686 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
The film thus passes through (1) largin, from 2 to 10 minutes ; (2) 
gallic acid, 2 to 10 minutes ; (3) largin, till clear ; (4) gallic acid again 
if necessary, and so on. 
The cover-glasses should always he burnt on a piece of wire gauze 
to remove all fat. 
By this method clean well-stained preparations can be obtained with 
ease and certainty. 
Staining Intestinal Canal by Van Gieson’s Method.* — Dr. W. 
Moller recommends Van Gieson’s method for staining sections of intes- 
tinal canal. The method was originally intended for the central and 
peripheral nervous system, and consists in staining first with haemato- 
xylin, and afterwards with a mixture of acid fuchsin and picric acid. 
The author adopts the following modified procedure. (1) Stain for half 
an hour in Delafield’s hematoxylin. (2) Immerse in distilled water for 
12-24 hours. (3) Stain for 1/2-1 minute in Van Gieson’s mixture, 
which is composed of 150 ccm. of a saturated aqueous solution of picric 
acid, and 3 ccm. of a saturated aqueous solution of acid fuchsin. (4) Wash 
in distilled water (1/4— 1/2 minute). (5) Dehydrate in 90-96 per cent, 
alcohol (2-5 minutes). (6) Transfer to absolute alcohol for 1 minute. 
(7) Origanum oil; (8) Canada balsam. To the water (4) and the spirit 
(5) must be added a few drops of Van Gieson’s solution to prevent the 
too great extraction of the picric acid. 
The material dealt with had been kept in spirit for years, and the 
sections were “ celloidin-sections.” 
(5) Mounting-, including- Slides, Preservative Fluids, &c. 
New Method for Fixing Paraffin Sections to the Slide.j — Herr K. 
Koninski's gelatin-formalin method is based on the fact that formalin 
renders gelatin firm and insoluble. The slides are covered with a thin 
film of gelatin, after the manner of photographers. When the gelatin 
has set the plate is ready. Upon the dry plate are arranged the ribands 
of sections, and having been smoothed down by the aid of warm water, 
any excess of water is poured off. The plate is then warmed until the 
gelatin is liquefied. The superfluous gelatin is removed with bibulous 
paper, and the plate allowed to dry. When dry it is placed in pure 
formalin for about 10 minutes. Thus fixed the gelatin film holds the 
sections so firmly that the slide may be immersed in boiling water with- 
out fear. 
C6) Miscellaneous. 
Microscopic Detection of Phosphorus-containing Compounds.!— 
Prof. A. B. Macallum discusses the difficulties connected with the micro- 
scopic detection and localisation of compounds containing phosphorus, 
and especially the value of the reducing agents hitherto employed after 
the use of ammonium molybdate for the purpose. He finds that pyro- 
gallol is unreliable, and recommends the use of a recently prepared 
aqueous solution of phenyl by draz in hydrochloride of 1-4 per cent, 
strength. This, in the absence of alcohol or a caustic alkali, gives a 
green colour where phospho-molybdate compounds are present, but only 
* Zeitschr. f. wiss. Mikr., xv. (1898) pp. 172-7. t Tom. cit., pp. 161-3. 
X Proc Roy. Soc. Lond., Ixiii. (1898) pp. 467-74. 
