1893.] MICROSCOPICAL JOURNAL. 265 



Microscopical Test for Beeswax. — Make :i solution of the 

 suspected wax in chloroform, and let a drop of it fall on a slip. 

 As soon as a i)ellicle begins to form let a cover-glass fall on it, 

 but do not pre-s down, at least not heavily. Put in a cool i)lace 

 and let stand. In the course of from twent}^ to thirty minutes 

 you may examine it, using a one-fifth objective and two incli 

 eye-piece, and if the wax is free from mineral fats, or from fatty 

 acids, you will observe tufts of feathery crystals form in such 

 manner that each group assumes the shape of dumb-bells, or 

 double balls of cr3'stals, radiating from a common center in each 

 ball. 



These balls vary from 25 to 50 microns (1-1250 to 1-625 

 inch) in diameter, according to the rapidity of evaporation of 

 the solvent. The crystals are the same for yellow or white wax, 

 and in pure wax no other shapes are seen. If animal, vegetable, 

 or mineral fats are present, the wax crystals will be seen inter- 

 mingl d with the characteristic crystals of the adulterating fats. 

 The observation can be made without the use of the polariscope, 

 but the latter renders the detection of foreign fat much easier. — 

 National Druggist. 



BACTERIOLOGY. 



Incoagulable Albumen — a new culture medium. — M. E. 

 Marchal has devised an albuminous solution, with which he 

 has successfully cultivated a large number of bacteria, both 

 pathogenic and saprophytic. The solution is prepared as fol . 

 lows : — The white of fresh eggs is diluted in distilled water and 

 filtered. A solution of 1-1.000 of iron sulphate is then added to 

 the albumenous liquid in the following quantities : — 



Albumenous solution, 1 to 5 per cent, 1 to 5 cc. per litre. 

 5 "10 " " 5 "10 " " " 

 « " 10 "15 '• " 10 "15 " " " 



The iron sulphate has the curious property of preventing the 

 congulation of the albumen by heat. The liquids cin be steri- 

 lised at once in an oven at 115.° The medium thus prepared is 

 perfectly limpid, its reaction being slightly alkaline. M. Mar- 

 chal finds that this solution is very easily and rapidly prepared, 

 and it also advantageously replaces the ordinary bouillons in 

 use. — Bull. Soc. Beige Micros. 





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