Another part of the machine is a board upon which is placed the drawing showing the external shape of the proposed ship, and working over this board is a pointer connected by a system of rods and levers to the cutters just mentioned. The rough block of wax, then, having been placed upon the table and the to and fro motion set going, the attendant guides the pointer along the lines of the drawing, and as he does so the cutters so move as to carve away the soft wax into the precise shape of the model.
A little smoothing by hand is all that is necessary to complete the conversion of the rough piece of wax
into a perfect model. It is then placed in the water and ballasted with little bags of shot until it floats at just the correct depth, and finally a light wooden frame is fitted to it for the purpose of making the connection to the lever by which it is pulled along.
Thus, after much thought and experiment, the designs for a new ship are completed. Tracings are then made of them on semi-transparent paper or cloth, which tracings are then used as "negatives," from which a number of photographic prints are made, just as the amateur photographer makes prints from his negatives. At least that is how they used to be done, in a huge printing frame, but nowadays a machine is more often employed which passes the tracing or negative with a piece of photographic paper behind it slowly past an electric light, thus doing the work more quickly and more conveniently, for the drawings of ships are often very long and would either require an enormous frame or else would have to be made in pieces and joined together.
The prints are finally passed out to the works to be translated in terms of iron, steel and wood.
Perhaps the most important part of a shipyard is the mould loft, a large apartment on the floor of which the ship is drawn out full size. Then from these full-size drawings moulds or templets are made of wood or soft metal, showing the exact size and shape of the various parts. The moulds or templets go thence to the workshops, where the bars and plates of steel are cut to the right shape and perforated with holes, and some of the pieces are there joined together with rivets.
The Tripod Mast.
Here we see one leg of the tripod mast of a warship. These masts have greater stability and freedom from vibration than others. They are used for observation and range-finding, and have a fighting-top on which guns of small calibre are mounted. Here is shown a sailor carrying a wounded comrade.