1884-85.] EdinhurgJi Naturalists Field Club. 261 



knife slides in the usual manner. Tlie knife is not shown in the 

 fig-ure. The microtome shown in fig. 2 is designed for objects 

 which are imbedded in paraffin or other medium previous to cut- 

 ting. The instrument consists of the usual cylinder, piston, and 



Fig. 2. 



screw — the novel point in its construction being, that the upper 

 part on which the section-knife slides is provided with glass rails 

 similar to those used in the Cathcart microtome, and that the 

 instrument is made to be fixed to the table by a separate clamp, 

 and not by means of a screw whicli presses one part of the micro- 

 tome from the other when binding it to its support. 



At the third meeting (9th January 1885) a lecture was delivered 

 by Mr A. N. MacAlpine, B.Sc, on " Tlie Woody Tissue of Plants: 

 its Arrangement in Root, Stem, and Leaf, and its Detection" — the 

 lecture being illustrated by the lantern. At the fourth meeting 

 (5th February 1885) Mr Alexander Frazer drew the attention of 

 members to the construction of Brooke's double nose-piece for the 

 microscope, and explained the adjustment of the same ; while Mr 

 A. D. Richardson gave a demonstration on double-staining, which 

 was much appreciated by the members, and furnished matter for 

 some discussion. At the fifth meeting (6th March 1885) a further 

 explanation of double-staining, with an exhibition of double-stained 

 objects, was made by Messrs Richardson and Henderson ; while Dr 

 Macfarlane made a communication on "Recent Advances in the 

 History of Cell-Formation." The sixth and concluding meeting 

 (6th April 1885) was occupied by a demonstration on Photo- 

 Micrography, by Mr William Forgan. The following is Mr 

 Forgan's explanation of the process : — 



PHOTO-MICROGRAPHY. 



The term Photo-micrography means the production of enlarged 

 photographic pictures of microscopic objects by means of a micro- 



