( 45 ) 

 NOTES AND MEMOKANDA. 



No Meeting of the Royal Microscopical Society this Month. — 

 We beg to notice that, contrary to what has already appeared, there 

 will be no meeting of the Royal Microscopical Society this month. 

 It was intended to have held one, but the College being occupied on 

 both the first and second Wednesdays in the month, the Council has 

 been compelled to give way. Consequently, Fellows will observe that 

 there will be no meeting of the Society held this month. 



Contributions to the Journal. — We may state that various papers 

 remain on hand. Among others, a long French communication, 

 which cannot appear this month. We mention this fact to allay any 

 anxiety which may be felt by persons who send contributions which 

 do not immediately ajipear. We do our utmost in all cases to insert 

 the articles which are sent to us, as well as the Eeports of the local 

 Societies ; but of course cases occur wherein even for two or more 

 numbers paj)ers do not ajjjJear. We mention this fact merely to re- 

 assure oiu" correspondents as to their communications. 



COKKESPONDENCE. 



ToLLEs' Steeeoscopic Binocular Eye -piece. 



To the Editor of the * Monthly Microscopical Journal.^ 



HoBART College, Geneva, N.Y., U.S. 

 Sir, — I wish to correct as widely as possible a statement in regard 

 to the stereoscopic binocular eye-piece, which attributes the invention 

 to me instead of Mr. Tolles, to whom really the whole credit belongs. 

 Dr. Carpenter* has made, unintentionally, such a statement, and it has 

 been copied by others.! I doubt not it will be rectified in future 

 editions. This misstatement was unknown to me until within a few 

 weeks. If it had been known I should have made the correction 

 promptly. It is not diflicult, perhaps, to account for the mistake, 

 inasmuch as I first exhibited this eye-piece in England at the soirees 

 of the Microscoiiical Society and the Royal Society, and to nrunerous 

 individuals, among them Dr. Carj)enter himself, who expressed his 

 satisfaction at its performance. Mr. Ladd, the well-known philo- 

 sophical instrument maker, 11 and 12, Beak Street, Regent Street, 

 had it for some time in his possession, and indeed made one, which 

 however was much inferior to Mr. Tolles', as Mr. Ladd had not time 

 to determine the proper curves, if indeed the lenses were achromatics 



* 'Microscope,' 4tli ed , p. .S5. t ' Tlie Microscope,' by .J. Hogg, 7th ed., p. 119. 



