204 
can be varied with the aperture of the cylinder and the fineness 
of the sand. When the whole of the sand has passed into the 
hanging receiver, the pointers are adjusted to the marks previously 
made and a reading taken which according to the elasticity of the 
rubber being tested may be 200 per cent or more of the original 
measurement viz., 5.0 centimetres. 
The stop-cock at the bottom of the hanging receiver is then 
opened and the sand is allowed to flow out the strain being thus 
as released as gradually it was imposed. 
When the vessel is empty it is removed and after two minutes 
the pointers are again adjusted and a third reading taken which 
according to the resilience of the rubber approximates to 5 centi- 
metres the original length. 
In a series of tests made from pieces of biscuit rubber pieces 
taken from different places of the same biscuit gave practically 
exact results, while samples of biscuits of from plantations of 
different age varied considerably. In these preliminary tests of 
the efficiency of the apparatus the results showed that the figures 
obtained were reliable, and though I myself or others may be able 
to improve or simplify the apparatus, yet as a practical curing 
house and office that it should be of use in arriving at a fixed 
method of judging the qualities of rubber either plantation or 
Brazilian para. 
The use of this apparatus on various qualities of rubber and 
under varying conditions has given me useful data in relation to 
the physical qualities of plantation rubbers. The length of time 
during which extension takes place when a weight is gradually 
imposed, and after the weight has "’all been placed and the length 
of time for recovering back to approximately the original dimen- 
sions show interesting variations in different qualities of rubber. 
It is the physical qualities of resilience and elasticity that are 
of value in India rubber and the chemical compositions are only 
of interest in so far as they are correlated with these physical 
properties. A physical test is therefore the most important, and 
this is recognised by the most .careful manufacturers who test for 
resilience after they have ifranufactured i.e. mixed and vulcanised 
their rubber. 
The apparatus as described was made from my drawing by 
Messrs. Baird and TATLOCK, but owing to my absence in the 
-Far East certain improvements and modifications which occurred 
to me after designing the plant of the machine could not be made. 
J. B. CARRUTHERS. 
A PARASITIC FUNGUS ON TAPIOCA. 
In March of this year, Mr. SNODGRASS brought to the office of the 
Botanic Gardens from Malacca a number of leaves of Tapioca, 
