A panta-graph is a simple mechanical linkage for enlarging, copying or reducing the size of a picture. It is shown in Fig. 51.

To make one of these instruments get four strips of wood about 1/8 inch thick, 1/2 an inch wide, and 18 or 20 inches long. Now drill 1/16 inch holes 1/4 inch apart in each stick the whole length of it. In the ends of three of the sticks make a hole the size of a lead pencil.

Fig. 50c. How To Draw An Ellipse With A Thread

Fig. 51. How A Pantagraph Is Made And Used

Make two tin tubes each 1/2 an inch long and fit them into the holes in the ends of the sticks and push a bit of pencil through each tube; screw a block of wood 1/2 an inch thick to your drawing board and screw one end of another stick to the block and the sticks together with screw eyes.

Now tack a sheet of paper under the pencil in the free end of the stick and a picture under the pencil in the jointed ends of the sticks, then trace the picture with the latter, and the other pencil will make an enlargement of the picture. By changing the position of the sticks a picture can be copied or reduced in the same way. A pantagraph can be bought for as little as 25 cents or for as much as $125.00.39

39 A pantagraph can be bought of any dealer in art supplies or drawing materials.

Fig. 52. how a reflecting drawing board is made and used