458 
pound; the weight is kept fairly constant by diluting the latex 
before boi iling and regulating the amount of diluted latex for each 
biscuit (Thompson, Rep. on Visit to Mani Reserve, 1911, p. 
Coagulation of the latex by evaporation and absorption was t 
one time common. cavity was cut in the trunk of a tree and 
milk was thrown in daily until it was full; the milk is then covered 
with palm leaves and kept air-tight, if possible, and in 14 days or 
a month it becomes solid; in the rainy season it might take two 
months to solidify. This was known as the “silk rubber”? (see 
Kew Bull. 1895, pp. 248, 245). 
Under the heating pronos which is upay adopted because of 
the greater convenience, it is recommended to let the fresh latex 
Benin City Communal Pl. 1910, p. 5). In Uganda the milk 
stands for a couple of days in large earthenware pots before boiling 
(Kew Bull. 1907, p. 188). Formalin or absolute alcohol have been 
found effective in coagulating cold Funtumia latex, but Purub (a 
German patent preparation of fluorine) and acetic acid have no 
effect (see Kew Bull. 1911, p. 126; Ann. Rep. For. and Agric. 
Depart. Lagos, 1910 (for 1909), p. d 
- There are some very good samples in the Kew Museum made 
s "boiling" the latex (Gold Coast, 1911), ‘ biscuits?” or 
= sheets ds coagulated naturally in a wooden receptacle (Aburi, 
1911), * 'erepe," and *'lump " coagulated with the juice of the 
“ Diecha"' Vine (Strophanthus Preussii) (Evans, Gold Coast, 
1909) ; rubber coagulated by an infusion of the leaves of Bauhinia 
reticulata (Evans, Gold Coast, 1908), with Formol (Gold Coast, 
1911) and by double-pot process, afterwards passed through a 
small hand machine (Evans, Aburi, 1910). 
Mixing the rubber with sand, stones, or rubbish of any descrip- 
tion, latices of terior quality, all of which were formerly too 
common, has been met in Nigeria by the ‘‘ Adulteration of Pro- 
duce Ordinance.” 
The tree 1s usually tapped in the rainy season about May to 
October. The yield may vary considerably in each = according 
to age, etc., and for each locality, As from 1-4 oz. from trees 
i b 
tr 
known (Kew Bull. 1895, p. 242 2 but as history has proved the 
trees did not last long at ‘ins rate. Some very fair tests have been 
made (1910) in the Benin City Communal Plantations (see 
Thompson and Foster, Rep. l.c.) in which the results show an 
rubber. A slightly higher yield of 1:59 oz. per tree in the same 
pue was obtained in 1911—20,210 trees yielding 1885 lbs. 
11 oz. of dry rubber (Col. Rep. Ann. No. 735, 1912, p. 13). The 
average o field of latex at each tapping is given as about one quart 
m each tree, which may amount to one pound of rubber per 
