988 PROCEEDINGS OF THE SOCIETY. 



Mr. F. H. Ward briefly described a microtome designed by him 

 and exhibited to the meeting (see p. 957). Some sections of wood 

 cut with this apparatus were shown under one of the Microscopes on 

 the table. 



Mr. Crisp, in exhibiting Zeiss's travelling Microscope, called atten- 

 tion more particularly to the very light quadrtiple nose-piece and the 

 ingenious arrangement for giving universal movements to the mirror 

 (see p. 955). 



Mr. Beck remarked that the weight of English quadruple nose- 

 pieces was not so much in the nose-piece itself as in the objectives it 

 had to carry. 



Mr. Gilburt made a short communication supplementary to his 

 paper read at the last meeting, the substance of which will be found 

 appended to the paper in a foot note at p. 806. 



Colonel "Woodward's " Note on certain Amplifiers of Zeiss as 

 compared with those of Tolles," was read by Mr. Crisp, and the 

 jAotographs of Amphiplcura pellucida taken by both were laid on the 

 table. The note also contained some remarks on the use of chloride 

 of cadmium as an immersion fluid, especially for micro-photographic 

 purposes, which will be found at p. 943. With regard to Zeiss's y^g-, 

 Colonel Woodward said, " I must add my testimony in favour of the 

 exceedingly satisfactory performance of the new J^ by lamplight, 

 not merely on lined test-objects, which it displays in a more striking 

 manner than even the yV, but especially on such objects as white 

 blood-corpuscles, and similar living tissue elements, bacteria, and the 

 like, for the study of which it appears to me especially suited." 



Dr. R. H. Ward's letter as to the matters to be brought before the 

 National (American) Committee on Micrometry, was read, 



Mr. Beck said it seemed to him that the important practical 

 question which they wanted to determine was whether the scales 

 which they did use were correct. If they had one from Paris, and 

 another from Holland, they would find both of them to be incorrect. 

 Some means was therefore desired by which they could be tested as 

 to correctness. 



Mr. Crisp referred to the paper by Professor Eogers on " Com- 

 parators for Measures of Length," which will be found at p. 947. 



Mr. A. D. Michael pointed out that it seemed doubtful if there 

 was in existence a really true standard metre. 



Mr. Beck said he was not speaking of such minute variations as 

 those which came into considerations of that kind, but of tests as they 

 concerned the practical Microscopist. The question of the absolute 

 length of a metre dealt, he thought, with matters of far greater 

 minuteness than there was any real necessity to take notice of. 



