THe MICROSCOPE. 1% 
spring is slipped over it to keep it from bending too short. This tube 
reaches about an inch below the bottom of the inner tube, and serves 
as a siphon to draw off the surplus water. It is self-acting, starting 
when the hole in the funnel reaches the level of the highest part of 
the bend in the siphon ; it continues to act until the level of the 
water reaches the bottom of the mside tube. If a cork is pressed 
tightly in the funnel, the bottle can be carried in any position with- 
out danger of leaking, while sufficient air will be admitted through 
the siphon to keep the contents sweet. 
Nikrtrorow’s Carmine.—Dr. Nikiforow (Zeit. f. Wiss. Mik.) 
recommends a formula for a carmine stain which acts intensely on 
the nucleus, and can be used with advantage for staining specimens 
in toto, and which does not require after treatment with the strong ~ 
acids which act harmfully on the tissues. It is prepared as follows: 
Take 3 parts of carmine, 5 parts of borax and 100 parts of water, 
and boil in a porcelain dish until a small portion of the carmine has 
dissolved. Add _ sufficient ammonia to dissolve the remaining 
carmine, and the liquid takes on a deep cherry-red color. The 
mixture is now evaporated by boiling to somewhat more than one- 
half its volume. Carefully neutralize with dilute acetic acid, when 
the cherry-red color gives place to one of a carmine tint. The 
secret is not to get too much acid (Grenacher’s carmine), for such a 
preparation will require after treatment with an acid. The safest 
way is to add the acid slowly and experiment from time to time. 
When the solution is prepared, a few drops of carbolic acid may be 
added, and it will keep indefinitely. Tissues which have been 
preserved in alcohol are stained by it in about fifteen minutes, 
though no overstaining takes place after twenty-four hours. 
AuconoLic SoLturion or Hamaroxyiin.—Dr. G. Cucatti (Cen- 
tral b. f. Bakter. u. parasitenk.) gives the following formula for 
making a hematoxylin solution which possesses the advantages of 
never turning bad and of staining only the chromatic part of the 
nuclei, the color being fixed most deeply in the karyokinetic figures. 
Dissolve 25 grm. of pure potassium iodide in 25 cem. of 
distilled water .and pour, the mixture into a glass-stoppered bottle 
containing 75 cem. absolute alcohol, shaking the whole repeatedly. 
Then grind together in a mortar 75 ¢.grm. of hematoxylin crystals 
and 6 grm. of alum. When these are intimately mixed, add 3 ccm. 
of the iodide solution. Keeping the mixture well stirred, add little 
by little the rest of the solution, and then pour into a well-stop- 
