44 THE MICROSCOPE. March 



biologists. The proof that many diseases are caused by bacteria 

 was obtained by vivisection. It consisted in inoculating ani- 

 mals with the specific microbe in question to the exclusion of 

 all others and noting that the animals took the disease and of- 

 ten died of it. Among the results of knowledge gained in this 

 manner it may be remembered that the prevention of cholera 

 has been made more certain and that great numbers of patients 

 especially children have been saved by the anti-toxine treat- 

 ment of diphtheria. Every child thus saved owes it not merely 

 to medicine but to biolog}^ and to the microscope ; not only 

 to the vivisections of Klebs, Loeffler^ Koch and Pasteur but to 

 .he old lens-i)olisher of Delft. 



Liverpool Meeting. — The British Association for the Ad- 

 vancement of Science will meet at Liverpool, September 16-23, 

 1896. There will be an excursion to the Isle of Man in order to 

 see the geology of the island. This includes igneous and gla- 

 cial formations and fossil-bearing limestone of carboniferous age. 

 Prehistoric remains are note-worthy. Murine fauna and flora 

 are abundaiit. 



QUESTIONS ANSWERED. 



NoTB. — Dr. S. G. Shanks, of Albany. N. V , kindly rnnsents io receive all sorts of gues- 

 tions relating to microscopy, ivhelke' uslnd l>y pi ufcssionals or avtateurs. Persons o/ tin 

 f ades of experience , from the begi-mer up-,v,ii </, ai f tc Icotne to the benefits of this dep'i>'- 

 nient. The questions are numbered /or Jumre i efereiice. 



237 In the abstract, on the best method of sharpening a microtome 

 knife in the November number of the A. M. M. J., tivo substances are 

 mentioned: Vienna Chalk and Diamantine. Where can I get them 

 and what the cost f T. B. D. 



Diamantine, No. 1. for cutting, small bottles, 25 cents. 

 Vienna Lime, " " 15 " 



For sale by Montgomery & Co., No. 105 Fulton St. N. Y. and 

 probably by any other large concern in the watch tool trade. 



Diamantine is mixed with a little sperm oil but used nearly 

 "dry" on a plane glass surface. No. 1, cuts more freely than No. 

 2. The latter is used for polishing only. 



Vienna Lime is used with water, or better with alcohol, on a 

 plane block tin or box-wood surface. It should be mixed in 



