Page:Popular Science Monthly Volume 24.djvu/100

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90
THE POPULAR SCIENCE MONTHLY.

structed for slipping over the eye-piece, so as to preserve the proper distance between the eye and the eye-lens when making observations; and a second similar cap should be made, and furnished with a disk of black or red glass, for protecting the eye when viewing the sun. For myself, I use a disk of thin microscopic glass, smoked and fastened in a cap which slips over the eye-piece.

But a telescope, even such as I have described, and which has a power of only twenty-five or twenty-six diameters, needs a stand, and this can be constructed easily and cheaply of one-inch pine and a few nails and screws, something after the pattern shown in Fig. 4. By laying the telescope on the two end-supports, Y Y', greater steadiness is secured than by using a single support in the center; and the rods y y' are easily raised or lowered, and may be fixed in their positions by the little wedges w w'. The stand is thirty inches high, sixteen inches broad, and twenty-five inches long. The rods y y' are forty inches and sixty inches long respectively. The blocks B B' are built up of pieces of one-inch board, nailed together; then an auger-hole is bored through the whole, so as to form a sheath or tube in which the rods may slide easily, but without so much lateral motion, or "wiggle," as they would have if they only passed through one thickness of board.

By following these directions you will have a really useful achromatic telescope; small, indeed, and insignificant when compared with the six-foot reflector of Lord Rosse, or with one of Clark's twenty-six inch refractors; but, nevertheless, a veritable Jacob's ladder, by which you can ascend—if not into—at least twenty-five twenty-sixths of the way toward heaven; a perpetual source of pleasure, to a family of intelligent children, on moonlight nights and on occasions of eclipses; worth a whole year's "schooling" as an incentive and help to the study of the universe, and a practical realization of an answer to the oft-mouthed prayer—

"Nearer, my God, to thee!"

 
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THE UTILITY OF SCHOOL-RECESSES.
By JOSEPH CARTER.

THERE is a growing tendency to abandon the school-recess. The editor of the Boston "Journal of Education" says of the no-recess experiment, adopted in Rochester, New York, that it has given "perfect satisfaction." Among the advantages gained, he mentions, "a continuous school-session without interruptions in school-work"; "better health of pupils, on account of freedom from exposure to cold and wet weather in the midst of each session"; "discipline easier, on