COAL-TAR COLOURS IN GENERAL                  113
Commercial name.  Chemical name.  Obtained from-  Literature.
I 16. Bordeaux R  Naphtalinazo-       Ibid.           Ibid.
aus Salz Ri 3naphtoldisulfo-
saure
1 17. Bordeaux G   Same as 16         Ibid.           Ibid.
aus Salz Gi
I 18. Biebricher  p Naphtolazo- Aktiengesellsehaft Bericht d. d. chem.
Scharlach    benzolsulfo-   fir Anilin-   Ges., 1880, 801;
(Ponceau   siurenatrium-  fabrikation in  ibid., 1880, 542.
RRRi)    azobenzolsulfo-     Berlin         803, 980.
saures Natrium
1 19. Orange III Dimethylanilin- Ter Meer u. Co.
(Helianthin, azobenzolsulfo-
Gold-Orange) saures Ammo-
nium
The following are the practical results obtained from
Griesbach's examination :
Anilin yellow.-1. Insoluble in water, soluble in alcohol.
Useless.
" Siuregelb " or " Echtgelb."-2. Soluble in water. Bone
.stains a good orange, cartilage and connective tissue citron-
yellow. Fresh and alcohol preparations stain well, not so
chromic-acid ones. A    nuclear stain, but somewhat diffused
into the plasma. Good differentiation of the different tissues
in a large section, ranging from brightest citron to brown.
Use concentrated solutions, as the stain is considerably washed
out by alcohol.
Chrysoidin.-3. Soluble in water. A diffuse yellow stain;
does not stain bone or any sort of connective tissue; does not
answer with alcohol or chromic-acid preparations.
Bismarck brown (Vesuvin).-4. A nuclear stain, both for
alcohol and chromic-acid preparations; most suitable for uni-
cellular organisms, bacteria, leucocytes, &c. The stain is not
easily washed out by alcohol.
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