IMPROVED MEANS OR APPLIANCES FOR MEASURING AND INDICATING THE RATE OF MOTION OF A SHIP OR OTHER BODY THROUGH WATER AND THE SPEED OR VOLUME OF CURRENTS OF WATER OR OTHER LIQUIDS
Year: 1882

page_text: LETTERS PATENT to Joseph Armstrong of Wellington Street New Swindon in
the County of Wilts Engineer, for an invention of "IMPROVED MEANS OR
APPLIANCES FOR MEASURING AND INDICATING THE RATE OF MOTION OF A SHIP
OR OTHER BODY THROUGH WATER AND THE SPEED OR VOLUME OF CURRENTS
OF WATER OR OTHER LIQUIDS"
.
PROVISIONAL SPECIFICATION left by the said Joseph Armstrong at the
Office of the Commissioners of Patents on the 25th March 1882.
JOSEPH ARMSTRONG of Wellington Street New Swindon in the County of Wilts,
Engineer, "IMPROVED MEANS OR APPLIANCES FOR MEASURING AND INDICATING
THE RATE OF MOTION OF A SHIP OR OTHER BODY THROUGHT WATER, AND THE
SPEED OR VOLUME OF CURRENTS OF WATER OR OTHER LIQUIDS,"
My Invention relates to apparatus for accurately ascertaining the rate of motion
of a ship or other vessel or body through water by persons on the said ship vessel
or body and also for accurately ascertaining the speed or volume of currents in
rivers, pipes, or other ways.
In order to ascertain the speed of a vessel or body passing through water I
adopt mainly the following:-I fix in a convenient position on the vessel, by
preference near the keel of a ship or boat; an ejector or ejectors so constructed that
as the ejector passes through the water a partial vacuum is obtained in the cjector
or ejectors and pipes connected therewith, which lead to any convenient position or
positions on the vessel, in order that the speed of the vessel through the water may
be ascertained at a glance, or registered in various ways which I will hereinafter
describe.
•
I. construct the ejector or ejectors (by preference two, one situated on each side
of the keel) with what I may term outside cones, in order that as the vessel passes
through the water, the water does not enter the ejector, the object being to
prevent the fouling of the vacuum space by seaweed, fish, or other extraneous
matter.

page_text: The indicators are placed in any convenient position and are constructed after
the principle of an ordinary Bourdon tube, vacuum gauge or mercury column or
water column or aneroid barometer, or a piston moving in a cylinder, the said
piston being opposed by a spring or any other convenient instrument for measuring
fluid pressure. These or some of the aforesaid indicators having been set to
indicate in proportion to the speed will rarely require re-setting, and the speed can
be ascertained by inspection of the said Indicator.-The registering apparatus I
arrange thus: I place a clock or other time measuring instrument inside a drum
or cylinder, the said clock or measuring instrument causing the cylinder or drum
to revolve proportionately to the time; I fix around this drum or cylinder paper or
other recording substance and on the outside I arrange a style pencil pen or electric
needle,, which is moved in one direction in proportion to the amount of speed
obtained, and the drum or cylinder moving in the opposite direction, a diagram can
be obtained which will correctly register the speed in, relation to the time.
By making the cylinder or drum a magnet or a conductor of intermittent currents
of electricity governed by the said clock and the outside needle a magnet, a series
of dots. would be marked on the paper, which would accurately register the speed,
or the paper may be marked by a hand caused by the clock to fall upon the paper
at regular intervals.
When used to indicate the speed of currents of water or other fluids, or to
measure and register the amount of water passing through pipes or other ways, an
apperatus similar to that herein before described may be used, but I prefer to place
in a convenient position in the pipes or ways the afore described ejector, forming a
partial vacuum, which will draw air or a fraction of the fluid by which the partial
vacuum is formed, past or through a turbine, water-wheel, screw, or other convenient
arrangement by means of which a set of indexes or dials are made to revolve and
indicate the amount of fluid that passes the ejector or through the pipes or ways.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Joseph Armstrong in the Great Seal Patent Office on the
25th September 1882.
"
JOSEPH ARMSTRONG of Wellington Street New Swindon in the County of Wilts,
Engineer, IMPROVED MEANS OR APPLIANCES FOR MEASURING AND INDICATING
THE RATE OF MOTION OF A SHIP OR OTHER BODY THROUGH WATER AND THE
SPEED OR VOLUME OF CURRENTS OF WATER OR OTHER LIQUIDS"
My Invention relates to apparatus for accurately ascertaining the rate of motion
of a ship or other vessel or body through water by persons on the said ship vessel
or body, and also for accurately ascertaining the speed or volume of currents in
rivers, pipes, or other ways.
In order to ascertain the speed of a vessel or body passing through water, I adopt
mainly the following arrangements
I fix in a convenient position on the vessel by preference near the keel of a ship

page_text: or boat an ejector or ejectors so constructed that as the ejector passes through the
water a partial vacuum is obtained in the ejector or ejectors and pipes connected
therewith, which lead to any convenient position or positions on the vessel in order
that the speed of the vessel through the water may be ascertained at a glance or
registered in various ways which I will hereinafter describe.-I construct and so
arrange the ejector or ejectors that the end of the nozzle or nozzles is turned in the
opposite direction to which the vessel is moving, in order that the water shall not
enter the ejector, the object being to prevent the fouling of the spaces by seaweed,
fish, or other extraneous matter.-A partial vacuum is obtained in the ejector or
ejectors which is proportionate with the speed of the vessel moving through the
water. This partial vacuum has only to be measured when the speed can be
accurately ascertained
In order to prevent the rolling motion of the vessel from affecting the indications,
I prefer to place one ejector on each side of the keel, and couple the vacuum
chambers together with a pipe. In this pipe a three way valve is placed so that one
or both ejectors may be used independently or together, in order that one may be a
check upon the other. The pipes leading from the valve I carry around the sides
of the hull or directly upwards, but I prefer to carry them around the sides of the
hull, in order to prevent the indications being affected by severe rolling, for then
one vertical height will compensate for the other. And an arrangement could be
added in which a chamber is exhausted by the action of the ejector or ejectors
through an aperture constructed so small that the amount of exhaustion would
vary little between each roll or pitch of the said vessel.-The pipes I then lead to
the indicators, which are placed in any convenient position and are constructed
after the principle of an ordinary Bourdon tube or vacuum gauge or mercury
column or water column or aneroid barometer, or a piston moving in a cylinder,
the said piston being opposed by a spring or any other convenient instrument for
measuring fluid pressure. I also add when necessary what may be called an
intensifier, so arranged that a large diaphragm piston, mercury column, or their
equivalents, is opposed by a smaller diaphragm piston mercury column or their
equivalents; the pressure of the atmosphere acting on the larger area overcomes
the pressure of the atmosphere acting on the smaller area and, the vacuum obtained
is therefore greater behind the smaller area than it is behind the larger area-The
larger diaphragm I connect on to the pipe leading from the ejector or ejectors, and
the smaller diaphragm or its equivalent I connect with the indicators and registering
apparatus. Another part of my Invention has for its object the alteration of
pressure from what may be called a vacuum into that of compressed air.
In order that the nature of my Invention may be clearly understood I will now
proceed by reference to the accompanying drawings to further and particularly
describe in what manner same is to be performed:-
DESCRIPTION OF DRAWINGS..
Fig. 1 represents the section of the hull of a ship with the indicating apparatus
attached-E and E2 are ejectors placed on each side of the keel. V₁ and V2 are
three-way valves placed in the pipes, in order that one ejector may be worked
independently or together with the indicating and registering apparatus.-A I are
the automatic intensifiers, which prefer to use when a low vacuum is formed by
the ejectors-V P is the vacuum pipe. S I, is the speed indicator, RI is the
registering indicator.
Fig. 2 E. is the ejector-S H is the small hole.-EC is the exhausted chamber
Fig. 3. V P is the vacuum pipe.-PP is the pressure pipe-D' is the vacuum
diaphragm D2 is the compressed air diaphragm-L, the lever
Fig. 4. E is the ejector-E O the ejector orifice.
In Fig. 1. I place two ejectors E¹. and E2 on each side of the keel, they are
connected together by a pipe which leads through a three way valve V2, the pipes
leading from these ejectors run around the sides of the hull into valve V' a branch

page_text: is then carried into what I may term the intensifier A', and from the intensifiers &
pipe is led to the speed indicator and the registering indicator; these indicators may
be put in any convenient part of the vessel
In Fig. 2 is shown a portion of a chamber from which the air is exhausted by
one or more ejectors, the opening leading from the ejector or ejectors to the chamber
is contracted at S H to such an arca that the rolling motion of the vessel will not
materially affect the degree of exhaustion in the chamber, although it may do so in
the ejector..
In Fig. 3 is illustrated´an apparatus for utilizing the varying power obtained
from the ejector or ejectors (which is proportionate to the speed) to more accurately
indicate and register the speed of the vessel by compressed air instead of by a
vacuum or rarefied air when a low vacuum is obtained by the ejector or ejectors.—
The vacuum pipe VP is in direct communication with the ojector or ejectors, and
the pressure pipe P P is in direct communication with the registering apparatus
The lever L by its construction assists the atmospheric pressure acting on the
diaphragm D¹ to compress the air acting against diaphragm D² to such an extent
that the variation of the pressure in the pipe V P compared with the pressure of
the atmosphere is exaggerated in the pipe PP in proportion as the levers and areas
of the diaphragms are arranged.
0.
In Figure 4, I illustrate an ejector of the shape which is found to work best in
practice. The friction between the air or water in motion and the water at rest
being so much increased in consequence of the greater superficial contact.
Having thus described the nature of my Invention and the manner of performing
the same, I would have it understood that I do not confine myself to the exact
arrangement or details herein specified and described as such may be varied as
circumstances may demand, but what I claim as improvements in apparatus for
measuring and indicating the speed of a body through water are:-1st the use of
an ejector or ejectors so constructed that the water does not flow through same when
in motion, substantially as described.
2nd. The registering and indicating apparatus in combination with ejector or
ejectors, substantially as described.
In Witness whereof I the said Joseph Armstrong have hereunto set my hand
and seal this twenty third day of September in the year of our Lord one
thousand eight hundred and eighty two.
-Witness
T. MORGAN
21 Cockspur Street'
:S.W.
JOSEPH ARMSTRONG. (L.S.)
A