200 
DLVIII.—CANAIGRE. 
(Rumex hymenosepalus, Torr.) 
The history of this new tanning material was given in two previous 
articles in hod Kew Bulletin (1890, pp. 63-69, and 1894, pp. 167—168). 
re was given in 1895 in the Botanical Magazine (t. 7433). 
Keesing t to the following extract from the Report for 1896 on the 
Trade and Agriculture of California (Foreign Office 1897, Annal No. 
1922), it is rapidly making its way as a tanning material for light leather. 
* Canaigre is the American corruption of the Spanish ** cana agria," 
sour cane, It is also called ** Yerba-Colorado” in Mexico, localisms 
being “red dock” “tanner’s dock," and “wild rhubarb.” The best 
way to Propagate the plant is by use of small roots rather than by seed. 
About 1,000 Ibs. of tubers will plant an acre, and October and November 
are the best months for putting in the crop, though where irrigation can 
be practised, planting may be done at any time. The value of canaigre 
as a tanning agent, either alone or in connexion with e tannins, has 
been proved beyond question. For light leather it gives great tensile 
hemlock. It isa quick tanner, and the yellow colour absorbed by the 
hide in the process of tanning is considered highly desirable for certain 
leathers. The sliced and dried tubers, containing an average of 30 per 
cent. of tannic acid, are worth from 8. to 9l. per ton. A yield of from 
seven to 10 tons per acre would give 24 to 31 tons of the dried cone 
for which there is a constant demand in Europe and America, [nas 
as the plant grows wild in this vieinity, and the seed roots are mee 
obtained, the industry commends itself to the farmer of l means, as 
it is harvested in such a short period after planting." 
DLIX.—EXTRACTION OF GUTTA PERCHA FROM 
LEA 3 
The following communication supplements the information already 
given in the Kew Bulletin (1891, pp. 231-239). 
Extract from letter from Director * Gardens and Forest Depart- 
ment, Straits Settlements, to Roya — Kew, dated Botanic 
Gardens, — (— 18, 18 
The leaves are imported in sacks dry from Borneo and Johore. Most 
of the trees are overcut in Singapore, and there are no more leaves left, 
I hear. The leaves and twigs cost four dollars and a half a picul 
(189 lbs.) They are then put, damped with hot water, into a rolling 
machine, tw orking against each other, which grind them to 
pow vid. The powder is thrown into tanks of water and shaken about. 
'The gutta floats in the form of a green mealy-looking stuff, is lifted out 
by fine copper T nets, € in warm water m: pressed into moulds. 
m the leaves, and the 
] do not know how long it will last, on account of the difficulty of 
procuring leaves, which must, I think, sooner or E stop the trade.” 
