IMPROVEMENTS IN APPARATUS FOR NAVIGATIONAL DEEP SEA SOUNDINGS
Year: 1876

page_text: LETTERS PATENT to Sir William Thomson, Knight, of Glasgow College,
Doctor of Laws, and Professor of Natural Philosophy in the University and
College of Glasgow, in the County of Lanark, North Britain, for the In-
vention of "IMPROVEMENTS IN APPARATUS FOR NAVIGATIONAL DEEP SEA
SOUNDINGS"
PROVISIONAL SPECIFICATION left by the said Sir William Thomson at the
Office of the Commissioners of Patents on the 1st September 1876.
Sir WILLIAM THOMSON, Knight, of Glasgow College, Doctor of Laws, and
Professor of Natural Philosophy in the University and College of Glasgow, in the
County of Lanark, North Britain. "IMPROVEMENTS IN APPARATUS FOR NAVIGA-
TIONAL DEEP SEA SOUNDINGS."
The object of this Invention is to facilitate the measurement of the depth of water
below a ship at any time without reducing the speed.
The apparatus for measurement consists of a narrow glass tube closed at one end
and open at the other, and provided with a preparation as herein-after described for
marking the portion of the interior which has continued to be occupied by air under
the pressure experienced by it when the tube is sent to the bottom, or nearly to the
bottom of the sea. This tube is virtually a pressure gauge, and it must be of so
narrow a bore that there shall be no splashing of the liquid in it during the sound-
ing process, which consists as follows:-The glass tube is guarded by an outer
metal tube and attached to the sounding line at a short distance above the sinker,
or it may be placed in the sinker made tubular for the purpose, but I prefer having
the gauge tube separate from the sinker, as it is thus less exposed to violent shocks,
whether in striking the bottom or from the surface of waves when being hauled in.
The form of sinker which I prefer is a round iron bar of from an inch to an inch
and a half diameter, and three or four feet long, with a hollow in its lower end to
receive an arming of soap, tallow, or wax, for bringing up a specimen of the bottom.
I have found bluffer forms of sinker apt to break the wire, probably from concus-
sion on the surface of a wave
The sinker may be let go to the bottom by allowing enough of stray line, accord-

page_text: ing to the ordinary method of deep sea soundings, and may be hauled in again by
hand in the usual manner, but I prefer performing the sounding operation by
my method of using pianoforte wire or other strong steel wire coiled on a wheel
with a brake applied to the wheel to control the egress of the wire, and
handles, or a ropo, or band, for turning the wheel in the other direction to
haul in the wire. The framework carrying the wire wheel is placed near the
stern of the ship, the sinker and pressure gauge hanging down below the taff-
rail, and the wheel held fast to begin with. Then suddenly the wheel is let
go with such force on the brake as shall produce a constant resistance of a few
pounds, say about 4 lbs, against the ogress of the wire. The moment the sinker
strikes the bottom.the wheel stops, or nearly stops for a few seconds of time. Then
the brake is forced down to prevent the wheel from running on again. When the
wheel is thoroughly stopped a pawl is dropped into a ratchet attached to it, the
brake is cast off, and hauling in commenced
A
In sounding from a steamer running at 14 knots, in water of 70 fathoms
depth, I have found the sinker to draw about 195 fathoms of wire off the
wheel, and to take about 40 seconds of time to reach the bottom The hauling
in by two men turning the wheel easily by handles occupied about 7 minutes
counter is attached to the wheel, and by noting its reading at the instant when the
sinker, touches the bottom the depth may be instantly declared if there has been
sufficient experience in sufficiently similar circumstances of apparatus, speed of ship,
and weather; but until there has been sufficient experience to form a trustworthy
table of the depths corresponding to the observed readings of counter in the actual
circumstances the depth is to be determined from examination of the gauge tubo
when brought on board again after the performance of a sounding
To prepare the gauge tube so that a mark may be left, its open mouth may be
smeared with oil, or with some fine powder or mixture; I have found simply smear-
ing it with lycopodium powder to answer sometimes very well, though not to be
always satisfactory I therefore prefer the following:-The interior of the tube is to
be lined all round, or part of the way round, through its whole length, or as much
of its whole length as may be needed, with a preparation which shall mark the
distance that liquid has been forced into the tube. The preparation may be white-
wash, or size-colour, or ink, or aniline blue, diied upon the inside of the tube, or it
may be a substance, such as red prussiate of potash, adapted to show by chemical
action how far the inside of the tube has been wetted by liquid forced into it
secure adhesion of the substance to the side of the tube, and constancy and clearness
of the mark produced on it, I find a narrow slip of paper gummed or pasted along
the tube internally on one side to answer exceedingly well, but I have also obtained
perfectly good results with a sensitive substance, such as red prussiate of potash,
adhering directly to the glass
To
The mark may be produced simply by sea water, straining or dissolving away
the sensitive substance; but I have obtained more satisfactorily clear marks by in-
troducing other substances than sea water in the liquid entering the tube under the
influence of pressure. For this purpose I use a cup or thimble round the lower or
open end of the gauge tube containing ink, or aniline blue, or sulphate of iron
solution, or other liquid suitable for leaving its mark. Sulphate of iron has the
advantage of being very expensive, and it gives a sharp and strong mark
when a strip of paper impregnated with red prussiate of potash constitutes the
internal preparation of the tube to receive the mark. Farther, to prevent the
marking liquid from running up the interior of the tube by capillary attraction,
I coat the whole interior with shellac, varnish, or glue, or gum, dried upon it
before attaching the paper ship or other preparation to receive the mark. To
quickly dry the inside of the gauge tube in the course of preparation air is driven
through it.
If the preparation of the gauge tube is performed at sea the tube may be open at i
each end to allow air to be blown or sucked readily through it; and when it is dry

page_text: and the preparation completed one end may be stopped by a brass mounting
cemented to the tube provided with a stopper or plug to be screwed upon or into
it. But I prefer having the gauge tubes prepared on shore and put in sufficient
number on board ship ready for use. With this plan no brass mounting is neces-
sary, one end of the tube being simply sealed by the glass blower, and a fine metal
tube may be used for driving a drying current of air along the whole interior surface
of the glass tube. To tell the depth from the mark on the gauge I use a scale
graduated to fathoms according to the known law of compression of air. This scale
may be attached to the metal guard tube which guards the gauge during the
process, but I prefer, ospecially for soundings by night, having it separate in a well
lighted place on the deck, or in the wheel-house or chart room of the ship. The
moment the guard tube is brought to the taffrail the glass gauge is drawn out of it
and carried to the scale, where the depth is instantly read off.
When it is desired to obviate the necessity of previous chemical or other prepara-
tion of the tube I use a pressure tube open at each end and provided with valves,
one at the lower end to let sea water enter when the sinker is going down, the other
at the upper end to let air escape when it is drawn up; each of these valves remain-
ing closed except when urged in its opening direction by a small definite amount of
force.
To preserve the steel wire from rust I use quicklime, or caustic soda, or oil, to
facilitate the application of which to the wire I use a roller, which may be mounted
on the same framework as the coiling wheel. The lower side of this roller dips in
quicklime or caustic soda, and carries round some of the liquid particularly to the
lower side of the wire just before it is coiled upon the main wheel. To preserve the
wire from rust when the apparatus is out of use, the wheel is taken off its bearings
and closed up in a properly arranged vessel, in which it is kept wholly immersed
under oil or caustic; fixed cheeks guide the wire when being hauled in, so that it
may fall on a breadth of the roller somewhat less than that of the main wheel, to
insure that the wire shall be laid properly in the groove. I also use a fixed curved
metal guide, leaving the roller tangentially, and end vertically over the water a
short distance abaft the taffrail to guide the wire when it is nearly all hauled in,
and when therefore the incoming part comes to be so nearly vertical that it is not
convenient to let it first touch the roller.
The wire before it reaches the roller or curved guide may be dried by a cloth or
cotton waste held by hand, and also guided so as to be coiled in the proper position
on the groove of the main wheel, or proper guiding mechanism may be used for
this purpose, but in respect to simplicity of the apparatus a hand may be preferred,
and certainly suffices for whatever guiding or drying may be wanted.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Sir William Thomson in the Great Seal Patent Office on the 1st
March 1877.
Sir WILLIAM THOMSON, Knight, of Glasgow College, Doctor of Laws, and
Professor of Natural Philosophy in the University and College of Glasgow, in the
County of Lanark, North Britain. "IMPROVEMENTS IN APPARATUS FOR NAVIGA-
TIONAL DEEP SEA SOUNDINGS."
The object of my said Invention is to facilitate the measurement of the depth of
water below the ship at any time without reducing her speed.
The apparatus for measurement consists of a narrow glass tube, closed at one end
and open at the other, and provided with a preparation as herein-after described
for marking the portion of the interior which has continued to be occupied by air
under the pressure experienced by it when the tube is sent to the bottom, or nearly
to the bottom of the sea. This tube is virtually a pressure gauge, and it must be

page_text: of so narrow a bore that there shall be no splashing of the liquid in it during the
sounding process, which consists as follows:-
The glass tube is guarded by an outer metal tube, and attached to the sounding
line at a short distance above the 'sinker, or it may be placed in the sinker, made
tubular for the purpose; but I prefer having the gauge tube separate from the
sinker, and lashed to the rope connecting the sinker to the sounding wire herein-
after described, as it is thus less exposed to violent shocks, whether in striking the
bottom, or from the surface of waves when being hauled in. The form of sinker,
which I prefer, is a round iron bar of from an inch to an inch and a half diameter,
and three or four feet long, with a hollow in its lower end to receive an arming of
soap, tallow, or wax, for bringing up a specimen of the bottom. I have found
bluffer forms of sinker apt to break the wire, probably from concussion on the
surface of a wave.
The sinker may be let go to the bottom by allowing enough of stray line, according
to the ordinary method of deep sea soundings, and may be hauled in again by hand
in the usual manner; but I prefer performing the sounding operation by iny method
of using pianoforte wire, or other strong wire, coiled on a wheel, with a brake
applied to the wheel to control the egress of the wire, and handles, or a rope, or
band, for turning the wheel in the other direction to haul in the wire. The
framework, carrying the wire wheel, is placed near the stern of the ship, the sinker
and pressure gauge hanging down below the taffrail, and the wheel held fast to begin
with. Then suddenly the wheel is let go with such force on the brake as shall
produce a constant resistance of a few pounds, say about 4 or 5 lbs. against the
egress of the wire. The moment the sinker strikes the bottom the wheel stops, or
nearly stops, for a few seconds of time. Then the brake is forced down to prevent
the wheel from running on again. Hauling in is then commenced, the first effect of
which is to cast off the brake, after which but little resistance to hauling in, beyond
the weight of the wire and sinker, is experienced.
In sounding from a steamer, running at 14 knots in water of 70 fathoms depth,
I have found the sinker to draw about 195 fathoms of wire off the wheel, and to
take about 40 seconds of time to reach the bottom. The hauling in by two men
turning the wheel easily by handles occupied about 7 minutes. A counter is
driven by the wheel, and by noting its reading, at the instant when the sinker
touches the bottom, the depth may be instantly declared, if there has been sufficient
experience in sufficiently similar circumstances of apparatus, speed of ship, and
weather; but until there has been sufficient experience to form a trustworthy table
of the depth corresponding to the observed readings of the counter in the actual
circumstances, the depth is to be determined from examination of the gauge tube
when brought on board again after the performance of a sounding.
To prepare the gauge tube, so that a mark may be left, its open mouth may be
smeared with oil, or with some fine powder or mixture. I have found simply
smeaning it with lycopodium powder to answer sometimes very well, though not
to be always satisfactory. I therefore prefer the following:-The interior of the
tube is to be lined all round, or part of the way round, through its whole length,
or as much of its wholo length as may be needed, with a preparation which shall
mark the distance that liquid has been forced into the tube. The preparation
may be whitewash, or size colour, or ink, or aniline blue, dried upon the inside of
the tube, or it may be a substance, such as red prussiate of potash, adapted to show
by chemical action how far the inside of the tube has been wetted by liquid forced
into it. To secure adhesion of the substance to the side of the tube, and constancy
and clearness of the mark produced on it, I find a narrow slip of paper, gummed or
pasted along the tube internally on one side, to answer exceedingly well, but I have
also obtained perfectly good results with a sensitive substance, such as red prussiate
of potash mixed with starch, adhering directly to the glass.
The mark may be produced simply by sea water, staining or dissolving away the
sensitive substance; but I have obtained more satisfactorily clear marks by intro-

page_text: ducing other substances than sea water in the liquid entering the tube under the
influence of pressure. For this purpose I fill the outer guard tube or the hollow
sinker with ink, or aniline blue, or sulphate of iron solution or other liquid suitable
for leaving its mark. Sulphate of iron has the advantage of being very inexpensive,
and it gives a sharp and strong mark when a strip of paper impregnated with red
prussiate of potash is used, or when the prussiate of potash adhering to the glass
constitutes the internal preparation of the tube to receive the mark. Farther, to
prevent the marking liquid from running up the interior of the tube by capillary
attraction, I coat the whole interior with shellac varnish, or glue, or gum, dried
upon it before attaching the paper slip when a paper slip or other similar pre-
paration is used to receive the mark. To quickly dry the inside of the gauge
tube in the course of preparation, air is drawn throught it.
If the preparation of the gauge tube is performed at sea, the tube may be open
at each end to allow air to be blown or sucked readily through it; and when it is
dry, and the preparation completed, one end may be stopped by a brass mounting
cemented to the tube, provided with a stopper or plug to be screwed upon or into it.
It is however preferred that the gauge tubes be prepared on shore and put in
sufficient number on board ship ready for use. With this plan one end of the tube
may be simply sealed by the glass blower, and a fine metal tube may be used for
driving a drying current of air along the whole interior surface of the glass tube.
To tell the depth from the mark on the gauge, I use a scale graduated to fathoms,
according to the known law of compression of air. This scale may be attached to
the metal guard tube, which guards the gauge during the process, but I prefer,
especially for soundings by night, having it separate in a well lighted place, on the
deck or in the wheel house, or chart room of the ship. The moment the guard tube
is brought to the taffrail, the glass gauge is drawn out of it, and carried to the
scale where the depth is instantly read off.
When it is desired to obviate the necessity of previous chemical or other pre-
paration of the tube, I use a pressure tube open at each end and provided with
valves, one at the lower end to let sea water enter when the sinker is going down,
the other at the upper end to let air escape when it is drawn up, cach of these
valves remaining closed except when urged in its opening direction by a small
definite amount of force.
To preserve the wire from rust when
taken off its bearings and closed up in a
under oil, or caustic, soda, or quick lime.
hauled in, so that the wire may be left
the drum.
the apparatus is out of use, the wheel is
vessel, in which it is kept wholly immersed
Fixed cheeks guide the wire when being
clear of the flanges whilst being coiled on
The wire before it reaches the drum may be dried by a cloth or cotton waste held
by hand, and also guided so as to be coiled in the proper position on the groove of
the main wheel; or any suitable mechanism may be used for this purpose, but in
respect to simplicity of the apparatus a hand may be preferred, and certainly
suffices for whatever guiding or drying may be wanted.
In using the sounding machine in very cold weather when water carried up by
the wire and rope is liable to freeze on the drum, the drum which is hollow is pro-
vided with a removable screw plug so that hot water may be poured into it, and
thereby thaw or melt the ice or prevent freezing from taking place
And in order that my said Invention may be properly understood, I now proceed
more particularly to set forth the system, mode, or manner, in or under which the
same is, or may be used, or practically carried into effect, reference being had to the
annexed Sheet of Drawings, and to the letters and figures marked thereon, that is
to say
-
On the Sheet of Drawings hereunto appended, Figure 1 is a side clevation;
Figure 2, a front elevation; Figure 3, an elevation of the rear end; and Figure 4,
a plan of the sounding machine with the attachments constituting my said
Invention.

page_text: .
As shewn by the Drawings the apparatus consists of a sole or bed A, whercon
the drum B on which the pianoforte wire is wound is supported in brackets or
frames C, a handle D being secured on each end of the shaft E carrying the drum.
A taugent screw F is situated on the shaft E and geared with a worm wheel a,
which is fixed upon a horizontal shaft b held between two vertical plates c, d, con-
nected together by ties e and supported by pinching screws or their equivalent in a
slotted arm g fixed to one of the side frames o. On the shaft b is a spur pinion h
geared with a wheel i carried on a shaft also supported by the plates c, d
Fingers or pointers fare secured upon one end of each shaft b, k, which work round
dials marked upon the plate c, as seen at Figure 3, and the number of revolutions
made by the drum B in paying out the wire whilst taking soundings, and conse-
quently the length of wite so paid out is thus ascertained The end of the wire
wound upon the drum B has secured to it an iron ring or link m to which a length
of rope, preferably about a fathom and a half, is also attached. The sinker n is
secured to the other end of this rope, and between the sinker and the ring or link
the casing tube or shield o, which is preferably made of brass containing the glass
tube prepared in either manner herein-before described is lashed to the said length
of rope, preferably at a position which will leave sufficient rope above it to make
one turn round the drum when the wire is wound up. The rope is so wound round
the drum B in order to prevent or to lessen the tendency which the wire on account
of its spring has to unwind itself from the drum
Figure is a full size longitudinal section of the glass tube; and Figure 6, a
similar view of the brass casing tube or shield, which is provided at its upper end
with a removable cap or cover p, and at its lower end with a bar 7 of vulcanite or
other elastic material against which the lower end of the glass tube rests, and which
from its elastic nature prevents the tube from being broken by coming in contact
with the harder end of the casing whilst inserting the tube therein. The lower end
of the casing tube or shield o is composed of a plug, which being removed leaves
the tube free to be cleaned or probed out by wire in the event of the lower end
becoming choked by mud or fragments of glass broken by accident. On one side
of the drum B is a pulley G, around which a cord H is passed, one end thereof
being attached to a weighted lever or bar I which is centred on the sole A at J,
Figures 3 and 4 of the Drawings. The other extremity of the cord H passes over
a pulley K carried in vertical frames L formed on or fixed to the said pulley, and
whereto the cord is secured. A lever M. carrying an adjustable weight N is also
formed on or fixed to the pulley K, and this weight in conjunction with the cord H
and the weighted lever or bar I acts as a brake on the drum B, both whilst the
wire is being paid out when sounding, and when the sinker n has reached the
bottom.
Whilst the wire is being paid out the lever M is raised into the position
indicated by the line a, Figure 1, so that the weighted lever or bar I by its down-
ward pull on the cord H shall hang freely between the upper and lower stops
limiting its range. It is so weighted as to exert a downward pull of about 7 lbs.,
which gives a sufficient retarding force, say of from 4 lbs. to 6 lbs. on the drum to.
keep the wire taut and to stop the wheel when the sinker reaches the bottom.
When the wheel is therefore seen to stop the lever M is allowed to fall into the
horizontal position shown on the Drawings, whereby the weighted lever or bar I is
raised against its upper stop and an amount of retarding force is exerted on the
drum B, sufficient to prevent it from again commencing to rotate. Instantly after
this the handles are used to coil back the wire on the drum. By the first backward
motion of the drum the weighted lever I is let down until it rests on its lower stop,
and the other weighted lever M is raised into the position indicated by the line y,
Figure 1. Thus the retarding force of the cord against the continued motion of the
drum in coiling on the wire is almost completely annulled. In this position the
centre of gravity of the weight N is nearly over the axis round which it turns, and 5
therefore the brake exerts but very small retarding action on the continued motion.

page_text: of the drum B in hauling in the wire. When the wire has again been all wound
on the drum the glass tube is removed from the casing tube o, and applied to the
scale or "wand," seen full size at Figures 7 and 8 of the Drawings, and by this scale
or "wand which is divided into fathoms," the depth is ascertained by the length to
which the coating of the glass tube has been acted upon and discoloured upwards
from its lower end by the direct action either of the water passing in through the
holes q in the upper end of the casing tube, or by the action of the water forcing
the solution of iron, or other reacting solution contained in the casing tube or
shield o, up into the chemically prepared glass tube.
The screw plug X is that which is provided for the purpose, when removed, of
allowing hot water to be poured inside the wheel to melt or thaw any ice that may
become frozen thereon in cold weather.
The caps are preferably formed with slots leading out of each of the holes
through which the tightening screws v¹ pass, the object of which is to enable them
to be quickly removed, so that the wheel with the wire coiled thereon may be
"unshipped," or removed from its bearings, or placed therein with a very little loss
of time.
'
By simply turning each of the thumbscrews v¹, so as to release their pressure
on the caps v, the caps are slid out from beneath them and they are preferably
connected by pieces of chain (hanging loosely) to the frames, so that by being thus
permanently attached thereto the caps are prevented from being lost.
In the sinker n the portion marked n' at the bottom indicates the recess for
holding the arming of soap, tallow, or wax, herein before referred to.
At Figure 9 is shown in longitudinal section the other arrangement of gauge
tube, or that in which the water forced into the tube during its descent in the
sea is retained in the tube. The tube, in this case, is provided at each end with
a mounting containing a valve which opens inwards. As the tube descends the
lower valve is opened and the water enters the tube, at the same time compressing
the air into the upper part of the tube. When the bottom is reached and hauling
in is commenced, by which the tube is caused to move through the water upwards,
the lower valve shuts and retains the water which had entered there through
whilst it was being sunk and the pressure of the sea acting upon the upper valve
causes it to open, thus allowing the air gradually to escape as the tube approaches
the surface. Thus the pressure of the an within the tube is kept constantly in
balance with the pressure of the sea outside the tube, so that no danger of bursting
the tube by pressure of the contained air is incurred.
This last arrangement of the gauge tube, like that herein-before described, is
when used placed within a shield or casing having a slit along one side, on the
edge of which is marked a scale showing the depth in fathoms by the height of the
contained column of water seen against the scale.
Having now described and particularly ascertained the nature of my said
Invention, and the system, mode, or manner, in or under which the same is or may
be used or practically carried into effect, I would observe in conclusion, that I do
not clann as novel and original the sounding wheel or drum, neither do I claim the
use or application of pianoforte or other wire in making soundings; but what I do
consider novel and original and therefore claim as the Invention secured to me by
the herein-before in part recited Letters Patent is,―
First. The gauge tube prepared on its interior in any of the modes, substantially
as hercin-before described, for the purpose of obtaining a definite mark showing the
height to which liquid has been forced into the tube, thereby indicating the depth
to which the gauge has been submerged below the surface of the sea.
Second. The gauge tube fitted with valves at its upper and lower ends, for the
purpose of allowing the water to enter and compress the air as the tube is being
sunk, and to retain the water and allow the compressed air to escape as the tube
is being hauled in, substantially as herein-before described and shown at Figure 9
of the annexed Sheet of Drawings.

page_text: Third. The brake with its mechanism for automatically binding and releasing
the drum accordingly as the drum is turned a short distance in one direction or the
other, substantially as herein-before described and shown at Figures 1, 2, 3, and 4,
of the annexed Drawings.
In witness whereof, I, the said William Thomson, have hereunto set my
hand and seal, this Twenty-seventh day of February, One thousand eight
hundred and seventy-seven.
WILLIAM THOMSON. (L.S.)