106 The Microscope. 



minuteness and beauty. A remarkable feature in the preparation 

 was the perfect success with which the fine network of capillar}" 

 vessels was injected with the cannine. 



The president said an interesting subject for microscopical 

 investigation by the members would be the reason why popcorn pops, 

 while other kinds do not. Chemists claim that it is on account of 

 the greater (quantity of oil contained in the popcorn becoming 

 volatilized by the heat, and he would like to have the matter looked 

 into from the microscopical point of view. 



A specimen of the Kieselguhr was exhibited by Professor Ash- 

 burner, and found very rich in diatoms. 



A. H. Beeckenfeld, Secretary. 



ELEMENTARY DEPARTMENT. 



I 



SECOND LESSON. 



" CLEANLIXESS IS AKIN TO GODLINESS." 



NSTRUMENTS and reagents required : 1. Two needle holders. 



2. A few slides and cover-glasses. 3. One ounce of pure 

 glycerin. 4. A 1 per cent, solution of sodium chloride. 5. Four 

 ounces of distilled water. 6. One ounce of sulphuric ether. 7. One 

 ounce of acetic acid. 



1. Two pen-holders will serve as well as anything else for 

 grasping the needles, which latter should be of medimn size, with 

 good point, and inserted, eye-end, to about ^ of their length in the 

 holders. It would be well to have several of these holders fitted with 

 needles of assorted sizes. If a more elegant instniment is desired, 

 a few like these 



in the accompanying cut, kindly furnished us by Bausch and Lomb, 

 of Rochester, N. Y., can be secured. They cost about 15 cents each. 

 Not more than one of the curved needles is needed, indeed, they are 

 not at all indispensable for fine work. 



2. Slides should be 8x1 inch in size, ground- edged and of 

 medium quality. The chance-crown variety, though containing oc- 

 casional flaws, is quite good enough. Round cover-glasses, ^ to ^ 

 inch in diameter and tolerably thick. The thinner ones are, of 

 course, more desirable, but are so fragile that the beginner will do 

 well to let them alone until more experienced in handling the thicker 

 ones. 



