1896 THE MICROSCOPE. 11 



QUESTIONS ANSWERED. 



NoTB. — Dr. S. G. Shanks, of Albany, N. Y., kiniily consents to receive all sorts of ques- 

 tions relating to tnicroscofiy, ivhethe' askfd l>y />' ofessionals or amateurs. Persons of alt 

 g ades of experience, /rotn the beginner upwaicl, ate lu.lcotne to the benijits <■/ this di/>a>- 

 inent. The questions are numbered for /uiure i e/erence. 



232 Outside of Carpenter^s ivork,ivhich author has the most ex- 

 plicit directions for staining and mounting sections ? — D. E. L. 



Clark's Practical Methods iq Microscopy gives detailed direc- 

 tions for staining and mounting sections. Cole's Methods of 

 Microscopical Research, last (1895) edition, is a very practical 

 work. Gage's book does not give directions for staining sec- 

 tions. 



233 I have a Zeiss Binocular Eyepiece. It was damaged in transit 

 and w is repaired by B. d: L. The left eyepiece does not show the 

 object distinctly, and shows also two margins close together of every 

 object. Is this a necessary result of the double prism, or can it be 

 correct&l .?— D. A. N. 



There are two prisms in the azicd tube beneath the axial eye- 

 piece, which should be very nearly in contact (within 1-2500 

 inch). This less than optical contact causes part of the cone of 

 rays to go to the left. If there is any great separation of the 

 prisms some of the rays will be reflected from the inner "surface'' 

 of the lower prism and some rays will be reflected from first the 

 surface of the upper prism and these two images will not co-in- 

 cide in the left eyepiece. The image in the left or lateral eye- 

 piece should be distinct, but not quite as bright as in the axial 

 or direct eyepiece. 



PRACTICAL SUGGESTIONS. 



By L. a. WILLSON, 

 cleveland, ohio. 



Mushroom Spores. — The agariani or gill bearing 

 fungi are classified according to the color of their spores. To 

 obtain the spores, separate the stem from the pileus or cap, and 

 invert the latter with the gills downward, upon a piece of glass 

 or white writing paper. In the course of an hour or two the 

 spores will be found on the glass or paper. Place a few in a 



