THE MICROSCOPE. 



What shall we commence with? Here are some lovely little 

 seeds, it may be of the portulaca, or the common chickenseed. 

 Finding their diameter to be a little less than the thickness of 

 our blotting pad, we will determine to make our cell of the latter, 

 and so proceed to stamp a hole in a portion thereof with our ys in. 

 punch, after which we cut out a square of J/s in., leaving the hole 

 in the center. Before attaching this cell to the glass slip a dead 

 black bottom must be make for it, and this is best done by pasting 

 a strip of the thin black paper upon the slide. And here let me say 

 that the best and most satisfactory paste for this and all subsequent 

 processes I have ever used is made with ordinary wheat starch, 

 boiled, and beaten to the consistency of thick cream. It adheres 

 tenaciously to glass, wood or paper and seems to have no tendency 

 whatever to absorb moisture from the surrounding atmosphere. 



The black paper having been pasted upon the slide, the cell is 

 in its turn to be pasted upon the paper so that its centre shall be 

 percisely in the center of the slide, when a weight should be placed 

 upon it until dry, and finally attached. The seeds may be attached 

 to the bottom of the cell by means of shellac cement, or liquid glue. 

 Still better and in every way satisfactory is a cement made by dis- 

 solving a small quantity of shred gelatine in cold water, gently heat- 

 ing it after being dissolved. This should be made in small quanti- 

 ties as wanted, since it will not keep. It is tough and very tenacious, 

 and does not dry too quickly, excellent qualities in a cement for 

 such purposes. Use only a sufficient quantity to attach the speci- 

 men firmly; any superfluity makes an unsightly blotch in the mount. 

 The cleansed glass cover is now to be cemented on, with the same 

 paste, when we are ready for the finishing. 



The best colors for the covering papers are a bright canary for 

 the back, and a red with gold bronze figures for the front, and 

 these are the kind usually found on sale at the opticians.* The 

 back should be pasted on the under side of the glass slip and 

 turn up over the sides and ends on to the upper side of the same, 

 over which it should extend for an eighth of an inch all around. 

 Then the red and gold front with a fs in. hole previously punched 

 in its centre is to be pasted smoothly over the whole, equi-dis- 

 tant from the edges all around. The labels, — usually plain white 



* The writer regrets that the illustrations intended for this article have not been fin- 

 ished by the engraver in season to appear with the letter press. 



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