154 PATHOGENIC BACTERIA. 
(2) Wash in water. 
(z) Contrast-stain in saturated aqueous solution 
of methylene-blue. or in Loffler’s blue for one-half 
minute. 
(7) Wash in water, dry, and mount. 
(2) Examine with the 7, inch oil-immersion 
lens. The bacteria should be red in a blue field.! 
(2) Koch-Ehrlich Method. 
(a) Stain cover-glass preparations in anilin fuch- 
sin or anilin gentian-violet for twelve to twenty- 
four hours. 
(4) Decolorize for three to five seconds in 20 per 
cent. nitric acid. 
(c) Wash in water, in 60 per cent. alcohol for five 
to ten seconds, and again in water. 
(2) Contrast-stain in aqueous methylene-blue for 
one minute. 
(e) Wash, dry, and mount. 
(3) Gabbet’s Method. 
(a) Stain in steaming Ziehl’s carbol-fuchsin for 
one minute. 
(2) Wash in water for two to three seconds. 
(c) Stain in Gabbet’s blue? for thirty seconds or 
longer. 
(2) Wash in water, dry, and mount. 
(4) Rosenberger’s Method. 
(a) Stain in carbol-fuchsin (cold) for five to ten 
minutes. 
(4) Without washing stain for one to two minutes 
1For the detection of tubercle bacteria in sputum when 
present in very small numbers see page 157. 
2 See Appendix, page 172. 
