89 
■ component particle, even the molecule, is exposed to the action of 
smoke and is so polymerised, and thus the keeping quality of the 
resulting rubber is assured, and the subsequent vulcanizing test satis- 
factory for years afterwards. 
30. It will be evident that the process differs from all others that 
obtain, and it is, asserted that perfect coagulation and curing of Hevea 
latex can only be effected when the water within the latex is separated 
and disposed of at the same time. Whatever the re-agent may be, 
when Hevea latex is treated in volume, the process is one of coales- 
cing {smoke applied to latex in volume furnishes the same result). In 
volume the re-agent diffuses too slowly, and the particles of caout- 
chouc flock into an agglutinated mass, leaving a residuum of caout- 
chouc in the mother liquor. Such coalesced rubber not only oxidises 
and moulds after preparation, but is also faulty in the vulcanizing 
process. Smoke coagulated rubber on a belt, where the particles and 
globules of caoutchouc are expanded, so that even the molecule is 
exposed and polymerised, improves in keeping, while coalesced rub- 
ber which has not been cured but merely agglutinated, deteriorates. 
31. The process differs too from the Brazilian method in the 
application of dry filtered smoke as compared with the water vapour- 
ish smoke used in Brazil. In Brazilian smoke the three elements of 
Hydrogen, Oxygen and Carbon are excessively high, while other ele- 
ments are only partially generated. The more material difference 
however, lies in the separation of water by this process against its 
absorption in the Brazilian one. 
32. Mention has already been made of vertical adjusting gear 
to accommodate the sag of the belt as it becomes loaded, the weight 
however, is in inverse ratio to the latex supplied, as owing to the 
separation of wacer and caoutchouc there is considerable drip and 
evaporation of moisture. 
33. It is estimated that a belt one foot wide would coagulate 
7% gallons of latex in 3 to 4 hours. Before removal from the belt 
the rubber should be surface dry or slightly hardened for stripping. 
It can then be readily removed and passed through rollers in the 
same operation of stripping, when the remaining water is expressed 
out, and complete drying is effected in a few days, if the rubber is 
smoked daily, for which purpose the smoke chamber could be 
utilized. {A sample of such rubber analysed at the Imperial Institute 
was reported to contain 0.04% moisture and arrived in excellent 
condition free from mould). On estates where there is washing 
and preparing machinery the process would be considerably ex- 
pedited if the belt was stripped at intervals, as the water separates 
and evaporates quicker the less the belt is loaded. It is esti- 
mated that a belt one foot wide and stripped at intervals would 
coagulate from 4 or 5 gallons of latex per hour. An adjustable 
rubber brush is attached to the driving gear which scrapes off the 
freshly coagulated rubber and leaves the surface of the belt compa- 
ratively dry. The rubber is brushed into a funnel and drops into a 
