1893.] MICROSCOPICAL JOURNAL. 321 



merely turn the wheel until you get the condenser in place; one 

 turn more, and you have a dark field ; one turn more, and the 

 polorizer is in position, and you have then merely to clap on 

 the eye-piece the tourmaline, which latter is to be rotatated. It 

 is ver}'^ eas}' of management. 



A word about tourmalines, — the price, about $8.00, is out- 

 rageous. Get a light-colored tourmaline from any dealer in 

 minerals (Standish, Maine, appears to be the place where such 

 tourmahnes are to be found). A piece about half an inch 

 square of varying thickness (at times half an inch thick) will 

 cost about 20 cents, and must be ground down. Cleavage there 

 is none, and it is not brittle. The bluish-colored ones are stated 

 to be the worst, polarizing very little, and the brown ones 

 good, best the nearly white ones, which however appear to be 

 rare." 



A nice view of the Microscope fitted up by Mr. Wilder is 

 given in the frontispiece of the present number. 



MICROSCOPICAL MANIPULATION. 



Sealing-Wax Cement. — Make a saturated solution by ex- 

 posing an excess of sealing wax in alcohol for several days. 

 Shake the bottle occasionally. This is strictly a varnish and 

 not a cement. 



To Cement Ebonite Cells to Glass. — Use a thick solution 

 of shellac in spirits of wine. For glass or mental cells, marine 

 glue is sufficient. The interstices may be filled and the joint 

 rendered air-tight by gold size. 



Method of Staining Spores. — The following method is con- 

 tributed by Philip Jaisohn, M. D., assistant professor of Pathol- 

 ogy and demonstrator of Histology in the Medical Department 

 of Columbian University, Washington, D. C. 



The Moller's method of staining spores generally gives a fairly 

 good result but a modification, which I have made, produces 

 more brilliant contrast, viz : clean a glass slip in equal parts of 

 sulphuric acid and alcohol ; wash it again, in water, (running 

 spigot preferred); wipe off the water with a dry towel; put a 

 large drop of sterilized water on the slip with a pipette and pass 

 through a flame (Bunsen burner or spirit lg,mp) a few times, 



