^0 The Microscope. 



and I have little doubt that 'under his leadership we shall make 

 great way yet. Dr. Simpson, the President, also possesses much 

 influence. He is Health-Officer here, and has in that capacity, both 

 before and since he took up the duties of his ofiice, attracted atten- 

 tion not only in England, but on the Continent. He is a capital 

 microscopist, and imbued with no end of energy in the interests of 

 our society." We feel sure that the Calcutta Microscopical Society 

 will exert a positive influence on Indian science, and we wish it the 

 success which it deserves and is sure to win. 



We desire to call attention to the valuable articles on the 

 spectroscope and its application to medical practice, commenced in 

 our last number. We are giving rather more space to this contri- 

 bution than is our custom, but we feel sure that our readers will 

 appreciate Dr. Waterman's careful consideration of this important 

 subject, and although many other articles are crowded over to another 

 month, in consequence of the space occupied, we so rarely have an 

 opportunity to publish anything on spectroscopy from so distin- 

 guished a source, that we feel sure the omission of other matters will 

 be gladly ignored. 



Acknowledgments. — From Wm. J. Morgan, Somerville, Mass., 

 photo- micrographs of formation on lobster bone; from Rev. J. D. 

 King, Edgartown, Mass., mounts of black-oak stem, bugula flavella, 

 sponge, sycotypus cannaliculatus; from E. S. Coutant, mount of 

 female long- scale insect. 



TECHNOLOGY. 



Mater's Carmine. — This staining-fluid (Am. Natwalist), pre- 

 viously described as " alcohol carmine," is a modification of Gren- 

 acher's acid carmine. 



Carmine 4 grams. 



Water 15 c. cm. 



Hydro-chloric acid 30 drops. 



Alcohol (8 ^) 95 c. cm. 



Ammonia (enough to neutralize). 

 The pulverized carmine is mixed with the water and the acid, 

 and dissolved by boiling; the alcohol is then added, and the solution 

 neutralized by stirring in ammonia until a precipitate begins to 

 appear. This method of procedure is safer than the one hitherto 

 followed, according to which the carmine was dissolved by boiling in 

 the alcohol plus the acid. 



