ZOOLOaY AND BOTANY, MICK08C0PY, ETC. 693 



Invention of the Binocular Microscope. — Some controversy has 

 recently taken place in America * on this subject, having been opened 

 by a paper from Colonel J. J. Woodward, in which he complained 

 that the claim of Dr. J. L. Eiddell, Professor of Chemistry in the 

 University of Louisiana, to be the inventor of the binocular Micro- 

 scope had not been properly recognized in England. 



It appeared, however, that Colonel Woodward in writing his paper 

 had, by some strange accident, overlooked the fact f that both Mr. 

 Stephenson and Mr. Wenham had publicly acknowledged Professor 

 Eiddell's priority, J and it may be added that the original papers of 

 the latter were duly published in this country at the time.§ 



Colonel Woodward also objects to Dr. Carpenter having given to 

 MM. Nachet credit which really belongs to Professor Eiddell in 

 regard to the form of binocular Microscope introduced by that firm, 

 as to which, however, Mr. Wenham points out that M. Nachet's modi- 

 fication was a notable improvement and real advance upon Eiddell's 

 original idea. 



We do not believe that any one in this country would venture to 

 dispute the right of Professor Eiddell to the title of " Father " of the 

 binocular IVIicroscope. Certainly, as the references given in the 

 previous foot-note show, those who have subseq[uently so successfully 

 improved upon Eiddell's original ideas have never attempted to 

 do so. 



At the same time it is only fair to recall the fact that if the bino- 

 cular Microscope had not advanced beyond the point at which Eiddell 

 left it, the use of the instrument would be very limited, and where 

 now there are 100 binoculars to be foimd there would not then have 

 been one. 



Priority of Invention. — There is getting to be more and more 

 of a tendency in modern times for authors or inventors who 

 have at some period or other dealt with a given subject, to 

 attempt to claim for themselves the credit of any modifications or 

 improvements which may have been subsec[uently made by others, 

 even although those improvements may for the first time convert an 

 impracticable idea into a workable one. This has even been carried 

 to such a point that suggestions which the authors themselves origi- 

 nally condemned and discarded as useless in practice have been again 

 claimed, when it was subsequently shown (from another point of view) 

 that they could be made available. 



The question of oil immersion itself is a leading example of 

 this, for although the use of oil was suggested at the same time as 

 water, it was discarded in practice as not presenting any advantages, 

 wholly and entirely through want of the knowledge that the apertures 

 of oil or water immersion objectives exceed the maximum of dry 



* Amer. M. Micr. Journ., i. (1880) pp. 221-30 (2 figs.) ; ii. (1881) p. 29. 

 Amer. Journ. Micr., vi. (1881) pp. 14-15. 



t Amer. M. Micr. Journ., ii. (1881) pp. 29-30 (Mr. Stephenson's reply). 

 Amer. Journ. Micr., v. (1881) pp. 26-7 (Mr. Wenhara's reply). 



X Mon. Micr. Journ., x. (1873) p. 41. 



§ See Quart. Journ. Micr. Sci., i. (1853) pp. 236, 304 ; ii. (1854) p. 18. 



