IMPROVEMENTS IN SHIPS' LOGS
Year: 1879

page_text: LETTERS PATENT to Alexander Melville Clark, of 53, Chancery Lane, in the
County of Middlesex, Patent Agent, for the Invention of "IMPROVEMENTS
IN SHIPS' LOGS." A communication from abroad by Alexander Gordon, of
the City, County, and State of New York, United States of America.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark at
the Office of the Commissioners of Patents on the 10th September 1879.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN SHIPS' LOGS." [A communication
from abroad by Alexander Gordon, of the City, County, and State of New York,
United States of America.]
"
The object of this Invention is to furnish an improved ship's log which shall be
so constructed as to count and register the number of knots run out in a quarter of
a minute, and also indicate the knots by sound, which shall be so constructed that
it can be readily used by one man, and which shall be simple in construction and
reliable in use.
The Invention consists in the combination of mechanism for measuring and
registering the length of line that runs off the reel in the combination of mechanism
for sounding the gong as each knot of the line runs out; in the combination of
mechanism for starting the clockwork and throwing it out of gear automatically
at exactly the end of a quarter of a minute; and in the combination of the brake,
spring, and push pin with the reel for controlling the unwinding of the line from
the said reel, all as hereinafter fully described. The operating mechanism is
enclosed in a box having at one end a handle and in its other end a slot for the
line to run through. The outer end of the line is attached to the drag, and its
other end is attached to and wound on a reel pivoted to a frame secured to and
within the box. A brake is suspended from the said frame and is pressed against
the reel by a pin passing in through the end of the box, or by a pin and lever, and
is withdrawn by a spring. The line passes out between two rollers, the lower one
being faced with rubber and pivoted to the frame that supports the reel; the
upper roller, which may also be faced with rubber if desired, being pivoted to the
ends of the lower arms of two bent levers which are pivoted at their angles to the
said frame. The ends of the upper arms of the levers are connected by a cross bar
to which is attached the end of a spiral spring, the other end of which is connected
:

page_text: with a set screw so that the tension of the spring may be readily adjusted as may
be required to cause the outward passage of the line to revolve the rollers without
slipping, so that the amount of cord run out may be accurately measured upon the
said rollers. This construction also allows the upper roller to yield to allow any
unevenness or knots in the line to pass through. To the journal of the lower
roller is attached a worm or endless screw gearing with a worm wheel on the end
of a shaft that revolves in bearings attached to a lever which is pivoted to the
frame of the clock work. The clockwork is constructed and driven by a spring in
the usual way.
To the said shaft is attached a worm or endless screw which gears
with a worm wheel attached to a sleeve that works loosely upon the projecting
shaft of the reel, and to the outer end of which is attached a pointer that moves
around a dial, visible outside the box or case, and points to the division marks of
the said dial, the said division marks representing knots. To the outer end of the
sleeve of the said worm wheel is also attached a ratchet wheel, the teeth of which
are equal in number to the number of division marks upon the dial, and rest
against a projection or pin upon the spring hammer handle of a gong, so that the
said gong may be struck as each knot is run out. The gong may be placed without
or within the box as may be desired. Upon the lever in which the shaft is
mounted, as before mentioned, is formed an arm having a point or knife edge at its
end which rests upon the face of a notched wheel, and drops successively into the
notches formed in the said face. This wheel is attached to such a shaft of the
clock work that the said wheel may be exactly a quarter of a minute in moving;
through the space of one notch so that the clock work will be stopped instantly at
the end of a quarter of a minute. As the clock work is stopped the worm wheel
on the end of the shaft (before referred to as gearing with a worm on the journal of
the lower of the pair of rollers, between which the line passes), is thrown out of
gear with said worm by a spring which presses against the lever, in which is
mounted, as before mentioned, the shaft on whose end the worm wheel is, so that'
the line can be drawn in without operating the mechanism. The reel is turned to
wind up the line by a balanced crank attached to the end of its shaft. The end of
the said lever projects through a slot in the end of the box near the handle, so that
it can be conveniently operated to release the clockwork instantly at the proper
time. With this construction the clock word is started when the drag is thrown
out by operating the said lever to withdraw its arm from the notched wheel and
allow the clockwork to start, which clockwork is stopped automatically at the end
of a quarter of a minute, and the number of knots is read from the dial, or they
may be known by counting the strokes of the gong. The line is then drawn in,
and the pointer is turned back to the zero mark of the dial, leaving the machine
ready for instant use when again required.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by 4
the said Alexander Melville Clark in the Great Seal Patent Office on the
9th March 1880.
ALEXANDER MELVILLE CLARK, of 58, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN SHIPS' LOGS." A communication
from abroad by Alexander Gordon, of the City, County, and State of New York,
United States of America.
The object of this Invention is to furnish an improved ship's log which shall be
so constructed as to count and register the number of knots run out in a quarter

page_text: of a minute, and also indicate the knots by sound, which shall be so constructed
that it can be readily used by one man, and which shall be simple in construction
and reliable in use.
The Invention consists in the combination of the two rollers, the bent levers, the
spring, the adjusting screw, the two sets of worms and worm wheels, the shaft and
lever, and the pointer and dial, with the line for measuring and registering the
length of line that runs off the reel, in the combination of the two rollers, the bent
levers, spring, and adjusting screw, the two sets of worms and worm wheels, the
shaft and lever, and the ratchet wheel, with the line, and the spring hammer handle
of the gong for sounding the said gong as each knot of the line runs out; in the
combination of the arm, the notched wheel, the clock work, and the spring with
the two rollers, the bent levers, spring, and adjusting screw, the two sets of wornmis
and worm wheels, the shaft and lever, and the pointer and dial, for starting the
clockwork and throwing it out of gear automatically at exactly the end of a quarter
of a minute; and in the combination of the brake, spring, and push pin with the
reel for controlling the unwinding of the line from the said reel, all as hereinafter
fully described. Figure 1 of the accompanying Drawings is a front view of the
improved log, part of the box or case being broken away; Figure 2 is a horizontal
section of the same taken through the line x, x, Figure 1; Figure 3 is a vértical
longitudinal section of the same taken through the line y, y; Figure 2; Figure 4 is
a vertical longitudinal section taken through the line z, z, Figure 2.
The same
letters of reference indicate corresponding parts in all the Figures.
3
A represents a box which encloses the operating mechanism. To one end of the
box A is attached a handle B, and in its other end is a slot for the line C to run
through. The outer end of the line C is attached to the drag, which drag is not.
shown in the Drawings, and its other end is attached to the reel D, pivoted to a
frame E secured to and within the box A. F is a brake suspended from the frame
E, and which is pressed against the flanges of the reel D by a pin H passing in
through the end of the box A, or by a pin and lever, and is withdrawn from the
said flanges by a spring G. Two arrangements of the spring G are shown in,
Figure 4. The line C passes out between two rollers I, J, the lower one I of which
is faced with india rubber, and is pivoted to the frame E that supports the reel D.
The upper roller J, which may also be faced with rubber if desired, is pivoted to
the ends of the lower arms of two bent levers K. that are pivoted at their angles to.
the frame E. The ends of the upper arms of the levers K are connected by a cross
bar, to which is attached the end of a spiral spring. L, whose other end is connected.
with a screw M so that the tension of the spring L may be readily adjusted, as
may be required, to cause the outward passage of the line C to revolve the rollers
I, J, without slipping so that the amount of cord run out may be accurately.
measured upon the said rollers. This construction also allows the upper roller to
yield to allow any unevenness or knots in the line to pass through. To the journal
of the lower roller I is attached a worm or endless screw N gearing with a worm
wheel O formed upon or attached to the end of the shaft P. The shaft P revolves
in bearings attached to the lever Q, which is pivoted to the frame R of the clock
work S. The clock work S is constructed and driven by a spring in the usual way.
To the shaft P is attached a worm or endless screw T which gears with a worm
wbeel U attached to a sleeve that works loosely upon the projecting shaft of the
reel D, and to the outer end of which is attached a pointer V that moves around a
dial W on the outside of the box or case and points to the division marks of the
said dial, the said division marks representing knots. To the outer end of the
sleeve of the worm wheel U is also attached a ratchet wheel X, the teeth of which
equal in number the number of division marks upon the dial. The teeth of the
ratchet wheel X rest against a projection or pin formed upon or attached to the
spring hammer handle Y of the gong Z so that the said gong Z may be struck as
each knot is run out. The gong Z may be placed without or within the box A as
may be desired. Upon the lever Q is formed an arm g¹ having a point or knife
edge formed upon or attached to its end, which rests upon the face of the wheel A¹

page_text: and drops successively into the notches formed in the said face. The wheel A¹ is
attached to such a shaft of the clockwork S that the said wheel A¹ may be exactly
a quarter of a minute in moving through the space of one notch so that the clock-
work will be stopped instantly at the end of a quarter of a minute. As the
clockwork is stopped the worm wheel O is thrown out of gear with the worm N
by a spring B¹ which presses against the lever so that the line can be drawn in
without operating the mechanism. The wheel is turned to wind up the line C by
a balanced crank C¹ attached to the end of its shaft. The end of the lever Q
projects through a slot in the end of the box A, near the handle B, so that it can be
conveniently operated to release the clock work instantly at the proper time. With
this construction the clock work is started when the drag is thrown out by operating
the lever to withdraw its arm q' from the notched wheel A¹ and allow the clock
work to start, which clock work is stopped automatically at the end of a quarter
of a minute, and the number of knots is read from the dial W, or they may be
known by counting the strokes of the gong. The line is then drawn in, and the
pointer V is turned back to the zero mark of the dial W, leaving the machine
ready for instant use when again required.
Having described the nature of the said Invention and the manner of performing
the same, I declare that what I claim as the Invention to be protected by the
hereinbefore in part recited Letters Patent is,-
1st. The combination of the two rollers I, J, the bent levers K, the spring L, the
adjusting screw M, the two sets of worms and worm wheels N, O, and T, U, the
shaft and lever P, Q, and the pointer and dial V, W, with the line C for measuring
and registering the length of line that runs off the reel D, substantially as herein
shown and described.
2nd. The combination of the two rollers I, J, the bent levers, spring, and
adjusting screw K, L, M, the two sets of worms and worm wheels N, O, and T, U,
the shaft and lever P, Q, and the rachet wheel X, with the line C and the spring
hammer handle Y of the gong Z for sounding the said gong as each knot of the
said line C runs out, substantially as herein shown and described.
3rd. The combination of the arm q', the notched wheel A', the clockwork S, and
the spring B with the two rollers I, J, the bent levers, spring, and adjusting
screw K, L, M, the two sets of worms and worm wheels N, O, and T, U, the shaft
and lever P, Q, and the pointer and dial V, W, for starting the mechanism and
throwing it out of gear automatically at exactly the end of a quarter of a minute,
substantially as herein shown and described.
4th. The combination of the brake, spring, and push pin F, G, H, with the reel D
for controlling the unwinding of the line C from the said reel D, substantially as
herein shown and described.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Eighth day of March, in the year of our Lord One
thousand eight hundred and eighty.
A. M. CLARK. (L.S.)