538 C^/k/ Fal^rics of the Ela/lic Gum. 



G£ all the cloths upon which I made experiments, nankeen, from the ftrength and qua- 

 lity (jf its fabric, appeared the bell calculated fortoating with the gum. The method I 

 followed ill performing this, was, to lay the cloth fmooth upon a table, pour the milk 

 upon it, and with a ruler to fpread it equally. But (hould this ever be attempted on a 

 larger fcale, I would recommend the following plan : to have a ciftern for holding the 

 milk a little broader than the cloth, to be covered with a crofs bar in the centre, which 

 muft reach under the furface of the milk, and two rollers at one end. Having filled the 

 ciltern, one end of the piece of cloth is to be palTed under the bar, and through between 

 the rollers ; the former keeping the cloth immerfed in the milk, the latter in preffing out 

 what is fuperfluous, fo that none maybe loft. The doth can be hung up at full length to 

 dry; and the operation repeated until of whatever thicknefs wanted. For the reafons 

 above-mentioned, care muft be taken that one fold does not come in conta£l with an- 

 other while wet. 



Having obferved that moft of the patent catheters and bougies made with a folution of 

 the elaftic gum, whether in ether or in the eflential oils, had either a difagreeable fticki- 

 nefs, or were too hard to admit of any advantage being derived from the elallicity of the 

 gum, I was induced to make fome experiments with the milk towards removing thefc 

 objections. 



From that fluid, by evaporation, I made feveral large fized bougies of pure gum, which, 

 from their over-flexibility, were totally ufelefs. I then took fome flips of fine cloth co- 

 vered with the gum, which I rolled up until of a proper fize, and which I rendered folid 

 by foaking them in the milk, and then drying them. Thefe poflefled more firmnefs than 

 the former, but in no degree fufficient for the purpofe intended. Pieces of ftrong catgut, 

 coated, with the gum, I found to anfwer better than either. 



Befides an efFe£lual cloathing for manufacSlurers employed with the mineral acids, which 

 had been long a defideratum, this fubftance, under different modifications, might be ap- 

 plied to a number of other ufeful purpofes in life; fuch as making hats, great coats, boots, 

 &c. for failors, foldiers, fifliermen, and every other defcription of perfons who, from 

 their purfuits, are expofed to wet ftockings ; for invalids, who fufFer from damps ; bath- 

 ing caps, tents, coverings for carriages of all kinds, for roofs of houfes, trunks, buoys, &c. 



This extraordinary vegetable produ£l;ion, in place of bein^ injured by water, at its ufual 

 temperature * is preferved by it. For a knowledge of this circumftance I am indebted to 

 the Chinefe. Having fome years ago commiflloned articles made of the elaftic gum from 

 China, I received them in a fmall jar filled up with water, in which ftate I have fince kept 

 them without obferving any figns of decay. 



Should it ever be deemed an objeft to attempt plantations of the elaftic gum vine in 

 Bengal^ I w'ould recommend the foot of the Chittagong, Rajmahal and Baiiglipore hills, as 



• From an account of experiments made with the elaftic gum by M. Groflart, inferted in the Annals de 

 Chimie foT ly^z, it appears, that water, when boiling, has a power of partially diffolving the gum fo as 

 to render one part capable of being finally joined to another by prelTure oaly. 



3 fituations 



