making this class of road material. It will be observed
that Messrs. Colfix (Far East) Limited, in their letter
of 27th September, 1929 agree that "the condition of the
roads in Hong Kong is of a very high standard."
4, "Colfix" has been supplied regularly to the
City Council of Gibraltar, and Ceylon ordered a large
consignment some years ago. Gibraltar City Council
still take supplies, and it is therefore assumed that
they find it satisfactory.
We have no reports on
"Colfix" from Ceylon, but we understand that "Coles"
another cold emulsion, is used in that Colony and is now
manufactured in Colombo.
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5. We ship a feir quantity of tar to various Colonial
Governments, tar being considerably cheaper than any of the
proprietary bitumens. The Government of the Gold Coast
reports that tar gives as good a result as bitumen, but
"Colas", which was extensively tried, was a failure in
that Colony. The Government of the Gambia also reports
Zanzibar heve informed
that tar gives the best results.
us that they have tried both "Colfix" and "Colas", and of
the two "Coles" has given the more satisfactory results.
6. We would like to observe that bituminous emulsions
are at best a makeshift. They consist of at least 50%
water and obviously, if imported from ə source of supply
at a considerable distance, must be uneconomical compared
with "hot-mix", whereof the ter or asphalt is obtainable
from a local source of supply, as it is in Hong Kong. In
order to combine the bitumen and water into an emulsion
a flux-soap
is necessary. If the bitumen is to be of any
service in water-proofing the road, the water in its
composition must run off at the time of application.
soep does not always run off with the water and its
The
/presence