By Dan Beard
Fig. 327.
In the autumn much fun may be had with a Baby Ballista, which is constructed in this way: From a two-inch plank make a base plank of any size that may suit your fancy, say four feet long. Near the front end of the baseboard (C, Fig. 327) and at equal distances from the edge, saw and chisel out two notches, four by two inches each.
Fig. 328.
These mortises are for the uprights A and B (Fig. 327) to fit in, where they must be secured by screws or nails. Make A and B of two by four inch plank. Next select a board that is broad enough to form the spreader D (Fig. 328). D is simply a board a trifle longer than C is broad and a little wider than A or B. In each end a mortise is cut so that the distance between the edges of the rectangular notches or mortises is exactly the distance between the uprights A and B where they join the base, plank C. Fasten D in place near the tops of A and B by driving nails above and below.
Fig. 329.
Take a piece of good, strong clothes-line and bring the ends around the uprights A and B, and tie them securely together so that the rope forms a loop which is tight enough to support itself. Now from a long, flat piece of strong wood make the bat E (Fig. 329), make it a little longer than the base-board C. Take a short stick, somewhat thicker through than the bat-stick E, and with it thrust between the sides of the loops of rope, wind the stick over and over, twisting the rope G until it is very tight. Now carefully slip the end of the bat-stick E into the space occupied by the thicker stick you have used as a winder, and remove the short stick, leaving E in place. The spring of the rope will force the bat-stick into the position shown in Fig. 329, and if the upper end of the bat is pulled down and suddenly let go it will strike the stretcher D with a resounding whack.
Fig. 330.
From an old tomato-can, or any other convenient source, secure a piece of tin, which may be flattened out and cut into a square. With a nail, make four holes near the center. Next cut four slits in the tin, from the corners of the square to four points near the center of the tin. At the long end of the bat-stick (E, Figs. 330 and 331) place the piece of tin, near enough to the end of the stick to allow free play for a trigger that is fastened on the end of the base-board (see Fig. 331). After you have adjusted the tin in its proper place, with a pencil thrust through the nail-holes in the tin, mark the spots on the back-stick underneath, and with a gimlet or a hot iron bore four holes at the points marked. Then fasten the tin to the bat-stick with a piece of wire. Next bend up the edges of the tin, allowing them to overlap each other until they form a cup or basin-shaped chamber for holding the shells (Figs. 330 and 331).
Fig. 331.
The base-board should be fastened to the ground to prevent the recoil from displacing the ballista at every shot. Two screw-eyes are screwed in the base-board. The trigger is fastened to the end of the base-plank C. To the end of the bat-stick fasten a check-string; allow the other end of the string to pass through a screw-eye a short distance back of the trigger, thence to a rude cleat made by driving two nails slanting into the base-plank (as may be seen in Fig. 331), where the end of the string is to be made fast to the cleat.
To the short end of the bat-stick fasten a weight: a sand-bag, a flat-iron, a dumb-bell, or anything heavy, and now your ballista is ready for war. But you have no ammunition ! Stones and rocks are out of the question, as the serious consequences that almost certainly would follow the use of such missiles would deter any self-respecting, law-abiding boy from using them, and if the boy is malicious and fond of cruel tricks the certainty of detection in this case will prevent such a use of the baby ballista, which was invented solely for fun-loving boys. The baby ballista throws shells that burst with a cloud of smoke, and it would do no injury to a boy if a bomb burst on his head.
The Shells.
These are made of tissue, or thin, light paper, flour, and dough. Place some flour in the paper, then a piece of dough to give it weight, then some more flour; gather the corners of the paper and twist them together like a big paper torpedo; reinforce the twist with a piece of thread or string, and the shell is complete. Elevate the front of the ballista by placing some object under it, boards or stones, fasten the other end securely, with the check-string draw back the bat and fasten it back with the trigger.
Place a shell in the chamber, pull the trip-string, and bang! your flour bomb is hurled through the air at great speed, and when it strikes a hard object the paper bursts, and a cloud of flour flies out just as smoke does from a gunpowder shell.
By a few experiments the range can be very accurately measured, so that it is possible to strike repeatedly the same spot, or very near it. This is done by shortening the check-string and marking the length with a knot at the screw-eye. Now load and fire, and mark the spot where the bomb bursts, let out some more check-line, make another trial and mark the length with a knot, thus a knotted check-string will mark just where the shells will reach, and you can always reach the point you wish by letting out or winding up the check-line to the proper knot.
The foregoing description is intended for an engine to work in the city. In the country it is often possible to find two young trees of green growing wood that will answer for the uprights A and B. Out in the woods or fields you may shoot with almost any object without endangering life or limb.
