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Castilian latex can be coagulated or agglutinized also by the 
sand biter, or when placed in a vessel having a fine copper wire 
gauze at its base. The watery fluid drips readily through this 
without allowing the rubber globules to pass, and when all are 
removed the rubber in paste can be turned upon a porous substance 
to dry. With the sand bath, the sand should be fine, clean and 
well wetted. The latex can then be poured upon it after placing 
wire gauze on the surface. These processes, however, do not com- 
pare in cleanliness, nor can so good rubber be made by them, as 
when the readily decomposing albuminoids are washed away by 
creaming process. The rubber produced is also inferior in quality. 
There is every reason to believe therefore that the treatment of 
Castilloa latex with Formalin is likely to become a highly suc- 
cessful method to adopt in the preparation of crude rubber. 
NATURAL INDIGO. 
The following particulars respecting indigo prospects are by the 
Calcutta correspondent of the British Trade Journal : — 
A great deal has been written about indigo during the last few 
months, but the controversy can only tend to convey to the general- 
public an erroneus idea. It has been contended that because the 
. Maharajah of Darlangha turned his estates to the cultivation of 
rhea , that indigo growing has been abandoned in East India; and 
because many consumers have adopted artificial indigo as an experi- 
ment to see how far it can replace the natural product, it is assumed 
that chemical indigo is the more advantageous of the two, and there- 
fore preferred. The argument that the high price of indigo during 
the last Calcutta season again alienated many regular partizans and 
consumers of the natural product, causing them to continue adopt- 
ing synthetic indigo can be met in the following manner: — 
In spite of the energetic and zealous work of the artificial indigo 
manufacturers, who have lost no opportunity of puffing their article, 
the worlds consumption has taken up all the natural indigo produced, 
and the very heavy stocks which have always existed have .never 
been so low as of late. If the Maharajah of Darlangha, as many 
other planters before him, has seen that owing to the low prices 
prevailing the land can be turned into better accou it in many other 
ways, it shows nothing else but that in the comparatively small 
indigo district of lower Bengal the soil is not productive enough 
for this kind of culture, a fact which experts have known for years. 
Other districts continue to prosper satisfactorily, and will go on do- 
ing so if for the next few years better climatic conditions prevail 
than have existed with scarcely a break since 1898. 
The rate of Indian exchange has an important influence on the 
indigo trade. The 1895 to 1896 harvest which was an exception- 
ally good one, producing 160,000 maunds — about 40,000 cases at 
an exchange of is. id. per rupee, yielded such high rupee prices 
that the planter was able to do a large business; in 1896 the ex- 
