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THE GUIDE TO NATURE. 



THE HOMEMADE TELESCOPE. 



focus of one and one-half inches and 

 one inch in diameter ; the other with a 

 force of half an inch and half an inch 

 in diameter. Get a tube about one and 

 one-half inches long" which fits into 

 the focusing tube and glue thick strips 

 of paper in each end, in such a way that 

 the lenses will be exactly colliniated. 

 They should have the plane sides toward 

 the eye and the small lens should be 

 nearer the eye. Place them one inch 

 apart, arranging a diaphragm as shown 

 in (a) Fig. 3. This is a Huyghenian 

 eyepiece and can be purchased, already 

 made, for about one dollar and a half. 

 It is well to have several eyepieces of 

 different power; the one described will 

 magnify sixty-four diameters if the ob- 

 ject glass of the telescope is forty-eight 

 inches. 



Strips of canvas should be glued on 

 the whole of the large tube and over the 

 cap, bending down the ends and gluing 

 them for about one inch inside the cap. 



A coat of paint can be applied ; the in- 

 side of all the tubes should be painted 

 a dead black. A tin bucket top, the 

 proper size, makes a satisfactory cover- 

 ing for the lens cap when the telescope 

 is not in use. 



In making the stand we should select 

 the strongest material that can be found 

 about the house. Strips from an old 

 oak bedstead will make a strong tripod, 

 if securely put together. 



Two wooden pieces (a) Fig 4, two 

 inches wide, fourteen inches long and 

 three-fourths of an inch thick, are at- 

 tached to the ends of an oak block which 

 is two inches square on the ends, and 

 three inches long ( 1: ) Fig. 4. A bolt, 

 five and one-fourth inches long, hav- 

 ing a fixed head on one end and a thread 

 on the other, passes through the center 

 of the ends of the three-inch block (c) 

 Fig. 4. A nut screws on the threaded 

 end to hold the pieces tightly to each 

 end of the block, but allows them to 



