IMPROVEMENTS IN MARINE AND OTHER STEAM ENGINES
Year: 1838

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
BARNETT HUMPHREYS, of Southampton, Civil Engineer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Thirtieth day of January, in the first year of Her reign, did, for
Herself, Her heirs and successors, give and grant unto me, the said John
Barnett Humphreys, Her especial licence, full power, sole privilege and
authority, that I, the said John Barnett Humpherys, my exors, admors, and
assigns, or such others as I, the said John Barnett Humphreys, my exors,
adñiors, 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 expressd, should
and lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN MARINE
AND OTHER STEAM ENGINES;" in which said Letters Patent is contained a
proviso that I, the said John Barnett Humphreys, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, to be inrolled in Her said Majesty's High Court of
Chancery within six calendar months next and immediately after the date of
the said in part recited Letters Patent, as in and by the same, reference being
thereunto had, will more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Barnett Humphreys, do hereby declare that the nature of my said
Invention, and the manner in which the same is to be performed, are
particularly described and ascertained in and by the following description

page_text: thercof, reference being had to the Drawing hereunto annexed, and to the
figures and letters marked thereon (that is to say) :-
My first improvement relates to a cock for opening and closing the steam
passage to and from the cylinder, and consists principally in equalizing the
pressure of the steam against the cone of the cock, and so removing the tendency
which that pressure has to make both cone and shell wear oval and become
leaky. To effect my object, I prefer making the steam pass in and out at
one end of the cone, commonly the smaller end, and making two passages
through the side of the one opposite each other, and of equal size and shape.
See the Drawing I, shewing sections of the cone and shell. In the shell will
be seen two passages on each side, those marked S being steam passages,
and those marked C leading to the condenser, and according as the two
openings in the cone correspond with S or C, or with the space between, so
will the steam be turned or the communication be shut off altogether. When
a large steam way and a rapid opening and shutting of it are especially
desirable, as for example in the short stroke cylinders of locomotive engines
either on land or water, I increase the number of openings in the cone, taking
care so to arrange them that the equilibrium of steam pressure against the cone
be not disturbed. It is evident that by making the openings through the sides
of the cone narrow, long, and numerous, any desired extent of steam may be
attained with comparatively very short distance of motion for the periphery
of the cone, and the rapidity of opening and shutting the steam way, &c. be
commensurate. The part V, inside the cone, is partly to fill up unnecessary
space e, partly to get a point near the end of the cone for stopping the key by
which the cone is turned, so as to reduce the tendency of the key to press
the cone towards one side, if the axis of the cone and key should not be
perfectly in a line. I retain the cone to its work by a set screw against the
key, or by other equivalent means; and in large engines I recommend a
stuffing box round the key with a small space between the cone and the
bottom of the stuffing box, and a small hole for communication between that
space and one of the condensing passages in the shell; this is merely to obviate
the unsightlyness of little weeps which, though without perceptible influence
on the efficiency of the engine, are unpleasant from the stop they make.
The cone may be moved by cams, tappits, excentric, or any other usual way;
but I claim an improvement on a method described in Treadgold's Treatise
on the Steam Engine (first edition) as " Field's Regulator". My improvement
consists in combining with it or adding to it another regulator, or part of one, to
reverse the motion of the crank shaft, and between the two a cylindrical part of
such diameter as will keep the cone of the cock in such a position as shall cut

page_text: off all communication between the cylinder and boiler and condenser,―see
Drawing II. Field's regulator admits the cutting off of the steam at any part
of the stroke; but where such nicety is not required, as for example in steam
boats or locomotive engines, I prefer dividing the regulator into steps affording
as many variations as may be desired, ascending or descending from one
to the other by slopes, and move the regulator along its shaft by hand only,
instead of by hand or governor, avoiding by this means the lateral pressure
against the roller or cam, excepting at the moment when the point at which
the steam is cut off, &c. is changed by hand.
The Drawing shews the regulator on a separate shaft; but it is evident that
it may be placed at once on the crank shaft, and that it may move a slide or
valves instead of the cocks, also that the spring for returning the motion may
be substituted by a weight, or by adding a second valve, and connecting each
pair of rollers opposite each other by any suitable frame,-see Drawing II,
Figure 1; but it is not quite so obvious that our improved regulator may be
made to control two engines that work one crank shaft, as is customary in
steam boats. I effect this by placing the frames which carry the rollers across
each other, adjusting the position of each frame to its respective crank, the
parts of the frames being, of course, so disposed that those of one frame shall
not interfere with those of the other, although all the rollers move in the same
plane. I believe this combination to be novel, and accordingly claim it, but
disclaim the exclusive use of the frames when used singly, as also the spring
or weight for returning the motion where only one roller or cam is used, such
having been long in common use; but I claim the carrying of such a pair
of rollers on rock. staffs connected by a link or links, as shewn in Figure 3,
and also the use of a rock staff, as shewn in Figure 4. The advantage of the
improved regulator is, that by moving it longitudinally by hand, I not only
alter the speed of an engine, but stop it altogether, or start it forwards or
backwards as desired. Thus the control of a steam boat, for example, may
be given to one will with instant obedience, a point of importance in moments
of danger; so simple and limited a motion as here required, effecting the
several purposes merely by the quantity of it (with the little power that suffices
for my improved steam cock or slide), may be easily and effectively connected
with an index on the standard of the tiller wheel, the usual starting lever
and disengaging means being, nevertheless, retained for the convenience of-the
men in the engine room.
The next improvement relates to a slide. Its chief objects are directness
of communication, reduction of friction, and the practicability of using very
large steam passages with less waste of steam than in the smaller passages

page_text: now generally adopted. To effect the last, the slide is so arranged that a
portion of steam passes from one side of the piston to the other side when the
piston is near the end of its stroke, sec Drawing III., where in Figure 1
the slide is shewn in section at the moment when it admits the steam from
one side of the piston to the other. The slide is kept in steam-tight contact
with the parallel planes between which it moves, either by metallic or other
packing, aided, when required, by springs or screws, or the like means are
applied to one of the planes; but though I use, as circumstances may make
convenient, any of the methods of packing commonly known, yet, of course, I
do not claim them; but I do claim the advantages resulting from my improved
slide, and particularly claim its property of saving the steam (or a great
portion of it,) required in the now common constructions to fill the passages,
and also to fill the necessary space in the cylinder above and below the piston
when the piston is at the extent of its stroke. This last object I also effect
by any valves or substitutes in common use, moved at appropriate times, also
by any of the means in common use froin which any practical engineer will
readily select such as suits his purpose, and I claim only the application of
such to this special object. I further effect this object by making near the
two ends of the cylinder one or more holes leading to passages to the top and
bottom, with a self-acting valve conveniently situated that shall let the steam:
pass only one way, and clain such when applied to this object.
In Drawing III., Figure 2, I have shewn (in section) how the above
arrangement may be applied to any engine already erected, the passage p
being cut in such a position that the piston passes it so far as the circum-
stances of each case shall require, and these circumstances will be chiefly
governed by the strength of the steam at the time of passing, by the dimen-
sions of the holes or sluices, and by the speed of the piston; but a very
beneficial effect will be produced without such nice adjustment, and will be
especially apparent in engines with short stroke, large passages, and great
speed of piston; for example, in steam carriages, the method of passing the
steam from one side of the piston to the other side in single-acting cylinders,
as has been long practised. I disclaim the object of this old practice, being
the substitution of steam pressure for atmospheric pressure, and so to avoid
the cooling of the cylinder; whereas the object of my arrangement is to save
the steam, or a great portion of it, that is now wasted in the passages and in
the cylinder at each end of the stroke.
My next improvement is in surface condensation; and Figure 3 in
Drawing III., shews a section of my arrangement for a high-pressure engine
without an air pump; B is a covered cast-iron cistern of quadrangular or other

page_text: convenient shape; C is a shallow chamber of copper or other metal slightly
vaulted on the top; the bottom of this chamber is pierced full of holes five
eighths of an inch diameter more or less, and in each hole a tube of copper
or other metal is fixed (there being as many tubes as can be conveniently
placed); the lower ends of these tubes are inserted, steam-tight in the bottom
of the cistern, the shallow chamber above being supported by the tubes; from
that chamber there rises a pipe D with a snifting valve on the end, so placed
as not to be unconvenient; in a steam vessel, for example, I place it in the
paddle box. While the engine is at work, cold water is constantly flowing
through the cistern, the tubes and shallow chamber above them being thereby
totally immersed. This cistern, with its tubes, &c., is placed on another cistern
with various partitions, as seen in the section; into this latter cistern the
steam is admitted at S, and rising into the tubes becomes condensed. The
extricated air, mixed with a very slight portion of vapour, passes through
the tubes and escapes by the snifting valve; at every third or fourth stroke
of the piston the condensed steam falls as water on the inclined partition, and
passes over or under the various vertical partitions to a pipe which conducts
it to the force pumps, whence it returns to the boiler. This circuitous passage
of the water is intended to retard the accumulation of dirty grease in the
boiler, and also to prevent the valves of the force pumps from becoming
choked from the same cause. This arrangement answers also for low-
pressure engine, or any engine with an air pump, by leading the pipe D
on the flat chamber to the air pump instead of to a snifting valve; but I also
simplify the construction by omitting the flat chamber above the tubes, and
closing each tube separately at its upper end, the extricated air, &c. being
taken off by a pipe or pipes rising through the coldest of the water in the
upper cistern, and leading to the foot valve of the air-pump. Though these are
my arrangements, yet I disclaim exclusive privilege for the greater part of
them, as being already before the public; I disclaim the tubes, merely as such,
or their substitutes, and disclaim the partitions in the lower cistern. But I
claim the entrance of the steam at the lower end of tubes, or their substitutes,
and the upward passage of the steam through them. And I claim the closing
of the upper end of the tubes, or their substitutes, when an air pump is used.
The advantages attending this mode of construction are, first, a greater rapidity
of condensation in consequence of the in-rushing steam meeting the water
resulting from the previous steam; secondly, the tubes are much longer
preserved free from any inside coating of dirty grease, and thereby retain
their full efficiency longer when an air pump is used. The tubes are quite as
efficient when closed at the upper end as they are with a passage through

page_text: them, while the construction is much simplified, the durability increased, and
particularly both construction and repairs much facilitated, and less expensive.
A further improvement which I claim, and recommend it particularly fol
very large engines, is the using of two condensers (or even more), videlicit,
one or more for the steam from above the piston, and the other or others for
the steam from below the piston. With such I find advantage in using
either two air pumps or one with double action, or a single air pump worked
by spur wheels and making two strokes for each stroke of the steam piston,
and communicating with each condenser alternately. This combination of two
or more condensers to one engine I claim; but I disclaim the regulating power
belonging to au air pump worked at double speed when properly adjusted,
such having been long before the public. The use of two or more condensers
affords a larger increment of time for the passage of heat through the metal
of the tubes, consequently more drops of water are formed in the tubes, and
better cooled, and many of them will be caught in the act of dropping from
the tubes by the in-rushing stean, the condensation is proportionately rapid,
and a less extent of condensing surface will suffice than is required in the
more languid method of admitting steam at the upper end of the tubes in
single condensers. When I use my improved slide with two or more con-
densers, I adapt to it two or more openings in its back seat, each leading to
its respective condenser. In order to replace the waste of water which
constant boiling and loss from unavoidable leaks occasion, I add, in any
convenient position, a small boiler or still, and heat it by leading the flue or
flues from the engine boiler through it, taking care that such flues have still
sufficient heat to cause the water with which such additional boiler is charged
to distil over and pass to the engine condenser or to the air pump where
such is used being already condensed on its passage by traversing a pipe
of sufficient length immersed in the water used for supplying the addi-
tional boiler; by this means the efficiency of the engines' condenser remains
unimpaired. I claim, however, only the combination of this additional boiler,
heated as above described, with a steam engines' condenser, and disclaim
similar means of distillation for general purposes, such having been long
before the public in various modes of adaptation to ships' cooking apparatus.
In witness whereof, I, the said John Barnett Humphreys, have hereunto
set my hand and seal, this Thirtieth of July, One thousand eight
hundred and thirty-eight.
JOHN BARNETT (L.s.) HUMPHREYS.

page_text: AND BE IT REMEMBERED, that on the Thirtieth day of July, in the
year of our Lord 1888, the aforesaid John Barnett Humphreys came before
our said Lady the Queen in Her Chancery, and acknowledged the Specifica-
tion aforesaid, and all and every thing therein contained and specified, in form
5 above written. And also the Specification aforesaid was stamped according to
the tenor of the Statute made for that purpose.