850 SUMMARY OF CURRENT RESEARCHES RELATING TO 



washed with absolute alcohol. Benzol. Benzol dammar. (If not washed 

 thoroughly the nuclei are blackish instead of red ; if too long, the ground 

 substance is too pale.) The stain was used for the electric organ and 

 embryos of the torpedo. The nuclei of fish-corpuscles are red, the plasma 

 green. 



New Formula for Burrill's Stain.* — Prof. T. J. Burrill finds the fol- 

 lowing formula gives excellent results in staining Bacillus tuberculosis : — 

 Fuchsin (anilin-red), 1 part ; pure carbolic acid 2 • 5 parts ; glycerin (com- 

 mercial) 10 parts. 



The directions for use are as follows : — Add 3 drops of this stain to a 

 drachm (teaspoonful) of distilled or soft water ; float a cover-glass, on which 

 a thin film of sputum hardened by heat has been spread, on the liquid and 

 heat to near boiling ; remove from lamp and let stand two or three minutes ; 

 decolorize in nitric acid (1 part) and water (5 parts) ; wash in water, and 

 examine, or dry and mount in balsam. Contrast stain, if desired, after the 

 first decolorizing, with anilin-blue. 



This formula is much more satisfactory than the previous one, for there 

 is less liability of precipitation of granules on the cover, and the time is 

 greatly shortened. 



In the absence of other apparatus, &c., a cheap tablespoon, with the end 

 of the handle bent down to make a level support, answers excellently well 

 for holding and heating the stand, and nothing can be better for the heating 

 than a common coal-oil lamp, the watch-glass, crucible-cover, spoon, or 

 what not being held above the top of the chimney. This is better, too, for 

 hardening the sputum-film than the flame of a Bunsen burner. 



Prof. Burrill is sure this stain will keep, for there is nothing in it to 

 precipitate by keeping, as so generally occurs with anilin-oil mixtures. 



Staining Elastic Fibres.f— Dr. G. Martinotti fixes and hardens the 

 material with a • 2 per cent, solution of chromic acid. The sections, after 

 having been well washed in water, are placed for forty-eight hours in a 

 solution of safranin (safranin 5 parts, dissolved in absolute alcohol 100 

 parts, to which 200 parts of water are added after a few days). The sections 

 are again washed, dehydrated in spirit, cleared up in oil of cloves, and mounted 

 in balsam. The elastic fibres are stained a deep black, the nuclei are of a 

 bright red colour, and the rest of the specimen is stained diffusely red. The 

 elastic fibres come out quite clear and distinct ; those in arterial walls are 

 especially suited for this method. 



Nerve Staining.! — Dr. J. Pal remarks that Golgi's method causes a 

 precipitate of mercury upon the cells, for if the sublimate pieces are treated 

 with a 1/2-1 per cent, solution of soda sulphide, the staining is more intense, 

 owing to the formation of sulphide of mercury. Such preparations, after 

 being stained with a bright red, give excellent pictures. The author, how- 

 ever, succeeded in staining all the cells by Golgi's method. By the silver 

 method such good pictures are not obtained, and there is more precipitate 

 than occurs from the use of sublimate. As the chromic acid silver salt is 

 soluble in many dyes, it is necessary, if a contrast stain be desired, to change 

 the salt into mercury sulphide by means of soda sulphide. 



Golgi's cell-staining may be used in conjunction with Weigert's hsema- 

 toxylin stain. The sections which have lost, either in the sublimate or silver 

 solutions or in water, their chromic salt, must be placed in a 1/2 per cent, 

 solution of chromic acid for twenty-four hours. Then, without the copper 



* Queen's Micr. Bulletin, iv. (1887) p. 24. 



t Zeitachr. f. Wiss. Mikr., iv. (1887) pp. 31-4. 



X Wien. Med. Jahrb., 1886. Cf. Zeitschr. f. Wiss. Mikr., iv. (1887) pp. 92-6. 



