40 AQUATIC MICROSCOPY FOR BEGINNERS. 



one end to pass arOund the upper part of the eye-piece, 

 and the Other to be bent into a handle like a small 

 hollow square. Cut another strip 

 about one inch long and one- 

 fourth inch wide, and double it 

 length-wise so that it will still be 

 an inch long, but only one-eighth 

 of an inch broad. Take one of 

 the small brass hinges to be 

 T,. • -o a . , had for a cent, ■ solder one end 



Fig. 5. — Reflector for ' 



Drawing the Magni- to the holIow handle and the 

 ■'^"' other to the narrow doubled 



strip; into this narrow piece place a thin-glass square, 

 the thinner the better, and the instrument is done. 

 To use it, turn the microscope horizontal, have a 

 faint light on the object and a strong one oh the 

 paper, bend the strip of brass around the upper part 

 of the eye-piece so it will not slip, the hollow handle 

 and hinge being directed toward the table, and move 

 the hinge until the thin cover is placed obliquely in 

 front of the eye-glass of the eye-piece. -Look down 

 through the glass square toward the paper on the 

 table, and the image of the object on the stage will 

 seem to be thrown on the white surface, where it can 

 be traced with a pencil. The image is really reflected 

 from the surface of the thin square, and the pencil is 

 seen through it, but the eye unconsciously combines 

 the two so that both are seen together. The secret 

 of success here is a faint light on the object, a 

 strong one on the paper, and a thin glass square. A 

 long sharp pencil-point is also an advantage. . 



A micrometer is for measuring objects under the 

 microscope. It is made by ruling a number of short 



