IMPROVEMENTS IN SHIPS' LOGS
Year: 1878

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 David Carroll, of Spring
Creek, in the County of Warren, and State of Pennsylvania, United States of
Americo
Sealed the 28th June 1878, and dated the 1st January 1878.
PROVISIONAL SPECIFICATION left by the said Alexander Melville Clark
at the Office of the Commissioners of Patents on the 1st January 1878.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN SHIPS' LOGS." [A communication
from abroad by David Carroll, of Spring Creek, in the County of Warren, and
State of Pennsylvania, United States of America.]
This Invention relates to an improved nautical log which indicates automatically
in suitable registers the forward and drift motion of the vessel, also the speed of
the same, so as to form in connection with the time a true record of the progress
and speed of the vessel.
The Invention consists of a tube with outer screw thread at lower end, which
passes down through the bottom of the vessel, and is screwed into the same. The
tube reaches up to the first deck, and forms thus a well through which the working
parts of the log are lowered until they extend below the bottom of the vessel.
In case of iron or other vessels where the well tube cannot be screwed in, the
same may be secured by flanged bolts and suitable packing, or in other reliable
manner.
The operating parts consist of an upper water wheel or screw whose shaft is
arranged parallel to the longitudinal axis of the vessel, of a second water wheel or
screw below the former, with the shaft at right angles to the axis of the vessel, and
of a speed indicator below the second wheel. The wheels and indicator turn in
supporting posts of horizontal discs which form the downward extension of a

page_text: central support or frame extending from the bottom of the vessel upward through
the well. The second wheel and the speed indicator gear by worm wheels of their
shafts with intermeshing bevel wheels of upright shafts, which at their upper ends
connect by suitable worm gearing with separate registering apparatus, of which
one is worked by the upper, the other by the lower wheel. The upper wheel
is revolved by the action of the water during the forward motion of the vessel,
while the leeway wheel is worked by the action of the water when the vessel is
drifting. The registering dial of the latter has two hands which run up to hundred
miles when the captain has to tally, the hands serving to indicate either way the
vessel is drifting by going forward or backward. The registering dial of the upper
wheel has three hands, and is arranged to indicate 1000 miles.
The registering apparatus may be arranged some distance from the well hole,
as the upper transmitting worm gear admits the working of the same in any
direction from the well hole.
Each registering apparatus is provided with a transmitting friction pulley and a
disc in connection with an adjusting screw and traversing nut, which admits the
changing of the friction pulley to greater or less distance from the centre of the
disc, and thereby the regulating of the motion of the hands, so that they indicate
the exact distance made by the vessel, causing the hands either to run faster or
slower, as required.
The speed indicator is constructed of four blades which intersect each other at
right angles. The indicator is hung for lateral motion to an inclined shaft, which
is pivoted by rectangular arms to the posts of the lowermost plate or disc. The
rear part of the shaft gears by a segmental pinion with a mutilated pinion mounted
on a vertical shaft that carries at its upper end a pointer which passes along an
arc-shaped and graduated plate. This swinging shaft is furthermore pivoted by a
forked rear portion to fixed side arms of the vertical shaft, so that this two-fold con-
nection of the indicator, which is also arranged with return springs, renders the
mechanism capable of indicating the speed for forward or backward motion of the
vessel, as well as for the drift motion of the same.
The
The forward motion is indicated by the raising of the pointer on a vertical scale
of the graduated plate, and the drift motion on a lateral scale of the same.
faster the vessel goes the higher the pointer is raised; and the faster it drifts, the
more the pointer is turned sideways by means of the segmental gear. Thus a
reliable record of the progress of the vessel, and of the speed of the same, may be
obtained at any moment, and in more convenient manner than by the devices at
present in general use.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Melville Clark in the Great Seal Patent Office on the
29th June 1878.
ALEXANDER MELVILLE CLARK, of 53, Chancery Lane, in the County of
Middlesex, Patent Agent. "IMPROVEMENTS IN SHIPS' LOGS." (A communication
from abroad by David Carroll, of Spring Creek, in the County of Warren, and
State of Pennsylvania, United States of America.)
This Invention relates to an improved nautical log which indicates automatically
on suitable registers the forward and drifting motion of the vessel, as also the speed
of the same, so as to form in connection with the time a true record of the progress
and speed of the vessel.
And in order that such Invention may be better understood and readily carried
into effect, I will now, with the aid of the accompanying Drawings, whereon similar
letters of reference indicate corresponding parts, proceed more particularly to describe
and ascertain the same.
Figure 1 of the accompanying Drawings represents a rear elevation of such
improved nautical log; Figure 2 a vertical transverse section of the same, taken on
line x, x, Figure 1, parallel to the longitudinal axis of the vessel to which the log
is applied; Figure 3, a top view of the log; and Figure 4 shews a detail view of
the adjusting screw for regulating the motion of the registering hands.
The Invention consists of a tube passing down through the bottom of the vessel
and forming a well hole below, in which two revolving wheels or screws are
arranged, the upper one of which is placed parallel to the longitudinal axis of the
vessel, and the lower one at right angles to the same.
The revolutions of the screws are indicated by suitable transmitting gearing and
registering apparatus placed inside of the vessel. Below the screws is arranged a
longitudinally and laterally swinging speed indicator that works a pointer along &
graduated plate.
Referring to the Drawings, A represents a tube with outer screw thread at lower
end, which passes through the bottom of the vessel and is screwed into the same.
Such tube reaches up to the first deck and forms a well, through. which the
working parts of the log are lowered until they extend below the bottom of the
vessel. In the case of iron or other vessels where the well tube cannot be screwed
in, the same may be secured by flanged bolts and suitable packing, or in any other
reliable manner.
The operating parts consist,-
Firstly. Of an upper water wheel or screw B, the shaft of which is arranged
parallel to the longitudinal axis of the vessel.
Secondly. Of a second water wheel or screw C, placed below the former, with the
shaft at right angles to the axis of the vessel.
And, Thirdly. Of a speed indicator D, placed below the second wheel. The wheels
and indicator turn in supporting posts E of the horizontal discs E', which form the
downward extension of a central support or frame E², extending from the bottom of
the vessel upward through the well, as shewn in Figures 1 and 2.
The wheels C and D gear by means of worm wheels on their shafts, with inter-
meshing bevel wheels on the upright shafts, which are connected at their upper
ends by suitable worm gearing, with duplicate registering apparatus F, of which
one is worked by the upper, and the other by the lower wheel. The upper wheel
is rotated by the action of the water during the forward motion of the vessel,
while the leeway wheel is worked by the action of the water when the vessel is
drifting. The registering dial of the latter has two hands which run up to hundred
miles when the captain has to tally, the hands serving to indicate either way the
vessel is drifting by going forward or backward. The registering dial of the upper
wheel has three hands, and is arranged to indicate one thousand miles.
The registering apparatus may, if preferred, be arranged at some distance from

page_text: the well hole, as the upper transmitting worm gear admits the working of the
same in any direction from the well hole.
Each registering apparatus F is provided with a transmitting friction pulley a
and disc b, in connection with an adjusting screw 6', and traversing nut a¹, which
admits the changing of the friction pulley to a greater or less distance from the
centre of the disc, and thereby the regulating of the motion of the hands, so that
they indicate the exact distance made by the vessel, causing the hands either to run
faster or slower, as required.
The speed indicator D is constructed of four blades, which intersect each other at
right angles. The indicator is hung for lateral motion to an inclined shaft d, which
is by rectangular arms d¹ pivotted to the posts E of the lowermost plate or disc E¹.
The rear part of shaft d gears by a segmental pinion e, with a mutilated
pinion e¹ of a vertical shaft e², that carries at its upper end a pointer e³, which
passes along an arc-shaped and graduated plate G. The swinging shaft d is fur-
thermore pivotted by a forked rear portion f to fixed side arms f¹ on the shaft e³,
so that this two-fold connection of the indicator, which is also arranged with return
springs, renders the mechanism capable of indicating the speed for forward or back-
ward motion of the vessel, as well as for the drift motion of the same.
The forward motion is indicated by the raising of the pointer on a vertical scale
on the plate G, and the drift motion on a lateral scale on the same. The faster the
vessel goes the higher the pointer is raised, and the faster it drifts the more the
pointer is turned sidewise by means of the segment gear. Thus a reliable record
of the progress of the vessel, and of the speed of the same, may be obtained
at any moment, and in a more convenient manner than by the devices at present
in general use.
Having thus fully described the nature of the said Invention, I would have it
understood that what I claim as new and desire to secure by Letters Patent is,―
Firstly. A nautical log constructed of water wheels or screws extending below
the bottom of the vessel, and placed at right angles to each other, with suitable
transmitting and registering apparatus conveniently placed in the interior of the
vessel for indicating the forward and drifting motions of the vessel, substantially in
the manner herein-before described and for the purpose specified.
Secondly. The nautical log constructed of water wheels or screws arranged below
the bottom of the vessel, one in the direction of the axis of the vessel, and the
other at right angles thereto, and of a speed indicator arranged for forward and
drifting motion below the screws in connection with suitable duplicate registering
apparatus and graduated scale, substantially as herein-before specified.
Thirdly. The combination of the longitudinally and laterally swinging and
spring-actuated speed indicator, formed of four rectangular blades, with the segment
and forked gear of a vertical transmitting shaft, having a pointer at the end, and
with an arc-shaped graduating plate having thereon a vertical and lateral scale
substantially as herein-before described, and for the purpose herein-before specified.
In witness whereof, I, the said Alexander Melville Clark, have hereunto set
my hand and seal, this Twentieth day of June, in the year of our Lord
One thousand eight hundred and seventy-eight.