( 568 ) 

 PROCEEDINGS OF THE SOCIETY. 



Meeting of 8th April, 1885, at King's College, Strand, W.C, 

 THE President (the Eev. Dr. Dallinger, F.R.S.) in the 

 Chair. 

 The Min'tp? of the mcciiiig of 11th March last were road and 



con finned, and were signed by tho President. 



The List of Donations (exclusive of exchanges and reprints) 

 received since the last meeting was submitted, and tho thanks of the 

 Society given to tho donors. 



Slides (6) of Diatoms (Stcphanodiscus Niatjarw'), showing From 



filameutmis projections My. 11. Mills. 



Lee, A. B., Tlie Mierotoniist'a Vade-mecum, pp. vii. and 424. 



8vo, London, 1885 The Author. 



Slides (1:5) of Mentzelia Flvridana, Sulanum verb iscifolium, and a 

 Fuiisns from an uccuuut-book which bad been in a fire- 

 proof vault for several years Mr. II. ]V. Fuller. 



Mr. Crisp referred to Schicck's Kevolver Microscope exhibited in 

 December 1883,* in ^vhich a drum revolved beneath the objective 

 ■with the objects arranged on the periphery, so that by turning that 

 drum they were brought successively into view. The novelty of that 

 Microscope Mas challenged, and one on a similar principle was pro- 

 duced, made nearly sixty years earlier by T. "Winter, which was 

 considered to be the earliest of all such forms.f It now appeared, 

 however, that the latter had been anticij)ated by one made two centuries 

 a<TO. This was proved by a description and illustration of tho 

 instrument which ajipearcd in an old Italian book, without title-page, 

 which, together with a model, was handed round for inspection. 

 The first page commenced, "Nuove Inventioni di tubi ottici dimostrato 

 neir Accademia Fisico-matematica Pomana, I'Anno 1G86 " (svpra, 

 p. 518.) 



Mr. Beck said that an interesting portion of the instrument was 

 the spring which was used for adjusting the focus of the lens, because 

 that was the subject of a patent which had been taken out about 

 fifteen years ago. 



Mr. H. G. Madan exhibited the form of polarizing prism recently 

 suggested by M. Bertrand in the Comptes Keudus,J and also described 

 in the Journal. § He thought it would interest the Fellows, as it was 

 almost the only one which had yet been seen in this country, added 

 to which it was always more interesting to see a thing in the flesh 

 than merely to read a description of it. The principle of the con- 

 struction of this prism was known to Jamiu as long ago as 1869, and 



* Sec this Journal, iv. (1884) p. 112. 



t Ibid., p. 115. 



i Comples Rcuduri, xcix. (1884) pp. 53S-iO. 



§ Vol. iv. (1884) p. 965. 



