FORMUL/E. 



Wlieu not stated tlie solids are reckoned in grams and the fluids in cubic cen- 

 timeters. Water is understood when no particular soh'ent is mentioned. 



Stains. 



.-Uiiilwlic Soliilioiis of .-Inilin Stains. 

 These should he saturated sokitions, made 

 preferal>Iy with Grubler's staius aud aljsolute al- 

 cohol In wcU-stoppcrcd hottlcs they keep in- 

 dchuitch'. 



(,KXRRAL AND illSCELI.ANKOr.s, 



l-hwiwr's .Inilin C'rntiau I'inlct. 



Anilin oil 2 



Alciihol, 1)5 per cent 5 



Watery Solutiiin.<: nf Anilin Dyes. 



These do not keep long and must be made up 

 fresh each time. If made directl)- from the dr}- 

 pr.wder or crystals, rather than from the alcoholic 

 solution, the resulting fluid should he passed 

 through filter paper before using. Watery solu- 

 tions are usually made by adding the alcoholic 

 solution (o distilled water in any strength de- 

 sired. Usually a few drops of the alcoholic 

 solution to 5 i)r 10 cc. of water is sufficient. 



Anilin Jl'atcr. 



.\nilin w.ater is made by shaking thoroughly 

 one part of anilin in 20 parts of distilled water 

 and filtering it clear liy p.assing one or more 

 limes through filter paper moistened with water. 

 It sliould be prepared fresh each time. .Vnilin, 

 known also as anilin od. is a colorless, oily- 

 l.i(..king fluid. It o.xidizes to a brown color if 

 exposed to the air, and it should therefore be 

 kept in a closc-stoppereil bottle in the dark. 

 The brown fluid is still usable, at least fe.r some 

 purposes. 



Zi eld's 'Caiinil-Piielisin. 



Fuchsin ( basic ) I 



.Absolute alcohf.l 10 



Carbolic acid (5 per cent sol. in 



water ) 100 



The fuchsin should first be dissolved in the 

 alcohol and then the two fluids mixed. .A pow- 

 erful and much-used stain. 



Elirlieh's AnilinAI'uter Gentian I'iolel. 



Alcohidic solution of gentian violet 



( satur.ateil ) .s 



Anilin water 100 



This should be used as s.ion as prepared. It 

 does not keep well. 



Saturated aleoh(,lic (.absolute) sr.lu- 



tic;>n of gentian vii ilet S 



Distilled water ,So 



]\Ii-x well and filler, 



lilirlieli-IJ'eiiiert Anilin Methyl I'iolet. 

 .Alcoholic solution of methyl \-iolet 



( saturated ) 11 



.Absolute alcohol 10 



Anilin water 100 



Does not keep well, 



Anilin I'liehsin. 

 Prepared in the same way ;is Ehrlich's anilin 

 gentian violet. 



Zielil-Nielsmi's Stain. 

 Used chiefly as a means for identifying tuber- 

 culosis. The cei\er-glass bearing the specimen 

 is floated for 3 to 7 minutes on carbol-fuchsin 

 wdiich is heated until steam begins to appe.ir. 

 It is then washed in distilled water, plunged into 

 10 per cent nitric or sulphuric acid long enough 

 to <lecolorize (a very slKirt time). It is then 

 passed through iV) per cent alcohol for a few 

 seconds (just le)ng enough to remo\'e the stain 

 from the backgreiund ), w.ashed thoroughly in 

 water, dried, and mounted in balsam. The 

 cover-glass prejjaration may be obtained also by 

 dropping some ot the stain upon it and liolding 

 it over the flame. This method is more eco- 

 nomical of stain anil time and less muss\' than 

 the preceding. 



I'riettlaeiider's Stain. 



This has been used so far mostly for identify- 

 ing the tubercle organism in sputum. It is 

 made as follows: A few drops of carbol-fuchsin 

 are placed on the prepared co\-er (wdiich has 

 been gently flamed) and healed over a flame 

 until the fluid steams. The cover is then 

 washed in distilled water, and phuii^ed for a half 



1S7 



