1892.] MICEOSCOPICAL JOURNAL. 147 



96 per cent, methyl alcohol 10 parts 



Salt water 90 " 



Natrium chloride i';, "• 



He places the specimen in a glass jar (2x1 inch) filled with 

 water. Then add the solution, putting in one drop per minute; 

 if not retracted after 45 minutes, pour on quickly some hot sub- 

 limate ; in this way some specimens are secured half-retracted. 

 To preserve specimens for sections put them in i per cent, os- 

 mic acid (for 2 minutes), and then successively in 5, 10, 20, 30 

 per cent, alcohol up to 90 per cent. ; harden in absolute alcohol 

 and imbed in paratfine ; stain with borax-carmine and haema- 

 toxvlin. 



BIOLOGICAL NOTES. 



Teaching with the Microscope. — Professor Leviston well 

 says that the teacher who attempts physiology without a micro- 

 scope is to be blamed for leaving his pupils in the dark about the 

 most vital principles ; that botany without illustrations of cell 

 growth is a mere fiat study ; and that a child six years old may 

 begin to use a simple microscope as a plaything. 



Weed Extermination. — Moses Craig, of the Oregon Agri- 

 cultural Experiment Station, has issued a bulletu^ containing 

 pictures and descriptions of the common weeds of Oregon, with 

 practical directions for destroying such weeds. This is an ex- 

 cellent illustration of the good which farmers ai'e now getting out 

 of biology. Send to Corvallis, Oreg., for a free copy. 



Effects of Electrocution. — After the execution of Kemler 

 it was thought that certain changes had been produced by elec- 

 tricity in the cells of the body, but since the more perfect use of 

 this mode of execution the most complete study of the micro- 

 scopic appearances indicates that none of the tissues are appre- 

 ciably injured by the shock. The lethal current of from 5 to 7 

 amperes, with voltage of 1,500, destroys life, but mutilates not a 

 single cell. 



How Sealskin is Prepared. — If we look at a lady's seal-skin 

 jacket, we at once observe its rich brown color, and the velvety 

 softness and denseness of the fine hairs composing it. If this be 

 compared with the coarse, hard, or salted dry seal-skin as im- 

 ported, or, still better, with the coat of the living fur seals, one is 

 struck with the vast difference between them, and wonders how 

 the coarse or oily-looking, close-pressed hair of the live animal 

 can ever be transformed into the rich and costly garment above 

 spoken of. Passing our finger among the hairs of the cat or dog, 

 we may notice short fine hairs at the roots of the longer, coarser, 

 general covering of the animal. This is the so-called under-fur. 

 It equally obtains in most of the land as in the aquatic carnivora. 



