24.0 SUMMARY OF CURRENT RESEARCHES. 



(6) Miscellaneous. 



Biological Laboratory Methods.* — P. IT. Mell's text-book, though 

 specially intended for the use of students in biological laboratories, will 

 be found extremely serviceable by workers with the Microscope in other 

 branches of science. Its scope is highly practical and the information 

 is conveyed in clear and simple language. The first three chapters 

 deal with the Microscope, eye-pieces, objectives, and accessory apparatus. 

 Then follow four chapters on the methods necessary for transforming 

 a piece of soft tissue into its permanent condition of a stained and 

 mounted section. 



Much space is devoted to photomicrography, the apparatus and 

 processes being described in considerable detail. 



The last chapters deal with the apparatus and methods requisite for 

 bacteriology, bleaching, decalcification, injection and maceration, the 

 polarisation of light and its application to biological investigations ; 

 the work concluding with a copious supply of useful formula} and 

 tables, and an appendix on the arrangement of the laboratory and its 

 furniture. 



The volume is well got up, is of convenient size, and the illustrations 

 are clear and frequent. 



Counting the Red Corpuscles of the Blood.f — C. A. MacMunn 

 showed at the meeting of the Physiological Society on January 17, 

 lantern slides illustrating how the counting of the red corpuscles can 

 be done by photographing fresh films. The blood is diluted to half or 

 to 1 p.c. in the Thoma-Zeiss bremocytometer. Not only are the red 

 corpuscles seen on the plate but also the rulings of the cell-slide. The 

 most suitable power was found to be a f in. objective and a Zeiss eye- 

 piece No. 4, with a G-in. tube-length. This method enables a per- 

 manent record of blood-counts to be kept, and also to make the 

 enumeration at any time. Of course, the Microscope and camera are 

 used in the vertical position. 



/ Fusible Metal Stopper for Test-tubes.* — F. Glage recommends 

 " fusible metal " for sealing up test-tubes as they are cleaner than resin 

 or paraffin. The alloy melts on boiling water and when heated over the 

 flame drops off like sealing-wax. If dropped on to a glass plate thin 

 disks, about the size of a shilling, are formed. These disks are easily 

 manipulated, and by the aid of a little heat made to fit over the mouth 

 of test-tubes with great accuracy. 



Gbe villus, A. Y. — Keimapparat zur Erhaltung konstanter Feuchtigkeit im 

 Keimbette wahrend einer beliebig langen Zeit. 



Belli. Bot. CentraM., Orig.-Arb., XII. (1902) pp. 283-92 (1 fig.). 

 K AC sen, 0. — Neuerungen auf dem Gebiete der Desinfektion nnd Sterilisation. 



Centralbl. Baht., I' 8 Abt. Kef., XXXII. (1903) Nos. 24 and 25. 



* Macmillan & Co., London and New York, 1902, xii. and 321 pp. and 128 figs. 



t Nature, Ixvii. (1903) p. 327. 



% Centralbl. Bakt.. 1" Abt. Orig., xssiii. (1903) p. 479. 



