BLOOD. GLANDS. LYMPHATICs

ment by ammonium sulphide, or by dilute alcohol (3 to 4
parts water and 1 of absolute alcohol). 6. Osmic acid, I to
t Wj   1 per cent. 7. Ammonia-carmine. 8. Hematoxylin. The
Z       neutral (single) chromate of ammonia is used in 5 per cent
solution; chromic acid in 1 to 30,000.
597. Endothelium of Lymph-spaces of the Eye.'-Schwalbe
recommends treatment for half a minute with 1; per cent.
t   silver solution.
In an excursus on the silver-method, Schwalbe concludes,
after reviewing the evidence, that the silver is reduced in a
longt layer of liquid that exists in the superficial furrows between
I      contiguous cells; the black lines thus formed are a true pre-
M   cipitate, and this kind of stain must be distinguished from
her the other reaction in which by exposing tissues for some time
to the action of more concentrated solutions, there is formed
a combination of the inter-cellular cement-substance with the
an      silver, that turns brown on exposure to light.
J for     598. Lymphatics of Skin, Gold- and Silver-method (the
fy oggans' method 2).-A piece of skin having been stretched on
nid the authors' histological rings3 (see description of the appa-
ratus, 1. c., also 'Journ. Roy. Mic. Soc.,' vol. ii, p. 357), the
1he   hypodermis is treated for 30 seconds with a per cent. solution
of silver nitrate, then washed with water and treated for 30
's     seconds with a - per cent. solution of gold chloride; then
an  washed with water and exposed for a short time to diffused
di     daylight.   Treat with glycerin (whilst still on the rings),
ad      remove the hair (and epidermis if possible), and mount in
P! 14 glycerin. Avoid acetic acid.
599. Lymphatics of Bladder, Gold- and Silver-method (the
1 Ibid., vi (1870), p. 5.
2 Robin's 'Journ. de 1'Anatomie,' &c., 1879, p. 54.
3 The Hoggans' histological rings are supplied by Burge and Warren,
42, Kirby Street, Hatton Garden, E.C., at 10s. per dozen pairs, prepaid
(1 inch inside diameter).

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