I. MICROSCOPES. 783 



3653. Sliding Tray, carrying microscope lamp and Hartnack 

 microscope, for demonstrating objects to a class. 



W. R. M'Nab, M.D. 



This tray runs on two rollers partly covered with india-rubber, thus 

 destroying vibration, and permitting the tray to be used on an ordinary 

 table. 



3654. Mica-plates for preserving botanical and anatomical 

 preparations. (See Mineralogy.) Max. Raphael, Breslau. 



Mica-plates are conveniently employed for preserving hygroscopic ana- 

 tomical preparations, such as of foliacious mosses (" Laubmoosen "), &c. 

 For this purpose, the mica is split halfway through, and the preparation placed, 

 in a moist condition, between the plates, which close of their own account 

 owing to the elastic nature of the mica. 



Should the preparations be required for examination, the plates have only 

 to be dipped for a second or two into water ; they may thus serve for years 

 for repeated microscopic examination. It is obvious that covering plates of 

 mica may be used for all botanical microsopic purposes. 



3654a. New adjusting and self-centering Shadbolt's 

 Turn-table for making microscopic cells. 



Harvey, Reynolds, and Co. 



3655. Knife for microscopic sections by Dr. Gower. 



T. Hawksley. 



3656. Knife for microscopic sections by Dr. Madox. 



T. Hawksley. 



3656a. Dr. Klein's Section Knife. T. Hawksley. 



3657. Moist Chamber. T. Hawksley. 



3658. Series of Glass Canulae, and Nozzle dissecting 



Instruments. T. Haivksley. 



3659. Three Diaphragms for microscope. Laurent. 

 3659a. Diaphragms (4), various. Laurent, Paris. 



3660. Microscope Stand, medium size (stand No. 1 in the 

 exhibitor's catalogue), with rack and pinion for the coarse adjust- 

 ment, and with rotation round a vertical as well as horizontal axis, 

 with five eye-pieces, and Abbe's illuminating apparatus. In a case. 



C. Zeiss, Jena. 



3661. A Set of Objectives, from 30 millimetres to 1 milli- 

 metre focal distance, in all 21 pieces. Some with the correction 

 for cover glass. The whole in case with lock and glass lid. 



C. Zeiss, Jena. 



This collection embraces a complete set of microscope objectives, as contained 

 in the catalogue of the exhibitor No. 21, 1874. Some of them are furnished 

 with an " adapter," so as to suit the length of the tube of English microscopes. 

 The threads are those of the " Society's screw." 



