1898] MICROSCOPICAL JOURNAL 25 



oughly with 95 per cent, alcohol until the collodion around 

 the section appears colorless, and clear with a clearing 

 fluid, preferably clove oil. The tissue will be well de- 

 fined and the bacteria will stand out deeply stained against 

 the more lightly stained cells of the tissue. — From R, C. 

 Reed's paper read at Toledo, 1897. 



Gates' Double Microscope. 



A writer in the English Mechanic claims to have seen, 

 years ago, the effects reported by Mr. Gage and to have 

 proved them all illusions. He says that setting up two 

 microscopes as claimed results in enormously increasing 

 the spherical and chromatic aberation and in the produc- 

 tion of false images. The two objectives are never apian- 

 atic and usually uncorrected. Then diffraction may 

 cause apparent detail to appear in an image which is not 

 actually in the object. It is therefore believed that 

 Grates has been deceived by this scheme. 



It is said that Gates shows ignorance of fundamental 

 principles when he speaks of "a lens of small aperture 

 like a l-16th" not equaling a l-6th for his purpose as if 

 the amount of light utilized by any objective depended 

 simply on the size of the opening as is the case with tele- 

 scopes. That the cone of light admitted by the objec- 

 tive has an influence does not appear to have been con- 

 sidered by him. 



PRACTICAL SUGGESTIONS. 



By L. a. WILLSON, 

 cleveland, ohio. 



Ptlidium CILIare. — The name of this beautiful specimen 

 sometimes gets printed as Palladium ciliare. The spel- 

 ling is peculiar and emphasizes the fact that scientitic 

 names should be plainly written. Much blame upon the 



