MANGROVE. 189 



into the first cistern, this was allowed to remain for 

 twelve hours. The infusion was then drawn off to 

 the second, and after standing; a similar period, into 

 the third, and lastly into the fourth, which had been 

 kept empty to receive the saturated infusion, to be 

 farther concentrated by evaporation. The cocks of 

 each cistern, when once turned, were left open to 

 admit the liquid to drain off completely. The whole 

 solution now collected into the evaporating; cistern 

 was exposed to the heat of the sun until concentrated 

 to the consistence of a thick sirup, at which time 

 the lixivium was reduced to about eight gallons ; it 

 was then drawn off dear from its precipitate into a 

 copper vessel, in which it was boiled over a slow fire 

 and kept constantly stirred until the extract acquired 

 a consistence that would just admit of its being 

 poured into the barrel, where, on becoming cool, it 

 assumed the appearance of pitch. 



A like extract was made from Myrobolans* and 

 sent to England. The leather produced from this 

 last substance was found to be similar in appear- 

 ance to that which is obtained when galls are em- 

 ployed. 



In the method of obtaining the extract as above 

 described, the employment of more than two vessels 

 does not appear to be requisite ; the cisterns used 

 were adapted to, and not made for the purpose. 

 The process appears to have been extremely wasteful 

 and defective. By the use of more simple means 

 much better results might have been obtained; 

 results so easily accomplished, that to those who 

 only look on the subject scientifically, it is matter of 

 surprise that the extract should not rather than the 

 bark itself become an article of commerce, and that 

 the advantage of obtaining the tanning principle at a 



* Myrobolans will be farther noticed under the head of dyeing 

 substances. 



