216 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



gum requires attention, for if allowed to proceed too far the preparation 

 loses its transparency ; if not sufficient the thin pellicle may be torn by 

 the balsam. 



Circular Slide for Opaque Objects.* — At the December 1913, 

 Meeting a circular revolving slide for opaque objects was exhibited 

 by R. Finlayson. The illustration (fig. 28) shows this ingenious appa- 

 ratus as fixed on the Microscope. A description of the apparatus was 

 given by the inventor. 



Fig. 28. 



Simple Device for obtaining a Moist Ghamber.f — R. Legendre 

 describes this method of making a moist chamber for examining micro- 

 scopical preparations which may be damaged or spoilt by the weight of 

 the cover-glass. A clean rectangular cover-glass is picked up with forceps 

 and the corners successively softened in the by-pass flame of a Bunsen 

 burner. In this way little balls are formed which are of the same size when 

 each of the corners are heated for the same time. A little practice will 

 enable anyone to obtain balls of any desired thickness. Thus prepared, 

 the cover-glass rests on its four corners and prevents the specimens from 

 being unduly pressed on. 



* See this Journal, 1913, pp. 94-5. 



t C.R. Soc. Biol. Paris, lxxvi. (1914) pp. 265-6 (1 fig.). 



