a broad
collar or flange h h fixed to its upper part the collar being screwed down to
the head of the keg with a washer of vulcanized caoutchouc between the collar
and the head of the keg. From the head of the keg and similarly secured to
it arises another short pipe I which does not extend downwards within the
cask; and to it is attached another piece of vulcanized caoutchouc tube KK
which extends upwards and is attached to a short bit of (lead) tube L. which
extends upwards to a short distance above the level of the solution in the
battery and then bends downwards and terminates vertically over a channel C
which is formed in the side of the battery trough A and which has holes or
branch channels below the surface of the liquid that is in it leading to the zine
compartment of the various cells. The said pipe L has an orifice M at the
upper side of the highest part of its bend in order to prevent the bent part
from acting as a syphon and the pipe is held in its position by a supporting
rod N which may be slid up or down in a tube o and set tight by a screw at any
elevation so as to fixthe bend of the tube at anydesired level above the liquid in
the channel C: The difference of level (between M and C) will determine the
degree of exhaustion to which it is desired to work the liquid in the battery,
and will be less in the case of solutions of salts than in the case of dilute sul-
phuric acid of greater solvent power being used. When the battery is charged
the keg (G) is necessarily filled with solution as well as the zinc compartments
in the battery, so that when the battery begins to work a portion of the solution
as it dissolves the zinc and becomes specifically heavier falls to the bottom of
the cells and descends into the bottom of the cask through the channel B and
tubes D. E. F. The superior hydrostatic pressure of this denser liquid in the
Tubes D. E. F. causes the liquid in K to arise above the level (of C) and over-
flow at the top of the pipe L into the upper channel C of the battery trough A
and thus fresh liquid is supplied exactly as it is required and no faster while
the denser exhausted liquid accumulates in thebottom of the keg(which should
not be unnecessarily shaken) until the whole of the liquid is exhausted when
the keg must be emptied and replenished. If a Smee's battery is used with
this arrangement the liquid in the battery will not be preserved so fresh as it

page_text: is in the case of using batteries which evolve no gas in the zinc solution for
the gas agitates the liquid and mixes the exhausted portion of the liquid with
the fresh before it can run off by the channel below. In the case of such a
battery the level of (M) the top of the supply pipe L must be lowered until
it is found that fresh liquid runs from it before that in the battery is too much
exhausted. The vulcanized caoutchouc tubes will adhere firmly to the leaden
pipes when the ends of the elastic tubes are stretched over the ends of the pipes
the internal diameter of the elastic tube being rather less than the external
diameter of the pipe the extremity of which should also be swollen outwards.
A small tap (not shewn in the Drawing) should be fixed over some part of the
upper channel C and should communicate by a pipe either to a cistern of the
solution or simply to a supply of fresh water the tap being worked by the
well-known contrivance of a ball floating in some part of the channel so as to
let in a supply of liquid as the level of the solution in the battery falls below
its proper height which it does by reason of its contraction in bulk as the
battery works. When the battery is of such sort as to be perfluent from
cell to cell the tube E is to be. connected with the last cell or that which
would be the discharge cell, while the tube K is connected with the first or
supply cell. The other liquid of the battery (where another is used) which
becomes specifically lighter by use, is to be discharged and supplied by other
means, such as by the capillary syphons herein-before specified.
Fifth our Invention consists of what we call a negative supply apparatus
by gravitation which is used for supplying and withdrawing from batteries
such liquids as become specifically lighter by working the battery especially
that class of the said liquids which can be renovated by dissolving in them a
fresh supply of their solid material such as is the case with the solution of
sulphate of copper. A vertical section of the said apparatus is represented in
Figure 3. A shallow tray B. B. (of sheet copper or wood cemented with
marine glue being a material not affected by the solution) is fixed close to the
galvanic cell A. A. (the various elements of which are not shewn) the top of
the tray being level with the top of the cell. A syphon C. D (of the ordinary
sort) say of glass is arranged so that one end of it C shall be at the lowest
part of the interior of the tray and the other end D at the bottom of the
sulphate of copper in the cell while another syphoor E F is fixed by the side
of C. D. and arranged so that one end of it E shall be just below the surface
of the sulphate of copper solution in the cell while its other end F is just
below the solution in the tray (B B) the tops of both syphons being on a
level with one another. The ends of the syphons are turned upwards so as to
prevent air bubbles from entering and to prevent (in the case of the short

page_text: one) a fall on the level of the liquid from emptying it. There is a spout (not
shown) at the side of the tray at the highest level at which the liquid should
be kept, so that when the liquid rises (by increasing in bulk as the battery
works the liquid shall flow off thereby instead of overflowing the cell. A tray
or flat surface G. H of fine basketwork with a piece of fine netting stretched
over its upper side is supported in the solution tray B. B. slightly on a slant, so
that one side G shall be just below the surface of the solution, while the
opposite side is about an inch lower. On this tray are laid small crystals of
sulphate of copper in little heaps about an inch in height. Hence as the
solution becomes exhausted in the cell it rises to the surface and flows out by
the surface syphon (E F) into the tray permeates the heaps of crystals and
dissolves a portion of them thereby becoming dense and sinking down through
the tray or colander G. H when it re-enters the cell through the bottom
syphon C. D.
In some batteries in which the negative solution above men-
tioned is transmitted from cell to cell and becomes weaker in each successive
cell (the level of the solution in the last cell not being materially lower than
that in the first) this arrangement can be applied to thewhole series by placing
the bottom syphon C. D. in the first cell and the surface syphon E. F. in the
last, the tray B B extending from the one to the other. When the negative
solution is used in a porous cell (instead of in the outer cell) this arrangement
can nevertheless be applied. This improvement saves bulk in the battery,
and the solution of the crystals is more perfectlyperformed in the larger space
afforded by the tray (BB) than where the crystals are lodged in a nest within
the cells of the battery itself.
Sixth our Invention consists of a self-clearing capillary tube syphou a
vertical section of which is given in Figure 4. This syphon is intended for
the purpose of transferring liquids to or from the cells of a galvanic battery.
Ordinary syphons have frequently been used for such purposes but their action
is stopped whenever an air bubble enters them and they are considered
troublesome to refill in such cases and uncertain in their action. Ordinary
cappilary syphons composed of porous materials are for the most part acted on
by acids and they discharge liquid very slowly in comparison with their bulk.
Capillary tubes of glass obviate these difficulties, but if an air bubble enters
them it arrests their action by lodging at their discharge orifice, so that they
require attention whenever the flow of liquid intermits and allows air to enter.
This great defect is obviated by making the discharge end of the tube to be
of a conical or trumpet-mouthed shape gradually widening until the lower end
is or of an inch internal diameter as is shewn in section at S in the
Figure (4) S. y. p. representing the syphon consisting of a tube (glass being

page_text: by the liquids. It is to be observed, however, that many solutions are suitable
butnot anysolutions, those preferred beinghydrochlorate of ammonia or nitrate
of potash, next to the positive plate which is preferred to be of zinc, while the
negative plate and solution may be varied in many ways, but sulphate of
copper solution and copper plate according to the plan invented by Professor
Daniell, is preferred, or nitric acid and a surface of compact conducting carbon
is also very suitable for many purposes.
The solutions of salts are very
suitable if made about half or one third saturated and rather warm and with
from 1 to 3 part by measure of sulphuric acid (nitric or hydrochloric may
be used instead). We do not claim the use of solutions of salts simply as
such, in batteries being aware that they have been in use for a long time in
lieu of dilute acid in batteries using a single liquid between the two metallic
elements but we claim the use of the solutions of salts in lieu of dilute acid,
in double fluid batteries, that is, in batteries which use a different sort of solu-
tion next the other galvanic metal in the cell whatever that metal or solution
may be. The value of our improvement consists in the fact that a two-fluid
batterycharged with such a saline solution next the zink, is less proportionately
reduced in its power than a one-fluid battery so charged as compared with each
kind of battery when charged with dilute acid in the usual manner. A fact
which has not hitherto been publicly known or at least turned to any practical
account. And hence saline solutions having been laid aside as too feeble for all
purposeswhere much electric power was required, becausetheir feebleness was
found to be such when theywere tried in single fluid batteries. The advantages
of being able thus to use saline solutions is that the zinc plates do not require
the constant cleaning and amalgamating which is so generally found necessary
to prevent local action when dilute acid is used.
Eighthly our Invention consists of an improved concentric cell as repre-
sented in Figure 5 of the. Drawings annexed. The elements preferred to be
used for this cell are carbon with nitric acid for the negative part and zinc
with the salt solution herein-before described for the positive part but the
elements may be considerably varied. The negative element o. o. may be
made from some of the known carbonaceous compositions pressed up in a
mould, and raised to a full white heat for some time to impart its full electric
conducting power in the manner that has frequently been practised or it may
be cut out of a solid piece of conducting carbon such as is found lining gas
retorts that have been long used. It is in the form of a straight rod of a
polygonal section (octagonal being preferred) and is placed within a circular,
porous cell P. P. (of biscuit ware) which fits it as closely as conveniently may
be. The carbon projects a short distance beyond the top of the porous cell

page_text: and from its upper end to a short distance below the surface of the liquid
which surrounds it in the porous cell it is made of a rather smaller section
than the lower part of it, and one side O' of this smaller part is cut away to a
certain extent (as shewn in the Drawings) so that there is room enough
between the side of the carbon at that part and the porous cell to insert the
end of a capillary or other syphon or a tube to draw off the liquid (nitric acid)
as it becomes exhausted. Down the centre of the carbon there is a hole
QQ which becomes larger conically at the top Q' to receive a tube or the
liquid supplied from any convenient source. The hole Q passes through the
lower end across which there are grooves R R radiating from the central
hole to each of the sides of the polygonal form. By these means the liquid
has free circulation from the central hole at which it enters to every part of
the external surface of the carbonacious element and can pass freely upwards
between the polygonal sides and the curved sides of the porous cell as in so
many clear channels. If the carbon were circular in section and nearly fitted
the porous cell then when it stood against one side of the cell there would not
be the above-described free passage for the liquid at that side. Now it has
generally been found difficult in energetic batteries which contain carbon as
an element to attach a conductor to the carbon so as fully to carry off the
electric power because contact at one or two points which is sufficient in the
case of metals is not sufficient here by reason of the comparatively feeble
conducting power of carbon and its somewhat friable and weak mechanical
structure prevents the application of much pressure at the points of contact (as
is done by a set screw in the case of metallic connections. This difliculty is
overcome by obtaining an extensive surface of contact with a metal as copper
when the electricity will pass freely from any point of the copper to any
conductor that is in moderately tight contact with it. Now covering the top
of the carbon with copper by the electrotype process has been practised but it
is a troublesome process and if the contact is disturbed by mechanical violence
or by the expansion of the copper coating by heat or by chemical action
beneath the contact cannot be properly renewed without electrotyping the
carbon afresh. We therefore make contact by means of a strap of copper
S. S. S. passed round the top of the carbon and bound tight by means of a
screw T. T. The other end S' of the copper strap can be connected in any
of the usual ways to the next conductor in the circuit. Around the porous
cell is a cylinder of sheet zinc Z. Z. fitting the porous cell as closely as
convenient and a pot A A (preferred to be of stone ware) receives the
whole of these elements. The zine cylinder should terminate a short way
below the surface of the liquid in the pot A. The solution next the zinc may

page_text: (
be supplied and drawn off by the arrangement herein described as the
gravitation supply" apparatus and the liquid next the carbon may be
supplied and drawn off by means of the "self-clearing capillary tube syphons"
herein-after described but we do not confine ourselves to any particular modes
of supplying and drawing off the liquids. An important feature. of this cell
is the close approximation of the positive and negative elements whereby
greater power is obtained. The cell is made very compact it holds very
little liquid and therefore may be quickly charged by the same means that are
used to keep up the supply while working and when required to act for
only a short period as for blasting rocks or trying short experiments a very
little of the liquid is required to make it work. The reduced diameter of the
carbon at and above the surface of the liquid in the porous cell prevents
the liquid from rising to the top of the cell by capillary attraction between the
surface of the carbon and the cell and prevents any accidental motion of
the carbon from splashing the liquid over the edge of the cell. The same
advantages are secured in the case of the zinc by making it terminate beneath
the surface of the liquid. A strapof zinc mayrise fromthe zine over the edge of
the pot to conduct the electric current in circuit as usual and the lower end
of the zinc cylinder should be irregular or undulated in order to allow the
exhausted liquid to pass freely and this result is better secured by having
grooves in the bottom of the pot (A leading to the discharge hole (not
shewn in the Drawings.
Ninthly our Invention consists of the following improved arrangements for
a series of cells. A number of the "improved concentric cells" last before
described are fixed in rows in a strong trough of wood. Between the rows is
fixed a channel or small trough of stone ware a transverse vertical section of
which is shewn at A in Figure 4 the bottom of the channel being about on
a level with the top of the carbons in the cells. This channel is kept filled to
a proper extent with a suitable solution or liquid such as nitric acid by means
which will presently be described and the "self-clearing capillary tube
syphons" already described are hung each with one end in the channel and
the other in the hole in the top of the carbon of every cell, so as to keep a
supply to each carbon-the rate of flow of the tubes having been first pro-
perly regulated. At the middle of the said supply channel or connected with
it by a syphon there is a square basin about three inches diameter with
vertical parallel sides and in this there is a float of glass of a flat shape at
top and bottom and of-a diameter just sufficient to go freely into the basin.
Over the centre of this float hangs the lower orifice of a large glass syphon
the orifice being about a quarter of an inch diameter or less and horizontal

page_text: and smooth so that when the float rises up to it it will close the orifice so
well that there shall be but a slight flow from it if any. The height of the
orifice of this syphon above the float must be so adjusted that the float shall
check its flow as soon as the liquid has risen to within a safe distance from the
edge of the supply channel say half an inch, a height from which the
capillary syphons can easily raise the liquid. Now this said syphon whose
outlet end hangs over the float has its other end in a carboy containing the
stock of liquid and there is a glass stop-cock near its discharge end to turn
off the flow when the battery is not in action. There is also a little glass
pump or a suction apparatus at the highest part of the syphon to exhaust its
air from it and set it in action the stop-cock being in such cases turned shut.
Now between the aforesaid rows of cells and just beneath the supply
channel there is a discharge channel of similar construction which is fixed a
few inches below the level of the tops of the cells and the self-clearing
capillary syphons are set from each porous cell to discharge into this channel
which is on a slight slant to one end where it projects through the end of the
wooden trough or case and terminates in a spout. The discharging capillary
syphons should be made to discharge the liquid faster than the other syphons
supply it and should have their ends terminating about one third of an inch
below the top of the porous cell so as not to reduce the liquid below that level.
The supply syphons should supply the liquid about three times as fast as it
would be actually exhausted by the ordinary working of the battery so that if
any syphons should supply it more slowly the supply will still be sufficient
and if on the other hand any should supply it more quickly the excess will
not be wasted because instead of letting the liquid run off to waste as ex-
hausted it is collected and used a second and third time the waste of the
supposed accidental excess of supply from any syphon being thus incurred
only once in three times and then only in the case of liquid which has been
two thirds exhausted already.
When a water lute covers the battery case the discharge channel can be
secured likewise by a hydraulic trap which may be made in various ways one
good method being such as is shewn in Figure 6 which is a longitudinal vertical
section (of the battery case) through the discharge channel. A A. represent
the end of the case. B. B the discharge trough. Ca recess or hollow in the
bottom of the trough which forms a little receptacle there for liquid. D is a
division or diaphragm extending from side to side of the trough and nearly
but not quite to the bottom of the recess at-C and reaching up to the top of
the sides of the trough where it meets the end of the case A and the
junction is made close with cement such as marine glue or hees'-wax melted

page_text: up with about as much fine sand or powdered flint as it will bind together
which will be found to resist to a considerable extent the action of nitric acid.
The supply of acid may be conveyed to the upper channel by means of a
similar trap and the supply and discharge of liquid to the zinc may be effected
by the gravitation supply apparatus before described.
Tenthly Our Invention consists of certain improvements in the treatment
of iridium and the manufacture of articles in iridium for the purposes of our
said Invention. The metal iridium is valuable as a material for some purposes
from its extreme infusibility and also for its hardness and non-liability to
oxidation or other chemical injuries but owing to its infusibility it is very
difficult to work it into solid masses of suitable form and compact texture.
Subjecting it to the heat of the disruptive discharge of a powerful galvanic.
battery is already known to be one of the best means or the very best mode
of fusing it) but carbon (such as coke) is the only known substance which
will conduct the said galvanic power and upon which the disruptive discharge
can be made without fusing. Hence this galvanic power has been applied
between two pieces of carbon to fuse iridium. Now it is found that the
iridium becomes injured by contact with carbon or carbonic gases at high
temperatures for it becomes thereby porous and of a loose texture. Some
devices have been employed to support the mass of the iridium as much as
may be out of contact with the carbon as for instance by phosphate of lime
on account of its reputed infusibility but this is inconvenient inasmuch as
even that material fuses and is moreover a non-conductor of electricity.
Now our improvements in respect of the above process are as follows:
We form a bed or cup or mound on which to fuse the iridium from the
powder or grains of the iridium itself the said bed or cup or mound of iridium
powder being supported on a suitable solid conductor of electricity and heat
such as a slab or trough of copper. The bed of iridium powder is made of
such thickness to prevent the heat from penetrating downwards through it so
intensely as to cause adhesion or combination between the iridium and the
copper. It is preferrable that the bed of iridium powder should be not less
than half an inch in thickness and that the mass of copper should also be
about half an inch or more in thickness so as not readily to become heated.
The positive wire from the battery is to be first connected with the said mass
of copper: We then use a solid piece of iridium itself as the opposite electrode
with which the negative wire of the said galvanic battery is to be connected
(this is the wire from the zinc pole when an ordinary sort of battery is used).
This solid iridium electrode should be not less than two inches long cylindrical
in form and about one fifth of an inch thick and terminate in a blunt point.

page_text: Its material should be as pure as can be conveniently obtained but it will not
materially injure the resulting process (the fusion of the metal beneath it in a
pure and solid form) if it be formed of iridium that has been somewhat con-
taminated with carbon. This electrode of solid iridium may be conveniently
fixed up by its further end in a holder or clamp of brass or iron to which the
said negative wire and a wooden handle is attached. It is preferable to employ
a battery of a series of cells sufficientlyextensive to give an electromotive force
equal to that of a series of seventy cells of Professor Daniell's battery or
more and the quantity of the electric current should be such that when the
circuit is completed by close contact of the wires the amount of zinc consumed
in each member of the galvanic series should be not less than eight grains per
minute but three or five times that power is desirable if a solid ingot of iridium
is to be made of the thickness of one fourth of an inch. The person operating
should have the eyes protected by spectacles of verydark neutral colored glass
and the face protected by a thick white wrapper.
The process is then conducted as follows-To form an ingot the solid
iridium electrode is held by its handle nearly vertical with its point downwards
over the bed of iridium powder it is then gently brought into contact with
the top of the powder and immediately withdrawn about one eighth of an inch
from it upwards and then moved slowlyhorizontallybackwards and forwards in
a line along the top of the bed of iridium while the disruptive discharge of
electricity plays between the powder and the upper electrode. When the
fusion has taken place over a sufficiently long and broad line on the surface of
the powder the upper electrode is withdrawn and the fused mass left to cool.
It is then when cool raised from the bed of powder the loose grains scraped off
and the bed again neatly made up rather longer and broader than the ingot
that has been formed and the ingot replaced upon it but with its lower side
upwards after which the fusion of this side of the ingot is completed by a
repetition of the manipulation before described. To form a slab or sheet of
iridium the upper electrode should be moved about over a flat surface of the
powder without allowing the discharge to play too long on any one part. The
half fused slab or network thus produced is then to be turned and fused on the
other side as described in the formation of an ingot. After a piece of solid
iridium has been formed it may be worked into better shape by holding it by
one end or side in a hand vice the positive wire being in connection with the
vice and thenthe upper electrode used as before to cause thegalvanic discharge
to play on the parts which are to be reduced or levelled. And to fill up cavities
on its surface the discharge should be made to play first for a moment in the
cavity and then close around it so that the circular melted spot which always

page_text: exists under the discharge shall have its circumference kept just bordering on
the centre of the said cavity. The pieces of iridium so formed may be worked
into further shape by the same means that are adapted for precious stones and
several other hard substances.
Eleventhly our Invention consists of an improved self-acting rheostat which
we call "the equalizer." Figure 7 is a front view of the interior of this appa-
ratus. Figure 8 is a vertical section on the line 1. 1. and Figure 9 is a
vertical section on the line 2. 2. This instrument consists of a wheel (A. A)
of non-conducting matter with the greater part of its circumference bound
round with platinum wire, the turns of wire being separate from each other by
a short distance to avoid contact between them one end of this wire is in
metallic connection with the spindle of the wheel while the other end termi-
nates on the circumference. The wheel revolves on a horizontal spindle in a
non-conducting vessel (of glass for instance) in which there is sufficient mer-
cury M to cover an arc of about 45° of the outer edge of the wheel. The
vessel is then filled up with water to prevent oxydation at the surface of the
mercury and to prevent the platinum wire becoming too hotwhen the current
passes. The spindle passes through a waterproof bearing through the glass
vessel and a metal spring S pressing on its extremity is in metallic connection
with one end of the wire of the regulator coil R, R, the other end of the
said wire being in connection with the binding screw Z. The regulator coil
consists of a coil of insulated copper wire (of about one seventh of an inch
diameter generally)wound in a sort of bobin uu and having an iron cylinder V.
moving freely vertically through its centre its medium position (being about
that which is represented in the Drawings) being that position in which it is
driven upwards with the maximum force by the action of the electric current
when the coil wire is included in the circuit. The iron cylinder V may be
weighted at its lower part with the moveable weights W (a view of one of
which from above is given separately in Figure 10) and is suspended by the
non-magnetic stem X with a cord or chain from the barrel F to the other side
of which a counterpoise K is similarly suspended (by cords I and J) which
should not be less than will suffice to overcome the resistance to motion of the
wheel A and not so large as to counterpoise the weight of V. In this coun-
terpoise there may be a vertical hole through which a fixed pin L can pass to
keep the counterpoise from swinging about. From the mercury M the con-
ducting connection is continued by a slip of copper P tipped with platinum
where it touches the mercury. The copper part of it being well yarnished the
other end of this slip is connected with a binding screw Y. The whole appa-
ratus is fixed in a suitable framework of wood as is shewn in the Drawings

page_text: and it is included in a galvanic circuit by means of the binding screws Y and Z
and the weights W. W. W. laid on until the requisite amount of current is
found to pass. The battery or source of the electric current should be of such
quantitative power that when the current is doing its intended work about half
of the platinum coil around A (the other half next to B) should be out of the
mercury. The current will then be kept nearly constant even though the
resistance of the work to be done or the power of the battery may afterwards
vary to a considerable extent because the iron centre V rises or falls according
as the current increases or diminishes in quantity and this rise or fall draws
out or sinks down more or less of the platinum wire into or from the mercury
and thus increases or diminishes its resistance in the circuit thereby counter-
acting the increase or diminution of the current which variation causes the
motion of V. A modification of the "equalizer" which will be found useful
when the electric current to be equalized is not of great intensity (or from
great electromotive power) is represented in Figure 11. A square or other
shaped framework (A) as slender as may be and of non-conducting material
(as porcelain) is fixed to the lower end of the iron centre V of a regulator
coil (R) such as.that before described) and is wound round horizontally with
a spiral or zig-zag of platinum wire thewire being of thicker substance towards
its upper end which is connected with V its lower end is fixed to the lower
part of A. This rises or falls in a cup or vessel G which is so far filled with
mercury (M) that when the regulator centre V is in its position of maximum
force (or rather a little below that) then the frame (A) is half immersed in
the mercury the rest of the vessel (G) is filled up with water. The part of V
which enters the water should be well varnished. Weights W. W. W. can be
placed on the spike at the top of V to regulate the amount of the current
which should pass as has been described in the previous machine. Now when
the machine is included in the circuit by Y and Z the current from Y passes
through P to M thence through that portion of the platinum wire that is not
immersed in the mercury to V and up X (which should be of metal) and
through the bit of thick platinum wire S' which dips vertically into the cup q
which contains mercury and which is fixed to U by the platinum spike T
which also serves to conduct the current onwards to the end of the regulator
coil R which is soldered to the case or bobbin U. The other end n of the
coil conducts the current on to the connection Z. The action of this machine
is similar to the one previously described. Where it is undesirable to use
mercury an arrangement may be made for making a solid conducting commu-
nication in place of the fluid. This may be done in tlie manner represented
in Figure 12 in the second-described arrangement for the self-acting rheostat

page_text: where the platinum wire is fixed to the lower end of the moveable part of the
regulator the fine platinum wire is to be wound in a close spiral around a
cylinder of porcelain A' (which is a non-conducting material and not affected
by wet) instead of the piece A. A which cylinder is attached as a prolongation
to the end of the moveable part of the regulator and has a slight groove
spirálly around it to receive half the diameter of the platinum wire. A number
of springs of hard platinum wire m³ m' m' extend upwards from various
points in a little horizontal circle (in a holder of varnished brass) fixed imme-
diately beneath the said cylinder wound with-platinum wire so that some of
the springs embrace everyside of the cylinder so as to touchdifferent individual
spirals of the helix of platinum wire according as the cylinder is raised or
lowered by the regulator. The tips of the springs are turned outwards from
the cylinder to prevent their catching against the under sides of the platinum
helix wire. The circle or brass holder from which the springs arise is placed
sufficiently low to allow of the moveable part of the regulator descending to its
furthest suitable extent without bringing the cylinder into contactwith the said
spring holder. There may be about thirty small springs of platinum wire rising
from the circle of the spring holder. A similar arrangement can be adapted
mutatis mutandis to the first-described species of equalizer.
Twelfthly our Invention consists of a compensating dial balance galvano-
meter of which a vertical section is given in Figure 13 and Figure 14 with
the side of the framework removed. This galvanometer possesses several
advantages for the practical galvanist especially where a constant indicator is
wanted to connect in the circuit of a battery so as to shew the rate at which
the electric current is passing and the consumption going on in the battery
during the performance of any work without obliging the observer to do more
than glance at the dial of the instrument as at a comnion clock. It consists
of a hollow coil R R or insulated copper wire wound around a bobbin or reel
of sheet brass U. U. U &c. This coil is fixed in a suitable wooden frame-
work AAA &c. with the axis of the 'coil vertical. A hollow cylinder of
brass forms the centre of the coil and in this slides a rod of pure soft iron V,
preferred to be hollow. (Its length breadth &c. is shewn properly in the
Drawings in which it is represented in its lowest position in the coil.) To the
top of this iron centre V. is fixed a brass rack A which works in a brass
pinion B. which is set tight on a spindle c. which turns' freely on a small
bearing-part in a framework of brass & & &c. which is fixed to the top to the
coil R: On the same spindle a pulley (preferred of brass or wood) D. D. is
set tight over which passes a string sustaining a weight W so as to partially
counterpoise the iron centre V which hangs by the rack A on the pinion B.

page_text: The spindle c passes through to the front of its bearing-frame &. 8. and carries
an index hand E the point of which traverses around a circular scale or dial-
face. Now to the side of the pulley D, is fixed a weight (of lead) G at such a
part of its circumference that when the rack falls so as to draw the pinion and
pulleyround to its furthest degree the centre of gravity of theweight is brought
round rather beyond the lowest point so that as the rack rises the weight G
falls first to its lowest point and then rises on the other side of the circle and
the pinion is of such diameter that when the rack (or rather the iron centre V)
is raised to the highest point to which the electric current passing through
the wire of the coil will conveniently act to drive it up then the spindle
weight G shall have its centre of gravity carried rather beyond the highest
point of its circle (bythe term "rather beyond''in this description we mean that
the angle of 30° beyond is considered preferable. The ends of the wire
of the coil R, R, are severally connected with two screw clamps (Y and
a similar one hid by Y in the side view) whereby the instrument can be
included in the galvanic circuit. The wire of the coil should be very thick
when the instrument is intended tomeasure thequantitativepower of an electric
current. The spindle weight may be made so large that when it is brought
into the position which it occupies when the iron centre V is at its lowest
place this spindle weight itself (with the assistance of the pulley weight W)
just counterpoises the weight of the iron centre and rack V and A. And the
index E is so placed that (in that position of the spindle it points to the
highest point of the dial the beginning of the scale and almost touches a
pin F which projecting from the scale prevents the index E from turning
backwards further than the commencement of the scale.
The pulley
weight W should not be lighter than will rather overbalance the spindle
weight G when it stands at its furthest horizontal distance from the perpen-
dicular centre line. The effect of this overbalancing is that there will not at
any point of the revolution of the index be an error arising from the back lash
of the rack and pinion. The pulley weight may be so far additionallyweighted
towards counterpoising the iron centre (V) and the spindle weight G may also
be so varied (consistentlywith preserving as before-mentioned in relation toW)
as shall be found to conduce most completely towards making the index mark
equal spaces around all points of its scale, when equal increments (or additions)
are caused in the electric current, this result being the object of the spindle
weight G. The rack pinion and spindle should be constructed to work with
as little friction as may be. There is a little set screw H which works in the
brass framework (88) against the back of the rack (A) to adjust the depth of
the locking of the teeth of the rack and pinion. The rack works through a

page_text: hole (above the pinion) in the brass framework which confines it sideways, but
not back and front ways (these terms sideways &c. here used refer to the rack
and not to the whole instrument. To graduate the scale on the dial-plate
another galvanometer already graduated should be used connected in the
same circuit and the current is then. varied by means of a rheostat included
in the circuit the unit of measure being that amount or rate of electric
eurrent which is produced by the electromotive oxydation of one grain of zinc
per minute in a galvanic cell included in the circuit. The iron centre should
be of the purest soft iron well annealed after it is completed and polished so
that it may undergo no hardening of its surface even by the process of
polishing. After it is finally settled it may be annealed by packing it closewith
fine and pure lime pressed around it, in an iron box, and raised to a white heat
for such time that the heat shall have penetrated thoroughly through the
lime after which it is allowed to cool gradually. This instrument may be
modified so as to form an intensity galvanometer, that is, to indicate the
electromotive force which causes the current and the consequent power of the
current to overcome resistances, apart from the effect of quantity, or the size
of the battery plates or the amount of resistance actually in the circuit. This
species of galvanometer will be found very useful to test the said quality of the
current after the other form of galvanometer has shewn the quantity of the
current. This "intensity galvanometer" is formed just like the preceding one
but in place of the thick wire in the bobbin or case (U, U, U,) we wind a very
long and thin insulated wire not more than 1th of an inch thick and not less
than one or two hundred feet of it (the more the better) and there is a brass
screw termedtriode screw, which passes throughametallic screwhole in metallic
connection with one of the before-mentioned screw clamps Y the said triode
screws passing in such a direction thatwhen screwedup it presses its endtightly
against a piece of metal (brass) connected metallically with the other screw
clamp, so that the electric current in that case can make a short and free
passage from one screw clamp to the other without being resisted by passing
through the long thin wire. With this appendage the galvanometer can be
kept (like the other) always included in the electric circuit without materially
obstructing it (the triode screw being screwed tight) and the intensity of
the current can be seen at any time by loosening the triode screw for a
moment..
Thirteenthly our Invention consists of a differential galvanometer of the
following improved construction. The object of this instrument is to show
separately both the quantity and intensity of the electric current without
having two separate instruments for those purposes and without the necessity

page_text: of greatlyintermitting the currentwhile its intensity is being examined. There
seems good reason for believing that sometimes the intensity of the current
changes by the very act of obstructing it with the wire of the intensity galva
nometer. Hence another probable advantage in the arrangement for deter-
mining the intensity without obstructing the current which we have next to
describe.
The framework or box containing a quantity galvanometer (that is one
which does not materially obstruct the current while it measures it) such as
the dial-face galvanometer already described is prolonged in one direction so
as to leave a long empty space within the box. Into this space are arranged
a series of coils of insulated wire copper being preferred of various lengths
and diameters so that each coil in succession shall oppose about three or five
times the resistance to the current, that the coil next preceding it does. One
end of the galvanometer wire itself is connected with a screw clamp to receive
one of the wires of the circuit. The other end of the galvanometer wire is
connected with a slip or flat rod of brass which passes along the side of box
being inlaid in its side and having set screws screwed through it at intervals
along it. These set screws have milled heads projecting at the outside of the
box and when screwed in, their ends abut severally against pieces of brass fixed
firmly inside the box and each connected with one end of one of the coils but
one say the last of these pieces of brass and all the opposite ends of the coils
are collectively connected with a screw clamp which receives the other wire of
the circuit. Hence when all the set screws are loose and the two wires of the
circuit are fixed in the two screw clamps then by screwing up the set screw
which sets against the last of the before-mentioned interior pieces of brass
the current passes through the galvanometer coil alone whereby the quantity
of the current is indicated then by loosening that set screw and tightening
one of the others the current will pass through the coil which is thereby con-
nected with that set screw and will be somewhat reduced in quantity by the
resistance of the coil. Of the various set screws that one should be tightened
in this way which will reduce the quantity of the current by an amount which
the galvanometer will measure with sufficient accuracy but not more than
about one half of the current one tenth is often a suflicient reduction. Now
the degree to which the resistance of a particular coil thus thrown into the
circuit reduces the current from a given quantity is an inverse measure of the
intensity of the current. Numbers should be attached to the set screws of
the several coils indicating their relative resistances to the circuit and the
actual degrees of intensity of various currents experimented upon in this
manner may be more definitely determined (beyond a mere comparative result

page_text: between two existing currents) by reference to a set of tables which may be
drawn up for the purpose on principles already known or better by the appli-
cation of a simple mathematical formula. The form of these coils is preferred
to be as follows. First. They may be wound on a circular bobbin but with
alternate layers of wire in reversed directions. Or Second the wire may be
doubled in half and its two ends brought together so as to form a double wire
this being wound up into a coil with the two ends projecting to connect in the
usual manner the circuit of the current. Or Third they may be wound on a
flat centre piece so as to form a coil as if it has been crushed flat sideways
the object being to make the current in different parts of the wire of the coil
to act with equal and opposite forces on anything external to the coil so as to
destroy any electro-magnetic power of the coils lest they should affect the
galvanometer's indications or other neighbouring instruments.
Fourteenthly our Invention consists in the employment of a chain and
barrel in place of a rack and pinion for supporting and imparting motion to
the electrode shaft in certain electric lamps. This improvement has special
relation to those electric lamps in which a rod which we term the electrode
shaft is used to push one of the electrodes towards the other the electrode
being either fixed in a socket at the upper extremity of the shaft as a continu-
ation thereof or the shaft being used to push the electrode through a tube.
In place of the rack on the shaft and the pinion into which it works we use
a chain (preferred of brass) attached to the lower end of the shaft and
passing over a barrel on the spindle where the pinion would otherwise be.
Moreover the shaft is to be hollow with a slot throughout the greater portion
of its length and the connecting chain passes from where it is fixed at the
lower end of the shaft up to the hollow of it and passes out (to come round
the barrel) through the slot the other end of the connecting chain being
fastened to the barrel and on another part of the same barrel the counter-
poise weight and compensation chain may be wound. The counterpoise.
weight may slide in a tube to guide it and prevent it from oscillating and a
compensation chain hangs from the counterpoise weight and is so long that
its lower end shall always rest on the bottom of the lamp case or of the tube
in which the weight moves and the weight of this chain should be inch for
inch equal to the electrodes the connecting chain and the chain or cord which
suspends the counterpoise weight all taken together in equal lengths. This
counterpoise chain tends to preserve the balance of the shaft at all periods
during its ascent as the electrodes wear away. The advantages of this mode
of connecting the shaft by a chain are First that in some cases it reduces the
height of the lamp as any part of the shaft may rise into the part of the lamp

page_text: where the light burns, as it is not so necessary to preserve it from dust or rust
as it is when the teeth of a crank are cut upon it; hence there is no need of
such an extra length of shaft above the part which occasionally comes down
to the spindle Second it is easier to construct and does not require such
nicety of position relative to the spindle and Third the friction of this mode
of supporting the shaft is less than it is when the weight rests on the teeth of
an ordinary rack and pinion.
Fifteenthly our Invention consists of an improved electric lamp movement
which has relation more particularly to such electric lamps as have one of
the carbon electrodes pushed up towards the other as one wears away the
shaft AA (Figure 15) which this movement actuates may either carry the
electrode in a socket at its end or may merely act as a rod to push the elec-
trode through a tube in a manner that is well known. This shaft consists of
a screw, on it is screwed a crown tooth wheel B B with the teeth down-
wards. The toothed or click wheel (B B) rests on a bit of upright circular
tube (C. C) through which the shaft passes and thus the shaft being screwed
into the centre of the click wheel (B) is itself, upheld. The upright fixed
tube (D D) over the top of which the tube (C) fits is furnished with a key
fixed inwards which fits into a slot E which extends down the whole length
of the screw shaft. Hence when the wheel is turned round the shaft cannot
turn with it by reason of its slot and key and therefore the shaft is caused
to move up or down. Now a double click f f works into the teeth of the
wheel the click being fixed on a central pin g in a horizontal sliding rod h
which is close beneath one side of the wheel and slides endways through
rectangular holes in the brass framework AA and is provided at one end
with a perpendicular slot hole i in which a small crank of a spindle (not
shewn) works being made to revolve by means of a mechanical force such
as common clockwork whereby a réciprocating motion is given to the click
rod (h). Again the click being heavier at one end than at the other f
the light end tilts up against the teeth of the wheel (B) and as the click rod
moves reciprocatingly the click catches the teeth and works the wheel round
in one direction whereby the shaft A is moved upwards as before explained.
Therefore to reverse these motions the other end of the click must be kept
pressed gently in contact with the teeth of the wheel. This is effected by
the top of the rod (X) pressing upwards from beneath against the heavy end
of the click. This rod (X) is fixed vertically in the top of the iron centre (V)
of a regulator coil (R) such as we have already described as applied to regulate
the self-acting rheostat the wire of the coil is included in the circuit of the
electric current which passes through the carbon electrodes to produce the

page_text: light so that when the current acts too powerfully it lifts the iron centre of
the regulator and thereby elevates the heavy end of the click which working
on the wheel makes the shaft and electrode to descend. Now the force of the
ascent of the iron (V) might (when the current is suddenly established) press
the click too tight against the teeth of the wheel to prevent this the top of
the rod X is made hollow and the lower part of the hollow is filled by a spiral
spring K upon which rests a small rod L. in the bore of the rod X and
projects beyond the top of it (X). The small rod L is kept pressed down
upon the spring by a cross pin M fixed through it and passing through a
short slot in each opposite side of the hollow rod (X) so that the small rod I.
can he pushed down for a short distance against the elasticity of the spring(K).
It is with this spring force that the regulator presses the heavy end of the
click upwards the small rod I has a horizontal cross head along which the
end of the click can slide as it moves horizontally. The rod X is so long that
when the light end of the ratchet is jambed in a tooth of the wheel so that
the other end hangs down the rod X in rising touches the cross head of L
and so
brings the immediate power of the regulator to bear on the click to
disengage it, but the rod X is prevented (by a cross pin in the iron centre
below the bottom of the coil) from rising so high as to follow the end of the
click higher than its medium or horizontal position the lighter force of the
rod L raised by the spring is the force used to bring that end (f) of the click
into actual contact with the teeth of the wheel. Now if the clockwork which
works the click rod be powerful the rising of the shaft (A) will drive the
electrodes together too forcibly. This is prevented by making the tube C
on which the wheel rests to be supported not rigidly but by a spiral spring
(nn) which winds loosely around the fixed tubes d and the force of which
can be regulated by elevating or lowering the ring o to which the bottom of
the spring is attached by turning the nut p on which it rests, so that when
too great a pressure comes on the support C by the electrodes being pressed
together the support C sinks down and lowers the wheel slightly whereupon
its teeth in moving round catch against a projection (9) upwards from the
brass framework and thus the wheel is prevented from turning further in that
direction and the resistance thus opposed to the click stops the clockwork
motion. The supporting tube C under the wheel is prevented from lifting
the wheel too high above the click by reason of the framework A which fits
over a collar or shoulder on C. This framework AA is screwed firmly to
the (square) top plate of the regulator coil which is fixed in the framework of
the lamp. By this improved method a balance weight for the electrode shaft
is not required and the electrodes cannot be damaged by the surplus power

page_text: of the clockwork. A small rod (s) may project from the stem. (a) of the
iron centre so as to stop the fly or balance of the clockwork power whenever
the iron centre is in a medium position but to release the fly whenever the
iron centre rises or falls. The iron centre may have its weight partly coun-
teracted by being suspended from one end of a lever along which the other
weights can be shifted so as to regulate the balance of weight on the iron
centre as required.
Sixteenth our Invention consists in the substitution of acuminated plates
for the plain plates of metal now used in the "Daniell's constant" and some
other forms of battery that is, plates punctured all over their acting surfaces
with little holes and burrs around them as is done in tin plate for the manu-
facture of bread graters or nutmeg graters the burrs of the holes pointing
inwards towards the opposite element of the battery cell.
:
Seventeenth our Invention consists in the use of wire gauze in place of
the plain plates of similar composition used in the cells of galvanic batteries.
Several sheets of the wire gauze can be used placed flatways close to one
another.
Eighteenth our Invention consists in various contrivances for the prevention
of the spark resulting from the breaking of contact in galvanic circuits. In
most means which have been devised for obtaining mechanical power from
electric currents whether as a prime moving power or as a mover of light
mechanism for secondary objects where the primary use of the current is
for any other purpose
it is requisite to cause the current to pass intermittently
through certain wires or conductors and at every time the wire intermits a
spark is generally produced at the place where the conducting contact is inter-
fered with. Now this spark wears away and oxydizes the surfaces and thus
soon prevents good contact.
The following plans may be adopted for diminishing or preventing the spark
in, such cases. First the two parts of the circuit where the contact has to be
interrupted may be connected by a short piece of thin platinum wire so as to
allow a small portion of the current still to pass after the continuity of the
main conductor is interrupted. It is preferable to have the platinum wire just
so long as not to allow so much of the current to pass as will too much
frustrate the object for which the contact was interrupted and just so thick as
will prevent its being overheated by the electricity at the moment of breaking
the continuity of the main conductor. Or Second a series of conductors
may be used (such as elastic slips of metal) placed side by side for instance
to form the contact at that part of the circuit where it may have to be broken
at intervals so that their contact shall be broken quickly in succession but

page_text: not all at once, each of the conductors being so much thinner and longer
than the one whose contact was last previously broken that it shall arrest
about half of the current that was passing before the previous conductor of
the series was put out of contact.
And having now described the nature of the said Invention and in what
manner the same is to be performed We declare that the improvements
which we claim as comprehended in the said Invention are as follows-
First We claim the hydro-barometers herein-before described and the
employment of them in the cells of the galvanic apparatus so that the fresh
liquid supplied has to pass through them whereby the relative degree of
exhaustion of the liquid in the cells is indicated to the eye at any moment
by the difference of level between the liquids interior and exterior to the tube.
Second We claim the enclosing porous materials such as may be used for
ordinary capillary syphons for the liquids of galvanic batteries in flexible
waterproof tubes (vulcanized caoutchouc being the material preferred) as
before described and the use of a clamp or plug to act on the sides or orifice
of the waterproof envelope of the syphon so as to regulate the discharge of
the liquid as may be desired.
Third We claim the process of covering articles used for galvanic batteries
or in connection with them with a coating of sulphur as before described.
Fourth We claim the improved gravitation supply apparatus before
described that is to say, the use of a closed reservoir placed below the
battery connected with the cells of the battery by tubes in such manner that
the exhausted liquid which becomes dense by being used shall flow down one
tube and rest in the lower part of the reservoir or cask or while the
hydraulic pressure of this denser liquid in the said tube shall drive a supply
of the fresh liquid from the reservoir up the other tube into the cells.
"
Fifth We claim the "negative supply apparatus by gravitation before
described that is to say the use of a tray or shallow reservoir to hold a
supply of such liquid or solution as becomes specifically lighter by being used
in the battery in combination with syphons connecting it with the battery
one syphon leading from the lower part of the liquid in the tray to the lower
part of the similar liquid in the galvanic cell, while the other syphon leads
from near the surface of the liquid in the cell to near the surface of the liquid
in the tray. And also the use of a colander or porous support in the said
tray to hold matters to be dissolved in the liquid that is used when the liquid
is of such sort as to render that desirable. And also the application of
sulphur to the interior of galvanic batteries to render the joinings water-tight
and acid proof.

page_text: Sixth We claim the self-clearing capillary tube syphon before described
that is to say, the use of syphons composed of capillary tubes which have a
conical or trumpet mouth at their lower ends where the liquid is discharged
whereby they clear themselves of any air bubbles that may enter the tube.
Seventh We claim the use in double fluid galvanic batteries (in lieu of a
dilute acid) of a saline solution next the positive plate of a galvanic cell in
combination with a different solution next the negative plate of the same cell
with a porous diaphragm between them as before explained.
Eighth We claim in regard to the improved concentric cell before described
first the employment of a hole or bore from the top part of the negative
element to its lower part and channels cut in the said element horizontally
from the aperture of the said bore at its lower end to different parts of the
sides of the element. Second the use of the negative element of a polygonal
section or grooved vertically so that while it fits as close as may be to the
sides of the porous cell there shall remain vertical passages between the two
surfaces for the liquid to pass upwards at every part of the horizontal section
of the negative surface. Third, the reduction of the horizontal section of the
negative element from a little below the surface of the liquid in the cell
upwards so as to leave a freer space for the subsidence of bubbles and to
prevent the motion of the negative element from splashing the liquid over.
And Fourth the use of a band or strip of metal (copper being preferred)
drawn tight around the top part of the negative element by means of a screw
so as to obtain firm contact at many points between the negative element and
the strap for the purpose of conducting the electric power.
Ninth We claim the improved arrangement or construction of galvanic
battery where a large number of cells are to be employed as described under
the eighth head of this Specification.
Tenth We claim the enclosing of such galvanic batteries as emit vapors or
gases within a case which has a cover or lid that is made air-tight by means of
a water lute as before described. In the channel into which the edges of the
lid fit various solutions may be used in place of simple water to neutralize the
nature of the gases evolved thus for the nitric acid batteries a solution of lime
may be used. Plates of glass may also be let into the top of the cover whereby
the condition of the batteries may be examined. We also claim the use of
the air-tight arrangement for supplying and drawing off the liquids of such
batteries namely the introduction of tubes for such purposes through sheets of
vulcanized caoutchouc stretched tight or secured without tension over holes in
the case or cover of the battery the holes in the caoutchouc being cut smaller
than the tubes which are to pass through them and make a very air-tight but

page_text: flexible joint. Also we claim for the same purpose the use of a hydraulic trap
in any tube or trough used for supplying or discharging liquids to or from such
batteries as before described.
Eleventh We claim in regard to the treatment of iridium and of the manu-
facture of articles in that metal for the purpose of our Invention. First the
formation of a bed from the powder or grains of the iridium itself on which to
fuse the iridium by the passage of the disruptive discharge of electricity.
Second the use of a solid piece of iridium itself as the opposite electrode in the
process of fusion as herein-before described and Third the process of working
a solid piece of iridium into more perfect shape by connecting one part of it
with one wire of the battery (the positive) and working upon it by the disrup-
tive discharge to the positive iridium electrode as has been more particularly
explained.
Twelfth. We claim in regard to the equalizer before described First the use
of a platinum wire of sufficient thinness so arranged as to be immersible more
or less in mercury while the part out of the mercury is covered with water
(certain other imperfectly conducting liquids or liquid solutions may be used
instead of water as alcohol or dilute sulphuric acid) so that the electric current
to be equalized thereby being passed through the mercury and the part of the
wire that is above the surface of the mercuryis thereby resisted and diminished
more or less according to the length of wire remaining above the mercury
which wire may be moved when required (by the human hand for instance) for
the purpose of regulating or diminishing the electric current Second the com-
bination of the above apparatus with an electric regulator such as before
described so that the motion of the regulator shall make the wire to rise or fall
in the mercury and thus check and prevent any material variation in the
quantity of the electric current circulating in the conductors with which this
instrument is connected. Third the application of self-acting rheostats to
branch currents diverging from and rejoining a main conducting circuit so
that several lights can be maintained or operations performed by current
electricity from one battery or main circuit without the risk of variation or
accident from one affecting the action of the others. And Fourth we claim the
substitution of a number of fine springs (platinum wire heing the material
preferred) to make contact with the moveable helix of fine platinum wire in
place of mercury as a means of contact in the equalizer.
Thirteenth We claim the compensating dial-balance-galvanometer before
described, that is to say, We do not claim the application of an electric coil
with an iron rod moving in its centre for the purpose of galvanometry but we
claim in the combination of the coil and iron centre with the pinion working

page_text: into the rack affixed to the iron centre so as to indicate the motion of the
iron centre by the rotation of the pinion or its connections for the purpose of
incasuring the power of the electric current. Also the application of a partial
counterpoise weight on a wheel or arm fixed to the spindle of the said pinion
the weight being of such amount and applied in a line with such part of the
circumference of the pinion as shall have the most effect in making the spindle
of the pinion to pass through more equal arcs than otherwise when equal addi-
tions are made to the power of the electric current actually passing in circuit.
Also the application of the triode or appendage by which a free electrically
conducting connection can be made or broken at pleasure between the con-
ductors (such as the screw clamps) connected with the two ends of the cou-
ducting wire which is in the galvanometer. The object of the triode being to
make a freer passage e for the current than the galvanometer wire itself affords,
when the galvanometer is not required to give its normal indications. We
further claim the triode in its combination with quantity galvanometers,
that is, with such galvanometers as give a palpable indication of the change
when any resistance is added to or taken from the circuit of such electric
currents as they are fitted to measure. And finally the combination of the
triode with any intensity galvanometer (that is a galvanometer which gives
palpable indication of the change when the electro-motive force of the current
is increased or diminished) that may be preferred for use..
Fourteenth We claim the differential galvanometer before described that
is to say, the use of one or more lengths of insulated wire in coils or otherwise
so arranged in connection with a quantity-galvanometer that the coil of wire
can be included in the circuit, or the circuit be completed without it at plea-
sure as for instance by turning set screws for the purpose of obtaining an
indication of the intensity (or electro-motive force) of the current by observing
the quantitative indication of the galvanometer with and without the said wire
being included in the current. We also claim the arrangement of wire
when used to form a partial resistance to an electric current in a coil having
the reversed windings or having the flat form as herein-before described
for the purpose of neutralizing the electro-magnetic effects of the currents
in the said coil.
Fifteenth We claim in respect of the improved lamp movement before
described First the use of a screwed and slotted electrode shaft with a wheel
screwed on it ;thewhole being so arranged that the revolution of the wheel shall
cause a longitudinal motion of the shaft. Second the use of a spring support
for the said wheel or for the support of the shaft whereby the wheel sinks a
little when the electrodes are brought tightly into contact and in sinking its

page_text: teeth shall meet a stop to arrest its further motion so as to prevent too great
a pressure on the electrodes as already explained. Third the combination of an
elastic head (L) with the moving centre of the regulator, and Fourth the use
of a chain and barrel in place of a rack andpinionfor supporting and imparting
motion to the electrode shaft in certain electric lamps as has been herein-
before more fully explained with the special advantages attending it.
In witness whereof I the said William Edwards Staite have hereunto
set my hand and seal this Twentieth day of March in the year of our
Lord One thousand eight hundred and fifty.