which Appliance may be Used for Various Purposes.
Year: 1888

page_text: which Appliance may be Used for Various Purposes.
I, JOHN ANTHONY ROWE of No. 11 Spring Terrace, North Shields, in the County
of Northumberland, Engineer Surveyor &c. do hereby declare the nature of this
invention and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
My invention consists of a hydrostatic and hydro-dynamic arrangement whereby if
a part of the apparatus be moved from a certain definite horizontal position in relation
to the horizontal position of another part an indication of the amount of such
movement shall be given.-I use my apparatus for the purpose of ascertaining,
and if desired recording automatically the angles of oscillation of a rolling or pitching
ship at sea or I may use it in a ship of war to indicate the exact moment in the
movement of the heaving ship at which is attained the level in any desired direction
which the ship would have in perfectly smooth water and I may use this indication
with electrical appliances or otherwise to discharge a cannon or cannons with greater
accuracy than is at present attainable or I may use the appliance as a Seismograph
and automatically record tremors of the earth in the same way as I record the
oscillatory movements of a ship among waves at sea.
The details of my apparatus may be varied and its form may be also considerably
varied and I therefore desire it to be understood that I do not confine myself to any
special form or mere detail so long as the essential principle of my invention is
unaffected but for the sake of clearness in describing my invention itself I will
describe in detail a form of apparatus according to my invention as if no modification
of forin or detail could be made..
I am aware that it has been proposed and efforts have been made to measure the
oscillation of ships by pendulum arrangements of various kinds but from the inertia at
one point and the impetus stored in a pendulum at another point and from other causes
such efforts have not been successful and it has been found that such indications are
not reliable. The movements of a ship in a rough; sea are not only the movement
called rolling, and that called pitching, and that which results from the combination
of both but the bows of a ship struck forwards for instance by a heavy sea fall off

page_text: from the course, and with more or less assistance from the helm the ship is
brought back to her course or so far back as to fall off in an opposite direction; to
bring the ship back to her course by the helm does not however move the bows of
the ship sideways in the water into the right direction, but it causes instead the
stern of the ship to move sideways to the extent to which the bow has moved; so that 5
when the original course is exactly attained the ship is moving on a line parallel to
that line in which the ship previously moved but distant from the original line of
movement to the extent or nearly to the extent of the distance from that line to which the
bows were deflected.-All parts of the ship are thus moved sideways and the inertia
of any pendulum suspended in the ship must of necessity give an indication due 1
to that movement equivalent to an indication due to rolling, but which is in no
degree due to rolling and may be in fact in the opposite direction to that which
would have been given by rolling only. The point of suspension of the pendulum
being thus laterally moved the pendulum weight of course after inertia is overcome
follows the point of suspension and acquires impetus which is another approximately
equal source of error in the opposite direction. I am aware that many efforts have
also been made to measure the roll of a ship from each side of an exact vertical
line by means of a gyroscope but such effects have not been attended with success
from the fact that it has been impossible to discover the exact relation of the active
position of the gyroscope with the desired vertical line at the moment at which
the observation is to be taken.-Now I by my invention employ a hydrostatic
arrangement which exerts a continuous strain upon a spring and which by vertical
but not by mere lateral movement becomes a hydro-dynamic arrangement to add
to or diminish the tension on the spring and by suitable appliances to indicate.
record or otherwise utilize the force so brought into play. Before more fully.
describing an apparatus according to my invention I may give an illustration of one
of the modifications which I have before referred to as possible in the form of
apparatus employed.
am about to describe for clearness as I have said a form of apparatus as if it was
the only form possible, and in the apparatus so to be described it may be objected that
the column of mercury connecting the reservoir and the cylinder possesses inertia and
is capable of acquiring that momentum which I have referred to as a defect pertaining
to the pendulum arrangement but I point out that it is not necessary that such a
column of mercury should exist. I may by a slight change of form in the reservoir
and the cylinder, use a column of water or a column of air as the connecting medium
between the mercury in the reservoir and the mercury in the cylinder and thus reduce
the possible error in the ratio of the specific gravities respectively. As however the
description of such modifications would enhance very much the complexity of my
specification and they are mere matters of detail I mention this one only as an
illustration.
When it is desired to employ my invention for the purpose of indicating the roll of
a ship or the pitching of a ship or these movements combined, my apparatus is as
follows: employ a vertical standard attached to the ship (like a stanchion bar)
in a sheltered situation (preferably between decks or below the weather deck) and
upon it I mount a piece of board or a metal plate in such a way that it (the board,
metal plate or cross piece) may be revolved on the standard to any degree in any
direction. On the standard I place a collar for the cross piece to rest on, so that the
position of the cross piece in relation to the height of the standard remains invariable
and I place a set holt in the clamps which secure the cross piece to the standard so
as to be able temporarily to fix the cross piece either directly fore and aft with the
ship, or at any desired angle to that line. High up upon one end of the cross piece
I fix a small reservoir which I fill with mercury, and this reservoir is connected by
a pipe to a small cylinder situated low down at the opposite end of the cross piece
so as to be always at a lower level than the reservoir. In this cylinder I fit a free
moving piston and I connect the piston to a lever and spring so that the spring is in
tension to the extent due to the pressure caused by the difference of level of the
mercury in the reservoir and that in the cylinder.

page_text: When the vessel to which this apparatus is so fitted rolls or pitches a pointer
actuated by the piston remains nearly motionless relatively to the ship herself.-The
end of the lever is prolonged and points to a graduated scale of divisions of degrees
and minutes permanently fixed on the cross piece and it thus indicates with great
exactness the angle of the vessel at any given moment.
Permanent automatic records of the vessel's motions can be obtained by attaching
a pencil to the lever and causing it to bear upon paper wound round a cylinder
actuated by clockwork as is well understood.
When the instrument is to be employed for firing a cannon or cannons, at the
moment when the ship attains its exact vertical position I attach to the lever an
arrangement whereby an electrical contact is made between the ends of the lever
and an adjustable contact-breaker situate opposite to the lever ends.-The contacts
being adjusted to meet when the vessel is on a level keel.-These contact-breakers
are adjustable in a vertical direction and their movement up or down from the true
horizontal line hastens or delays contact so as to provide for retardation of action
in my apparatus or the reverse.-Although it is possible to fire a gun or a broadside
in either a descending or an ascending motion, I prefer to discharge the cannon
when the vessel is moving in one direction only, say when the movement of the
cannon about the vessel's centre of gravity is upward.-I couple electric wires into
electrical circuit with the guns to be discharged, and with the source of electricity,
and I have contact breakers at the guns themselves under control of the gunners.
When matters are thus arranged if it be desired to discharge a cannon at an
object situated at say 15 degrees, 15 minutes on the port bow, I set the cross piece
of my apparatus regulating the discharge of that cannon at the angle of 15° 15' to
port of the line of keel or nearly so, so that both roll and pitch will be indicated by
the action of the piston and lever.-The cannon or gun is then trained to such elova-
tion as is required for the range as if the ship were motionless, and being then
brought into line with the object, the contact at the gun is closed leaving to the
automatic contact breaker already described the completion of the circuit exactly at
the moment when the position of the piston indicates that the ship in the direction
specified is in a true horizontal line. Instead of a cylinder and piston I may employ
any convenient form of pressure gauge or a small pneumatic or hydraulic bellows
apparatus.
In the drawings A is the standard, B. the collar on which the cross piece turns,
C. the set screw fixing its angular position in reference to the line of the keel;
D. the reservoir of mercury first mentioned in the foregoing description, and E. the
pipe leading to the reservoir or cylinder last mentioned which is marked F.-G. is
the piston actuating by the pressure of the mercury the lever H. which the spring I.
tends to hold in a central position. H. is the lever and J. the scale which its point
moves over and on this scale or in proximity thereto may be fixed electrical contact
breakers or recording clockwork arrangements as is well understood.
my
Having now particularly described and ascertained the nature of said invention
and in what manner the same is to be performed I declare that what I claim is :-
The application of Hydro-static and Hydro-dynamic arrangements substantially as
described for the purpose of indicating recording or utilizing oscillatory movements in
ships and for other purposes.
Dated this Twentieth day of March 1000