expenses may be shared, and the more intelligent of the coolies on 
the interested estates duly instructed in their work. This policy 
was adopted by the Belgian Government on the higher reaches of 
the Congo, and here these Amazon experts succeeded in extract- 
ing from the African indigenous Hevea (sic) by careful extraction 
and curing, a rubber called Ruki (after an adjacent village), which 
is called actually better than Para itself, with a lower percentage 
of rubber resins, and lower percentage of foreign matter, thus 
offering a higher tensile strain. Naturally, this secured a better 
price in the European markets than Para itself, and is in great 
demand. This care, of course, is the ambition and goal of every 
grower. The same course was adopted by the Liberian Govern- 
ment in reference to the rubber trees near Monrovia, and at first it 
exported some excellent samples, truly capable of improvement ; 
but, upon the departure of the rubber experts, the native Krew boys, 
either fronPwant of care, or pure and simple laziness, abandoned 
due care, and consequently, Liberian rubbers are to-day more or 
less under a cloud in the market. The first and great care neces- 
sary, and even imperative, is absolute cleanliness in the extraction 
of the milk : the bark of the tree to be tapped should be carefully 
cleansed, the knife to be used carefully cleaned, the V shaped cuts 
and perpendicular central channel all should be perfectly clean 
before the milk is allowed to run, the collecting cups and milk can 
also need attention in this respect. The necessity of this seeming- 
ly excessive care is clear, in view of the fact that often-times the 
smallest particle of grit present may cause endless trouble to the 
manufacturer, depreciating or destroying the quality of his work. 
The manufacturer, to start with, must have his raw rubber perfectly 
pure. To this end the imported gum is first of all heated, then torn 
and rolled between friction rollers, under a stream of water to re- 
move the foreign matter that may have been introduced through 
the carelessness of the collector* This constant tearing and rolling 
necessarily reduces the original strength of the gum. The greater 
the proportion of foreign matter to be removed, the greater the 
percentage of the loss of tenacity of the material. For instance 
the removal from' firm Paia rubber of even 5 per cent, of impurity, 
will oftentimes occasion the loss of 20 per cent, in strength and 
vitality of the resulting product. It is oftentimes the one little 
grain of sand which does the greatest mischief. As an illustration, 
may we take the case of a cycle tyre inner tube. If a little grain 
of sand is allowed' to get into the milk in collecting, these little 
particles are the most difficult to remove mechanically by washing, 
hence the grain of sand eventually finds itself embedded in the 
thin skin of the cycle tube. Upon inflation the grain of sand 
pops out, leaving a point of least resistance, subsequent in- 
flations tend i/o form a bubble, in a few days the bubble bursts ; 
the sand has done its work, and the tube requires mending. Manu- 
facturers know this to their cost, 'and are therefore willing to 
pay highly for a perfectly clean reliable rubber, and look with sus- 
picion on either “gritty rubber " or “barky rubber ”. In the lat- 
ter case the embedded fragments of bark or vegetable matter being 
