ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 



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water, cc. 30. This, protected from dust, is exposed to the air 

 till every trace of ammonia has disappeared, when the clear fluid is 

 poured off and the sediment thrown away. 



2. Commercial alcohol, cc. 100 ; pure hydrochloric acid, drops 20. 



3. Concentrated solution of picric acid in distilled water. 



4. No. 2, cc. 15 ; No. 3, cc. 15. 



5. No. 4, with the addition drop by drop of No. 1. Into this a 

 small crystal of thymol is dropped to prevent the growth of mycelium, 

 and the preparation is kept in a stoppered bottle. 



6. Methyl violet, gr. 0*7; absolute alcohol, cc. 10; anilin oil, 

 cc. 4. To this when the colouring matter is completely dissolved 

 is added distilled water, cc. 15. 



The sputum is spread in a uniform but not too thin layer on a 

 cover-glass, and then dried in the air and slightly warmed. It is next 

 placed in a watch-glass with the preparation upwards ; some of No. 6 

 poured on it with an ordinary indiarubber drop-measure, is covered 

 over and left from half an hour to an hour in a temperature of 15° 0. 

 It is then washed in water till the excess of colour is dissipated 

 entirely, when it is put into No. 2 until the preparation is cleared, 

 when it is washed in a fresh quantity of the liquid, and whilst still 

 moist some drops of No. 5 are poured on, and it is left to stand for 

 five minutes. The excess of carmine is removed by draining : it is 

 then washed anew in No. 2, and plunged into distilled water, twice 

 renewed, for eight to ten minutes. The preparation is then dried and 

 mounted in pure balsam. 



When examined under the Microscope the spores appear of an 

 azure-blue inclosed in the transparent envelope of the bacillus, on a 

 rose-coloured ground. 



"When it is desired to colour the whole bacillus instead of the 

 spores alone, the preparation is 

 washed, after being subjected to 

 the action of the carmine, in 

 distilled water without being 

 placed in No. 2. 



Franeotte's Paraffin Filter.* 

 — P. Francotte suggests the 

 apparatus, fig. 83, for readily 

 freeing paraffin that has been 

 used, from the dirt, fragments of 

 sections, &c., which after a time 

 contaminate it. A B is a double 

 funnel with water between the 

 two casings, the inner one termi- 

 nating in a bent tube T. Blotting- 

 paper is placed inside the funnel 

 and a spirit-lamp applied at the 

 bottom. An aperture at u is for 

 supplying water. 



The apparatus will also enable paraffin to be obtained at any 



* Bull. Soc. Belg, Mier., xi. (1885) pp. 79-82 (1 pi.). 



a thermometer and one at u' for 



