ZOOLOGY AND BOTANY, MICKOSCOPY, ETC. 597 



projecting for about 6 in., is now to be firmly lashed to a light 

 cane or stick, and the apparatus is complete. 



In order to use the apparatus, move it gently backwards and 

 forwards on the surface of the water, under the surface, or just above 

 the bottom of the pond, and among the weeds ; the muslin will allow 

 the water to pass through it, whilst any living organisms will be 

 retained by the bottle. This can from time to time be examined with 



Fig. 117. 



a pocket lens, and when it is found to contain anything, the lower 

 ring of wire can be slipped off, and the neck of the bottle pushed up 

 through the upper ring, inverting the net. The contents may thus 

 be poured off into another bottle, and after rearranging the apparatus, 

 fishing may go on again. The object of the piece of wire connecting 

 the two ends of the net is to keep all stiff, so that the bottle can be 

 turned in any direction, and yet both the upper and lower mouths of 

 the net will remain open. 



Preparations of Coal.* — P. F, Eeinsch's preparations of coal from 

 the carboniferous strata, the Dyas and Trias (the material being very 

 difficult to reduce to thin and sufficiently transparent sections), are 

 made by using the finest emery employed in polishing mirrors. 

 Powdered chalk obtained by levigation, and carbonate of lime preci- 

 pitated from lime-water by soda, are also used. A small piece of cork 

 serves as a rubber. During the process the preparation is moistened 

 with glycerine. 



Cathcart's Ether Mierotome.f — C. W. Cathcart's object in 

 venturing to add another to the many forms of freezing microtome 

 was : — (1) to obtain a simple ether spray-producer which would not 

 allow any ether to escape unevaporated ; (2) to have an efficient 

 microtome for use with the ether spray, which would be so simple 

 in its mechanism as to admit of manufacture and production at a 

 comparatively low cost. The microtome can be sold at 17s. 6d., 

 including the spray-producer, and it freezes l-4th in. of tissue 

 in 1^ or 2 minutes, using in the process about 2 drachms of ether, 

 which cost something less than a farthing. 



The instrument is thus described by the author : — " The spray- 

 producer works on the same^^principle as the scent sprays which have 



* Bull. Soc. Belg. Micr., ix. (1883) pp. 87-8. 



t Journ. Anat. and Physiol., xvii. (1883) pp. 401-3 (2 figs.). 



