Another and smaller tube, five or six inches in length, and of a size just sufficient to slide easily in the other end of the long tube should now be made. Around the inside of one end paste a band of pasteboard, as in the larger section, but much nearer the edge. When this is dry, paste still another strip inside this one, making a wide edge for the lens to rest against. As this tube is of much greater diameter than the glass, inclose the latter between two disks of cardboard of the same size as the opening in the tube, and each having a round hole cut in its center for the eye to look through. Cover the inner side with paste, and press it against the edges of the strips. Finally, cover the whole thing with some dark-colored paper, pasting it carefully over the surface, and your telescope is completed.
This instrument will present everything in an inverted position, but if the lenses are carefully adjusted, objects at a long distance can be very plainly seen, and a boy can derive a great amount of solid comfort, not only while constructing, but from its subsequent use.
To find the focal distance of a lens, if for any reason the optician does not give it, hold it in the sun, and observe at what distance from itself it makes the smallest point of light. That, if measured, will be its focal distance. The long tube should be from two to three inches shorter than the focal distance of the larger lens.
“What shall we make for Christmas?” is the cry that arises from the children all over this land and abroad, wherever the Christmas season is known and observed; and many a boy would be glad to contribute his share of labor toward making the others of his household happy, if he only could think of something to make. In the following pages, I purpose to give a few directions for some simple things, which boys of ordinary ability can easily execute.
Procure a large, perfectly white, hen’s egg, and after making a hole slightly larger than a pea in either end, blow the contents into a bowl placed to receive it. Paint some little thing on both sides of the shell—a bunch of forget-me-nots or pansies are very good subjects—or, if well acquainted with the brush, a small landscape, inclosed in an oval, is still prettier. After the painting is perfectly dry, varnish it with a brush filled with “retouching varnish,” and, with a long hair-pin, draw a piece of blue or pink ribbon through the holes, and get some lady friend, who can keep the secret, to tie the ends in a pretty bow. A yard of ribbon about an inch wide is required to complete this pretty ornament.