82 JOURNAL OF THE [July, 



cord. This arrangement gives very easy, uniform motion, and 

 avoids all unequal strain upon the fine adjustment. 



Meeting of March 17TH, 1893. 



The Vice-President, Dr. Edw. G. Love, in the chair. 



Twenty-six persons present. 



Mr. Frederick Kato was elected a resident member of the 

 Society. 



Dr. Arthur Mead Edwards read a paper entitled "On Mount- 

 ing Objects in Substances of High Refractive Index." Dr. 

 Edwards also donated specimens of Gum Thus to the Cabinet 

 and for distribution. 



OBJECTS EXHIBITED. 



1. Brass slips for diffusing heat in mounting : by Arthur 

 Mead Edwards. 



2. A super-stage for elevating the object above the stage of 

 the microscope, allowing very oblique light from beneath : by 

 Arthur Mead Edwards. 



3. Inexpensive slides of diatoms, prepared by P. Klavsen : by 

 Arthur Mead Edwards. 



4. Samples of purified Gum Thus, Styrax extracted by xylol, 

 and of Iodide of Methyl : by H. G. Piffard. 



5. Diatoms mounted in Styrax : by H. G. Piffard. 



6. Human skin undergoing calcification : by H. G. Piffard. 



7. Pleurosigma Genus Platte, 70 forms, mounted in mono- 

 bromide of naphthalin : by Henry C. Bennett. 



In reply to the question by Dr. F. D. Skeel, "Can diatoms be 

 stained ? " Dr. H. G. Piffard replied in the affirmative, referring 

 to the accounts by M. Tempere, of Paris. Dr. Skeel stated that 

 agate can be stained by successive immersions in honey and 

 sulphuric acid> and that many carnelians and agates are thus 

 stained. 



Rev. J. L. Zabriskie gave some points of his experience on 

 the ease and rapidity of mounting in glycerin. In case of ob- 

 jects coot of an inch or less in thickness, permanent glycerin 



