256 SUMMARY OF CURRENT RESEARCHES RELATING TO 



quantity of the foregoing is mixed with water and then stirred with a 

 glass rod dipped in acetic acid. The solution turns bright red. The 

 sections are immersed therein for 1 hour, after which they may be stained 

 with logwood. 



(10) The process may be reversed by first staining with Bohmer's 

 hematoxylin and afterwards with neutral carmin. 



Rapid Method of Iron-Hsematoxylin Staining.* — Dr. A. Gur- 

 witsch has for a long time adopted the following procedure which takes 

 about 10 minutes instead of the usual 36 hours. The sections, stuck 

 on by the water or albumen method, are, after the paraffin has been re- 

 moved and they have been further treated with alcohol and with water, 

 flooded with 2*5 p.c. iron mordant and then placed in the steam of 

 an open water-bath. In this they remain until the mordant begins to 

 bubble or become turbid, when they are washed with water, after which 

 they are treated in a similar way with the hematoxylin solution. 

 Although the sections are usually stained effectually with one application 

 a repetition of the stain may be required. Differentiation is carried 

 out at ordinary temperature. 



New Method of Staining Elastic Tissue.! — Dr. H. F. Harris has 

 discovered that haematein solutions have an affinity for elastic tissue when 

 made in the following way : — hematoxylin • 2 grra., aluminium chloride 

 0*1 grm, 50 p.c. alcohol 100 ccm. Dissolve the hsematoxylin and 

 aluminium chloride and heat to boiling, then add slowly ■ 6 grm. mer- 

 curic oxide. As soon as the mixture turns purple remove from the 

 flame and cool rapidly. The solution is filtered and one drop of hydro- 

 chloric acid added. The solution is then set aside for some weeks in 

 order to ripen. When ripe the stain is used by immersing those sections 

 of tissue in it for 5-10 minutes, then washing for about a minute in a 

 1 p.c. solution of nitric acid in alcohol, after which the sections are 

 cleared and mounted. On account of the close relationship of this stain 

 to Mayer's machaematein the name of elasthsematein is suggested. In 

 connection with the present notice a previous paper by the author may 

 be consulted. | 



Differential Staining for Tubercle and Smegma Bacilli.§ — L. 

 Nencki and T. Podczaski state that smegma and tubercle bacilli may 

 be differentiated by treating the acid-decolorised preparations with 

 alcohol and then contrast-staining with methylen-blue. The smegma 

 bacillus is much less resistant to alcohol than the tubercle bacillus. 



Platinum Method for the Central Nervous System. || — The platinum 

 method, says Dr. W. F. Robertson, consists essentially in placing small 

 pieces of formalin-hardened tissue in a mixture of platinum bichloride 

 (h p.c.) and formalin (5-20 p.c.) for several weeks or months. Sections 

 are cut by the dextrin freezing method, and mounted in balsam in the 

 usual way. A deposit of platinum-black occurs in the tissues, tending 

 specially to take place in certain elements. 



* Zeitschr. wiss. Mikr., xviii. (1902) pp. 291-2. f Tom. cit., pp. 290-1. 



% Cf. this Journal, 1890, p. 049. 



§ Gazeta Lekarska, 1901, No. 45. See Centralbl. Bakt., 1" Abt. Ref., xxxi. 

 (1902) p. 90. || Proc. Scot. Micr. Soc, iii. (1900-1) pp. 122-3 (1 pi.). 



