( ^4 ) 

 NOTES AND MEMOKANDA. 



Examining the Blood-globules. — Our readers will remember tbat 

 some time ago there was an important discussion in these paees 

 between Dr. Woodward and Dr. Richardson relative to the possi- 

 bility of distinguishing the blood-globules of man from those of 

 other mammalia with sufficient accuracy to determine points in 

 medical jurisprudence. Now Dr. Richardson sends us a micro- 

 photograph on which the blood of man and the pig are represented 

 beside each other, and asks us whether they are not quite distinct. 

 We answer, in the present instance they are perfectly distinct not 

 only in size but in form, but we question whether this is always the 

 case. However, the specimen is of interest. 



An Improved Form of Cox's Turn-table. — We learn from the 

 ' American Naturalist' for December 1875, that Miller Bros, of New 

 York have made an improved form of this excellent contrivance, 

 which is marked by its handsome iron stand and its careful adjust- 

 ment of the centering movements. " If," says the ' A. N.,' " the 

 real convenience of this table were known, its use would soon become 

 general." 



COERESPONDENCE. 



Hebr Hasert's Objectives: a Eeply to F.E.M.S. 



To the Editor of the ^Monthly Microscopical Jotirnal.^ 



Eisenach, January 9, 1876. 



Dear Sir, — Fair play, if you please. Having been rather wantonly 

 attacked by some man in your .J ournal, I hope you will give my reply 

 a place in your columns. The report given by Mr. Hickie is cer- 

 tainly a statement of facts, after careful investigation, while the abuse 

 of the Fellow R.M.S. seems to have no other foundation but ill-will. 

 How much credit Dr. Dippel deserves, the following will show to all 

 who interest themselves for truth. In two letters of Dr. Dippel, in 

 my possession, dated 1861, 4/5 and 7/7, he says, " your objectives 

 resolve in direct light from a north window. No. III. the XII., and 

 No. II. the XX. group of Nobert's scale most distinctly ;" in the 

 second letter he says, " used with the achromatic condenser, both 

 systems give very sharply defined images excellently suited for the 

 most subtle anatomical investigations." 



How much Dr. Dippel has since perfected himself in disregarding 

 facts, I do not know, not having seen his edition since 1872 ; but in 

 his first edition you will find sufficient contradictions regarding my 

 lenses, if you will compare pages 119 with 143 and 169, where he 

 gives my lenses in one place the highest resolving jjowers for diatoms, 



