6o THE MICROSCOPE. 



blood, and their destruction was never observed by Bizzozero, pro- 

 vided the blood was mixed with a saline solution. Again, the time 

 at which coagulation sets in, corresponds very closely to the time 

 that these new corpuscles undergo degeneration. The fluids which 

 retard or prevent coagulation — as, solutions of carbonate of soda 

 and sulphate of magnesia — have the same action in preventing the 

 granular degeneration of these corpuscles. The indifferent solution 

 of salt does not preserve them, but one to which the methyl-violet 

 has been added does. 



From this evidence Lt appears as highly probable that the 

 formation of fibrine takes place, under the direct mfluence of these 

 corpuscles. To them Bizzozero gives the name of "Blutplattchen." 

 — Cincinuati Medical News. 



Resistance of Seeds to Extreme Cold. — E. Wartmann has 

 exposed fresh gathered Spanish chestnuts for nearly two hours to a 

 cold of at least no", derived from a mixture of sulphuric ether and 

 solid carbonic acid, each seed being carefully wrapped in thin tin- 

 foil, so as to prevent the surface coming in contact with the ether. 

 The chestnuts were then planted in the soil; they germinated and 

 developed in every respect as successfully as those which had not 

 been exposed to the cold. The power of resistance to extreme cold 

 appears, indeed, to be a very general property of seeds. — Arch. Sci. 

 F/iys. et A- at. 



Tracings on Glass for the Lantern. — The following 

 method, by Mr. George Smith, appears to be satisfactory: A piece 

 of- finely ground glass is rubbed over with a trace of glycerine, in 

 order to make it as transparent as possible. It is now easy to write 

 or draw on the prepared surface with a hard and finely pointed 

 black lead pencil, and the glass is so transparent that the finest de- 

 tails of any engraving over which it may be placed can be seen 

 quite distincily. The drawing having been finished, the plate is 

 washed with water, in order to remove the glycerine, aud dried. A 

 thin coat of Canada balsam or of negative varnish now serves to 

 render the slide permanently transparent and ready for the lantern. 

 — Scientific American. 



