202 THE MICROSCOPICAL NEWS. 
ment at 30 or 40 degrees from the horizontal. Dry in the air or 
with moderate heat ; then pass the glass through a flame somewhat 
quickly three or four times, holding the smeared surface up, and 
from a bottle, through the cork of which passes a glass rod, put 
on a drop of the glycerine violet ; after one minute or less wash 
with water by means of a stream from a wash-bottle, and mount 
while wet for examination, the upper surface being wiped dry. If 
for permanent preservation, see that the cover glass and stained 
material is thoroughly dry ; then mount directly in pure balsam, or, 
better in some respects, but not so good in others, in Farrant’s 
solution of gum and glycerine. All this can be done without 
putting the object out of hand, and in a very short time,.and our 
specimen remains fit for the cabinet or for re-examinations, months 
and probably years afterward. The use of an alcoholic solution of 
blue or red aniline would, with the same or similar treatment, be a 
complete failure, the whole surface, glass and all, remaining smeared 
with the dye in spite of water washing, and the whole colour dis- 
appearing with the use of alcohol. With other organisms, as, for 
instance, the micrococcus of pear blight, the aqueous solutions of 
red or violet aniline are partially successful, while methylene blue 
entirely fails, but the strong glycerine solutions of the two former 
give far better results. 
A method of “fixing” aniline colours, devised, I believe, by 
H. A. Reevis, of England, has been tried by myself with success- 
ful results, though sufficient time has not elapsed to prove the 
durability of the stain. Alcohol does not remove it. The stained 
material, whether section of tissue or dried film on the cover glass, 
is first treated with a saturated aqueous solution of tannin and dis- 
tilled water in equal parts, to which is added a little carbolic acid, 
for three to five minutes ; then, after washing in water, submit to a 
strong aqueous solution of potassio-tartrate of antimony (tartar 
emetic) for an equal time, and after thorough washing in water 
transfer to alcohol, a clearing oil, and balsam. I have tried a num- 
ber of processes for staining Baczllus tuberculosis, the now well- 
known organism of pulmonary consumption ; but have succeeded 
only with the use of aniline oil and fuchsin in alcohol and water, as 
recommended by Ehrlich and others. In one instance only a good 
stain, apparently, resulted from this red aniline with aniline oil in 
glycerine ; but I could not repeat the accomplishment, possibly, 
however, from the want of fresh material though with that tried the 
Ehrlich process succeeded. Dr. Gradle, of Chicago, succeeds 
with a saturated alcoholic solution of fuchsin in five to eight times 
the quantity of a 5 per cent. aqueous solution of carbolic acid. I 
have tried the same mixture without success, but my proportion of 
carbolic acid was considerably greater. Gibbes, of England, makes 
a distinction between fuchsin and magenta, but no such difference 
