AN IMPROVED LOG
Year: 1863

page_text: LETTERS PATENT to Ernest Bazin, of Angers, in the Department of the
Maine et Loire, in the Empire of France, Engineer, for the Invention of
"AN IMPROVED LOG."
Sealed the 14th July 1863, and dated the 21st January 1863.
PROVISIONAL SPECIFICATION left by the said Ernest Bazin at the
Office of the Commissioners of Patents, with his Petition, on the 21st
January 1863.
I, ERNEST BAZIN, of Angers, in the Department of the Maine et Loire, in
the Empire of France, Engineer, do hereby declare the nature of the said
Invention for "AN IMPROVED LOG," to be as follows:-
My Invention consists in the use of the syphon as principle and means for
measuring the distance run by a ship, and at the same time indicating the
rate of speed. The syphon which I use is a large bent tube, the extremities
of which pass by an orifice in the bull of the ship and plunge into the water
near the keel. The two extremities of this pipe or syphon are bent back in
the direction of the length of the vessel one one way and one the other, so that
when the ship is in motion the orifice at one end serves to admit water, and
the orifice at the other end permits its. exit. On the neck or upper bent
part of the syphon which is fixed to the deck is a box, which should be her-
metically closed, and contain an. indicator, with index to mark the speed of
the ship, and also a meter for measuring the distance run in a given time. It
will be readily comprehended that there will be a communication between
the indicator and the meter with the current; which (as' hereafter explained)
passes through the interior of the syphon. This communication will be

page_text: established by means of openings made in the upper part or neck of the
syphon. Inside the neck of the syphon I place a screw, which when rotating
will, by toothed gearing, set the meter at work.
It will be evident from the preceding that my improved log essentially
consists of a long bent pipe extending from the deck and plunging its two
ends into the water near the keel of the vessel. The water necessarily rises
in the pipe to the evel of the water line, but if by means of a suction pump
I entirely fill this pipe, and then close all communication between the
exterior air and the box fixed on the neck, as before mentioned, I have as it
were primed a large syphon. My pump is in communication with the her-
metically closed box containing the indicator and the meter, and this box is
in communication with the tube or syphon by the openings left for that
purpose. A water level or gage indicates when the priming is complete, so
that no water may be drawn into the box, which should always be filled with
air, inasmuch as it encloses the toothed gearing. The priming ended, and the
two branches of the syphon being equal and plunging in the same body of
water, it will be understood that the apparatus is in repose; but immediately
the ship begins to move a current will be formed in the pipe, the rapidity of
which current will be about equal to the speed of the ship, less the friction in
the pipe. This current causes the screw to turn, and consequently the
toothed gearing of the meter. The indicator is a simple piston attached to a
spring lever. This piston receiving the action or force of the current causes
the lever to travel a lesser or greater distance, and indicate on the dial the
rate of speed.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Ernest Bazin in the Great Seal Patent Office on the
20th July 1863.
TO. ALL TO WHOM THESE PRESENTS SHALL COME, I, ERNEST
BAZIN, of Angers, in the Department of the Maine et Loire, in the Empire
of France, Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-first day of January, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Ernest Bazin, Her special licence, that I, the said
Ernest Bazin, my executors, administrators, and assigns, or such others

page_text: as I, the said Ernest Bazin, my executors, administrators, and assigns,
should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom of
Great Britain and Ireland, the Channel Islands, and Isle of Man, an Inven
tion for "AN IMPROVED LOG," upon the condition (amongst others) that Ị,
the said Ernest Bazin, my executors or administrators, by an instrument
in writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and in
what manner the same was to be performed, and cause the same to be filed
in the Great Seal Patent Office within six calendar months next and imme-
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Ernest Bazin, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the follow-
ing statement, reference being had to the accompanying Sheets of Drawing
forming part of this my Specification, and to the figures and letters of
reference placed thereon, similar letters denoting similar parts at each of the
Figures respectively :-
The improved log, the subject of my Invention, is an apparatus registering
by the aid of a meter the distance run by a ship, and at the same time
shewing its rate of speed by means of an indicator. This combined meter
and indicator I term a "logometer." The principle of my apparatus is based
on the well-known theory of the syphon, and the novelty of my Invention lies
principally in the application of this principle to registering the distance run
by a ship, and at the same time indicating the rate of speed on a dial, the
complete suppression of transmission, the small space occupied by the appa-
ratus, its arrangement, and the means provided for easily regulating the
working of the instrument.
My improved log is applicable not only to ships, as above set forth, but also
to measuring streams. I will first describe the construction and arrangement
of my improved log, referring to the Sheets of Drawing on which the modi-
fications to which I have been guided by experience are indicated in red ink.
A bent tube a, b, c, d, e, with branches of equal length, having the form of
a syphon, as shewn, Figure 2 (Sheet 1) fitted to a vessel shewn in section,
Figure 1 shews that if at the horizontal part c of this tube and in its interior
is placed a screw, and on the upper part of this same tube is fitted a meter in
connection with the screw, and any current be established within the tube,
such current will evidently set the screw in motion, and consequently the

page_text: entire wheelwork of the meter. The two equal branches of the syphon
plunging into the same medium, and being bent at their extremities in
opposite directions to prime the apparatus, there remains but to cause the
water to rise in the tubes by means of a pump (a). In a state of repose the
water only rises in the tubes to the height of the water line, and during the
operation of priming a level indicator (9) marks the level which it is desirable
to obtain. This operation ended, on referring back to Figure 2 (Sheet 1) it
will be easily understood that the bent tube completed by a hermetically
closed box at its upper part, has been primed as a syphon might have been,
but the branches are equal, and plunge in the same level of liquid, in which
state no effect can be produced; but as soon as the vessel begins to run its
speed will produce in the tube a current at a, this current will rise to 6 (as
indicated by the arrows on the Drawing) set the screw at work at c, descend
at d, and finally cscape ate by the outlet hole. To prevent the entrance of
marine plants into the tubes 1 place blades or gratings at the entrance and
outlet holes. The Figures 3 and 4 (Sheet 1) represent the ensemble of the
meter (A), the indicator (B), and the water level (C), the whole contained
within a hermetically closed box communicating with the tubes of the syphon
at the upper part c. This box is placed on the deck of the ship, and as
shewn in the Drawing glasses permit the dials to be read. The indicator
works as follows:-A jointed disc s, Figure 1 (Sheet 2) is suspended in the
interior of a tube, and at its upper part c, this disc serves to estimate the
strength of the current established in the primed tubes, and determined
by the progressive motion of the ship, and it will be readily understood that the
stronger the current the more the disc which opposes it will yield to the
pressure, As indicated by the Drawing it is evident that the different
variations in the speed of the current will be rated on the dial of the indi-
cator (2) Figure 1, Sheet 2) by the aid of an index or hand (v) mounted
on an axle the angular movement of which is in the relation of 1 to 2 with
that of the disc,
.
And I would here, while treating of the indicator of the rate of speed,
allude to an improvement marked on the Drawing in red ink. A special
dial indicating the yards will be consulted when it is desired to ascertain how
many knots the vessel is running, presuming 16 yards to make a knot, if
during one minute by the glass the index arrives at 64 yards the ship will
be running 4 knots. This is a novel method of heaving the log and ascer
taining the speed of the ship. I will now describe the working of the
apparatus. Presuming that by means of the pump (Sheet 2, Figure 2)
communicating by a pipe, with the hermetically closed box containing the

page_text: neter and the indicator) the apparatus has been primed, the ship attaining a
certain speed will have created in the tubes a current of equal speed less the
rictions, and naturally set the meter at work. To arrive at the suppression
of the frictions, I use a moderator, which the thread of the screw being
calculated for a superior speed, will moderate the current, until the working of
the instrument is perfectly regulated. As regards the meter the screw
receiving the impulsion of the current from the direction indicated by the
arrows, Figure 1 (Sheet 2) will necessarily rotate by the aid of a pinion, this
rotary movement will be transmitted to a meter, and by a combination of
wheelwork the distance run will be marked upon 4 or 5 dials, the first of
which may indicate the yards, and the fifth hundreds of miles as may be
desired. I have ascertained by experiment that when the ship is moving
slowly the air contained in the water will disaggregate, form into globules, and
being compressed into the hermetically closed box cause the water level to
lower; now if the water level descend below the screw the current will no
longer pass, and the apparatus will require priming afresh, to avoid which I
use a reservoir above the curved part of the syphon, and by this elevation of
the water level feeding or priming is rarely required; A', moderating register;
A", modified logometer; f, screw; g, thread on screw shaft; h, i, j, wheel-
work; k, m, n, o, indexes.
Having now described the nature of my said Invention, and the means by
which I carry the same into practical effect, I desire it to be understood that
I do not claim the exclusive use of any of the parts herein-before described
and shewn, taken as parts, and not used in combination, and for the purposes
of my Invention, which I declare to be, and I claim the combination of
parts forming in their combination, apparatus by which I register the distance
run by a ship, indicate its rate of speed, or measure a stream, the whole
essentially as herein-before described, and illustrated in the accompanying
Sheets of Drawing.
In witness whereof, I, the said Ernest Bazin, have hereunto set my
hand and seal this Seventeenth day of July, in the year of our Lord
One thousand eight hundred and sixty-three.
Witness,
DARNIS.
E. BAZIN. (L.S.)