128 SUMMARY OF CURRENT RESEARCHES RELATING TO 



the curd. The whey is then mixed with 1000 grm. water, 100 grm. 

 gelatin, 10 grm. pepton, and 5 grm. salt, and the solution sterilised for 

 half an hour at 105°. After removal from the autoclave, the solution is 

 filtered through paper into previously sterilised vessels. 



If separated milk is not obtainable, skim milk may be used, but 

 then greater care is required for sterilising. 



Improved Method for Detecting Bacillus typhi abdominalis in 

 Water and other Substances.* — The extensive experience in India of 

 Mr. E. H. Hankin has enabled him to develope a method for isolating 

 typhoid microbes from water and other substances, which appears to be 

 successful in many difficult cases. The procedure is not altogether 

 new, but is rather a modification of methods which have been long in 

 vogue. To give the method in full detail as narrated by the author 

 would require too much space, and it will be sufficient to indicate the 

 essential feature of the modification. The author's experience is that 

 " if tubes containing smaller quantities of Parietti's solution than the 

 maximum permitting growth are chosen, there is a far better chance of 

 isolating the microbe " than if the tube containing the greatest number 

 of drops, and which has become turbid after 24 hours, be selected. It 

 is possible that the method would give better results if the Pasteur- 

 Chamberland filter were used to cencentrate the water. 



Formalin as a Reagent in Blood Studies.f — Mr. E. J. Kizer has 

 found formalin a useful reagent for demonstrating the structure of 

 blood-corpuscles, as it produces no appreciable distortion, does not 

 interfere with staining, and is an excellent preservative. One volume 

 of fresh blood is mixed with three volumes of 2 per cent, formalin, and, 

 after standing for an hour, a drop is pipetted from the sediment to a 

 cover-slip, and, having been spread evenly, the film is allowed to dry by 

 evaporation. The slips are next fixed on the flame, and then dipped 

 once or twice into a 5 per cent, solution of acetic acid. The acid, is 

 removed by water, and the film stained in 2 per cent, gentian-violet 

 solution ; methyl-blue and gentian-violet ; hematoxylin and eosin ;. 

 methyl-green and safranin, or Ehrlich's triple stain. Excess of stain 

 is removed by water or alcohol as the stain requires. Lastly, clove 

 oil or xylol and balsam. 



(3) Cutting', including 1 Imbedding and Microtomes. 



New Delepine Microtome. — This instrument, brought out "by 

 Messrs. E. and J. Beck, was invented by Prof. Delepine some eighteen 

 years ago, and its details have been from time to time perfected and 

 improved by him. It may be used for cutting tissues imbedded in 

 paraffin or in celloidin, and is specially intended for cutting sections 

 of frozen tissues (see p. 126) previously imbedded or not imbedded in 

 celloidin. It claims certain marked advantages over other microtomes, 

 including : — (1) The extreme rigidity both of the razor and of the 

 object ; (2) the unusual strength of its construction, and its durability ; 

 (3) the simplicity and delicacy of the raising motion of the object- 

 holder ; (4) the automatic arrangement for regulating the thickness of" 



* Centralbl. Bakt. u. Par., l le Abt., xxvi. (1899) pp. 554-60. 

 t Proc. Indiana Acad. Sci., 189S, pp. 222-3. j 



