AN INSTRUMENT TO SHEW THE VELOCITY OF A SHIP OR OTHER VESSEL PROPELLED THROUGH THE WATER BY WIND, STEAM, OR OTHER MOVING POWER
Year: 1849

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
LYON BERTHON, of Fareham, in the County of Hants, Bachelor of Arts, Clerk,
send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Twentieth day of June
(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 me, the
said Edward Lyon Berthon, my exors, admors, and assigns, Her especial
license, full power, sole privilege and authority, that I, the said Edward Lyon
Berthon, my exors, admors, and assigns, or such others as I, the said Edward
Lyon Berthon, my 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 and lawfully might make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, and the
Islands of Jersey, Guernsey, Alderney, Sark, and Man, and in all Her
Majesty's Colonies and Plantations abroad, my Invention of "AN INSTRUMENT TO
SHEW THE VELOCITY OF A SHIP OR OTHER VESSEL PROPELLED THROUGH THE WATER BY
WIND, STEAM, OR OTHER MOVING POWER;" in which said Letters Patent is contained
a proviso, that I, the said Edward Lyon Berthon, shall cause a particular
description of the nature of my said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal, to
be inrolled in Her Majesty's High Court of Chancery within six calendar

page_text: 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
Edward Lyon Berthon, hereby declare that the nature of the said. Invention,
and in what manner 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:
Figure 1 is a side elevation, partly in perspective, of the said instrument, for
shewing the velocity of a vessel through the water, supposing the same to be
detached from the vessel.
the water; it
A, A, is a flanged tubular socket, of brass or other metal, which is screwed
up to the flange into and through the bottom B¹ of the vessel inboard, and is
further secured by screw bolts passed through the flange. The bore of this
socket is about inch. About the middle there is a stop-cock C, the plug of
which is of the same bore as the socket. E is what I call a way tube, which
is passed down through the socket A and a stuffing box a into
is closed at bottom, with the exception of a side hole or port b. To the top of
the way pipe E there is fixed a crosshead F, which carries a forked rod G
reaching up to the deck, or any other convenient place of the vessel, and
terminating in a handle H, by which the rod and way tube may be raised or
lowered or turned round at pleasure. I is an index needle, which is attached
to the rod G a little below the handle H, and points to a horizontal segment
of a circle K, which is divided into degrees and points of the compass. Fixed to
the top of the way tube (E) is a piece of flexible hose L, the other end of
which is fastened to a fixed metal pipe M, 'extending from the hold of the
vessel to the spot at which the indicator is placed. This indicator consists of
a framework of wood about twelve inches long and three wide, which is swung
on a grimbal P, attached to some stanchion or support in the cabin or deck of
the vessel. Upon the front of the framework of the indicator are fixed two
parallel and vertical tubes of glass Q and Q¹, about 3 inch in diameter, half
filled with mercury, and communicating with each other by means of a piece
of capillary glass tube (c) below. Between the glass tubes Q, Q', is a sliding
scale R, graduated into divisions corresponding to nautical miles and tenths.
Thus, the first mile is represented by 04 inch, the second by 16, the third by
36, the fourth by 64, the fifth by 1 inch, and so on, increasing as the squares
of the velocity. The connection between the way tube below and the indicator
above is completed by another piece of hose N, a few inches long, one end of
which is attached to the top of the fixed pipe M and the other to the top of

page_text: the glass tube Q. Upon the highest part of the arch or the hose (Sec
Drawing) is a small suction valve a', furnished with a screw cap.
The mode of operation is as follows:-The way tube E is pushed by
the handle H through the socket A till its lower end projects a few inches
down into the water; the suction valve a¹ is then opened, when by the
escape of the air the water is allowed to rise to the external level in the
tubes E, L, M, and if the indicator be above the water line the rest
of the air in the tubes and hose is removed by suction, till the water
comes up to the suction valve, and also fills the part of the glass tube Q
not occupied by the mercury, completing a syphon of water, of which the short
limb rests upon the mercury in Q. Now, it is clear that the heights of the
mercury in the two tubes will depend upon the length of the column of water
in connection with the one marked Q, therefore before the vessel is put in
motion the zero point of the scale must be placed opposite to the level of the
mercury in the tube Q'; and when the vessel moves through the water with
the port of the way tube turned in the direction of motion, the influx of water
through the port will act so as to move upwards the whole column in the
pipes and hose, and depressing the mercury in Q will raise it correspondingly
in Q. The sliding scale must now be lowered, so as to stand with respect to
the new level in Q the same as it was when the vessel was at rest, when the
true height of the column of mercury raised by the force of the resistance due
to the velocity will be shown on the scale, being the sum of what the mercury
falls in Q and rises in Q, and the number on the scale opposite to the level in
Q¹ will denote the velocity of the ship in nautical miles and tenths of a mile per
hour. As every indication of the velocity by this instrument is dependent on the
aperture of influx (b) into the way tube E, being kept in a direct line with the
line of the vessel's motion, it is necessary to find this line, as the vessel may
not always be moving right ahead. This is easily done by turning the handle
H until this point is found, by the mercury then standing at the highest point.
Or, to save the trouble of this operation, there may be attached to the lower
end of the way tube E a tail float or vane, which always keeps the tube and
its aperture of influx (b) in the direct line required, whilst the angle between
this line and the ship's keel is constantly shown by the index needle on the
horizontal segment K, K. The construction of this vane and the mode of
attaching it to the way tube are shewn in Figure 2 (a side elevation), and
Figure 3 (a plan). The vane A* consists of a piece of tubing, flattened
sidewise into a wedge form, and it is centred, and turns vertically at its small
end on a cross pin d, inserted through the prongs of a fork projected from
the lower end of the way tube. When the vessel moves, this vane is from

page_text: the form of its construction thrown necessarily into the wake of the way
tube, and to whichever side it may be inclined subsequently to starting, by
changes of tack or other causes, it will communicate that change to the way
tube, and thus keep the aperture b constantly in the true line of the vessel's
motion.
And having now described the nature of my said Invention, and in what
manner the same is to be performed, I declare that what I claim, as constituting
iny said Invention, is, the instrument aforesaid for shewing the velocity of
vessels through water in the peculiar arrangement and combination of parts
and materials of which the same consists, that is to say, in the combination of
columns of water and mercury in the manner before described to shew the
velocity of a vessel through the water, and whether the same is used with or
without a tail vane, as before described.
In witness whereof, I, the said Edward Lyon Berthon, have hereunto set
my hand and seal this Twentieth day of Decomber One thousand