Take the other piece of beech and fasten a rod or roller of wood, two feet and a half long and one inch diameter, into the hole, so that one end is flush with the top side of the wood ([Fig. 6]). Now fasten two uprights to the top, letting them into the wood ([Fig. 6]). These are to be three-quarters of an inch thick, and four and a half inches high, and are to be three and a half inches apart.
Fig. 7.
Bore a hole in each upright about half an inch from the top and about one quarter of an inch in diameter. Now get nine screw stair-eyes at the ironmonger’s, and about seven feet of brass wire one eighth of an inch thick. Get this wire straightened. Into the inside of each leg, and one foot from the top, screw one of the brass stair-screws. Now get a piece of wood, circular, three inches diameter and one and a half inches thick (a ribbon roller will do very well), and bore a hole right through the centre, one and a quarter inches in diameter. Round this piece of wood at equal distances screw three more of the screw-eyes. Now cut from your brass wire three lengths of fourteen inches, and turn a ring at each end of each piece, and hook one end of each piece into a screw-eye in the circular block, and the other end into the eye in each leg, closing up the rings so that they will not come unhooked. This arrangement will keep the top from tilting. Now the stand is finished, and we will take the tube in hand if it is quite dry and hard. Before drawing out the roller, cut the ends off quite square with a sharp knife, leaving the tube thirty-seven and a half inches long. Now draw out the roller without breaking the tube. We must next fix the object-glass. Cut a strip of cardboard half an inch wide, and long enough to go all round inside the tube without lapping, and to fit tightly. Push this inside, so that it will form a shelf half an inch inside the end of the tube. Glue this in its place. Upon this place the object-glass, and fix it there by gluing a strip of cardboard all round inside the tube on the top of the lens. To fix the eyepiece, cut from the roller used to make the tube on, a piece one inch long, and bore a hole right through the centre of it the exact size of the eyepiece tube. Glue this block in the other end of tube. Push the brass tube in this hole with the field-lens inwards. The telescope can be focussed by pushing in or drawing out the brass tube. Get a piece of deal eight inches long and three and a half inches wide and two inches deep. Cut a groove along the top as [Fig. 7], one inch deep and a little more than two and a quarter inches wide, to fit the outside of the tube. Glue this block on the tube, so that one end is thirteen inches from the front end of the tube (the eyepiece end). Put the block in its place between the uprights on the stand, and fix it there by two screws passing through the holes in the uprights and screwing into the block. Pass the rod attached to the uprights through the hole in the top of stand and through the hole in the block underneath.
Fig. 8.
Now we have only to make the arrangement for elevating the telescope. For this you will want the rest of the brass wire and the remaining three stair-eyes as well as two pieces of thin brass plate, four and a half inches long, half an inch wide, and one-sixteenth of an inch thick. Bend these pieces of plate as in [Fig. 8], making the bent parts one inch long, and get the ends cut as in the figure, and have holes drilled in the bent parts a little larger than the brass wire. Cut your wire into two lengths of eighteen and a half inches, and take them to the tinman and get him to cut a screw-thread nearly the whole length of each, leaving about two inches to each. At this end of each get him to turn a ring, and get him to close these two rings into one of the screw-eyes. Get him to make a screw-nut for each wire about the size of a farthing, but about twice the thickness. Screw the eye carrying these wires through the tube into the eyepiece block, screw the remaining two screw-eyes into two of the legs of the stand, on the outside of each leg and about one foot from the top of each. Bend the cut part of the brass plates into rings and close them in these screw-eyes. Now put the screw-nuts in their places in the brass plates, and put the screw wires through the holes in the top, and turn the nuts to the left, which will draw down the wires and with them the eyepiece of the telescope. To turn the telescope to the left turn the right-hand nut to the right, and the other to the left, and to turn it to the right reverse the action of the nuts. In making this telescope you must be very careful in fixing the lenses. They are to be placed so that the centres are to be in one straight line, which line is to be at right angles to the lenses. You can cover your tube with coloured paper to give it a finish. It will be advantageous, in using the instrument, by keeping out all light not wanted, to make a cardboard tube about six inches long and large enough to slide easily on the end over the object-glass and to project about five inches. The telescope is now finished, and will with ordinary care last for years.
Fig. 9.
Appearance of the Moon as seen through one of these telescopes on June 9th