A NEW TIDE-PREDICTING MACHINE. 239 
No. 5.—DESCRIPTION OF A TIDE-PREDICTING 
MACHINE. 
By Captain A. INGLIs. 
(Read, January 10, 1898.) 
Tus machine differs from any other one that I know of in its 
requiring only one set of gearing. The principle on which the 
machine is founded is as follows:—A number of wooden tem- 
plates are cut, each in the form of a sine curve, representing one of 
the tidal components; these waves are of different lengths, but are 
all pushed along vertically side by side at the same rate, being 
supported by a frame or carrier moved forward by a rack and 
pinion. A number of vertical plungers rest in a line on the top 
of these templates, and are moved up and down as the curves 
progress forward. The motion of the plungers are then com- 
pounded by means of a fine wire passing over pulleys at the top 
of each one, and under fixed pulleys between adjacent ones. The 
compound portion is then communicated to an indicator, which 
moves up and down alongside a vertical scale. The forward 
movement of the carrier on components moves the clock, which 
indicates the time. Thus the time and height can be read off at 
once. 
GENERAL Description.—The machine consists of a rectangular 
frame, 4 feet long, 29 inches wide, and 10 inches high; in the 
lower part of it is a groove in which the carrier moves. Across 
the top at the middle of the frame is a beam with vertical 
slots in it for the rods or plungers to move up and down in, 
between each slot in the beam a pulley is fixed. In front of the 
beam is the recorder with a scale on it, in this recorder is a 
traveller, which carries a pencil on one side and pointer on the 
other, the one for tracing the curve and the other for showing 
the height on the scale. In front of the frame, between it and 
the recorder, is a vertical slide holding the paper on which the 
curve may be traced. The carrier is a flat frame with grooves in 
the upper part of it,in which the curves or templates representing 
the different components are fixed. On the lower side is a rack, 
which, when acted on by a pinion, gives the carrier a rectilinear 
motion through the frame. Underneath the carrier, and across 
the frame, is a shaft with a crank outside. On this shaft three 
pinions are fixed ; these give motion to the carrier, vertical slide, 
and the clock respectively. The clock is fixed on top of the frame 
above the shaft. 
