208 THE AMERICAN MONTHLY [Nov 



obtain a specimen which is perfectly straig-ht and round. 

 Sectioning Bolitic Grains.— Lay a g-lass slip on a metal 

 plate and place it over a spirit lamp. Soften a drop of 

 nearly dried balsam upon it with heat, and lay a small 

 plate of mica on it so that it will become cemented to the 

 glass. Upon the mica surface imbed in balsam and ar- 

 range the small objects of which sections are desired. 

 When the balsam is cold and firm the glass is used as a 

 handle by which to hold the objects whilst grinding. A 

 flat surface may be given them as they lie in the balsam, 

 by rubbing with a hone. Heat the glass to release the 

 mica by softening the lower film of balsam, lift the mica 

 with forceps and turn it over on another glass which has 

 been provided with balsam. The ground glass is now 

 downwards, and the other side may be ground as desired. 

 — Science Gossip. 



MISCELLANEOUS. 



Slides. — Geological specimens nicely mounted $2.25 per 

 dozen. Address: Micro., 34 Trederweh road, Dalston, 

 N. E. London, England. 



For Sale. — Fatty Ills and their Masquerades, By 

 Ephraim Cutter, M. D. LL. D., and J. A. Cutter, B. Sc, 

 M. D. $L0O. Box 494, 120 Broadway, New York. 



Personal. — F. K. Twining, Fresno, Cal., makes bac- 

 teriological investigations for the medical profession and 

 others. 



Desirable.^ — Mason, 69 Park road, Clapham, London 

 offers two new sets lantern slides photographed from 

 nature and especially fitted for public exhibition, 38 slides 

 in each ; packed in box for $8.50 each set ; 18 slides illus- 

 trating anatomy of honey bee $4.25 ; 9 slides anatomy of 

 blowfly $2.10. He sends a sample slide for 30 cents post 

 paid, or 18 misceallaneous specimens for 25 cents each. He 

 has stem sections to illustrate distinct orders of plants, 

 sections of cell contents, also reproduction. These with 

 12 special exhibition slides for $2.75 post free. 



