91 
DXLIV.—TENGAH BARK. 
The species of the small natural group of Mangroves form one of the 
most characteristic features of the muddy tidal estuaries of the tropics. 
Rhizophora, jar typical eem is found in c" the old and the new 
world; the others are confined to the form 
e Kew Bulletin for 1892 ob. 227232) contained a full account 
of an attempt to introduce West Indian Mangrove bark into European 
commerce as a tanning material. 
The present corr espondence g gives the available information respecting 
one of the East Indian Mangrov es, Ceriops candolleana, which appear 
to be attracting some attention. 
DIRECTOR, QARCENS AND Forest DEPARTMENT, STRAITS 
SETTLEMENTS, to ROYAL GARDENS, Kew 
Singapore, 
Dear Mar. Tuatserton-Dyer, November 8, 1892. 
nding you a small box of extract of Tengah bark 
(Ceriops candolleana). This bark is used here for tanning, and also 
for dyeing, especially in vie Las ien with Indigo. The bark was cut 
up in bits and boiled for two hours in a copper pan, and the liquid 
eventually dried by € 
In dyeing, it is sed to give a brownish red colour to ven e 
especially to get er black and purple. The cloth is firs t dye 
engah, dried, and then dipped in Indigo, and comes out Nes = 
black according to the strength used. 
The tree is very common here and used as firewood, and the bark 
mostly wasted. So it could be prepared at no great cost. I should be 
pe if you would get an opinion on it either as either a dye or a tan. 
pits extracts have, I believe, been tried wating but have not 
between the species, but all kinds of barks ave tbe stewed up 
together and the result tried. Now, 1am going to work through all 
the Mangrove tan barks one by one, and try if we cannot make some 
use of them. 
Yours, &c. 
` (Signed) Henry N. RIDLEY. 
Nore by the PROFESSOR OF DYEING, YORKSHIRE COLLEGE, LEEDS. 
“Tengah” bark extract behaves, as aati its dyeing properties, 
in a similar manner to a good quality of Cat 
When used along with Indigo, as is vereint the "eges the latter 
is probably applied in a * copperas" (ferrous sulphate) vat; in which 
case the ** Tengah " will combine with the iron and mme A as indieated 
cie a grey colour, which in conjunction with the Indigo blue gives 
the b 
Tengal extract would certainly be of value to dyers. 
(Signed) J. J. HuwMzr. 
February 8, 1893. 
