411 
a height of 30 feet branches three or four inches in circum- 
ference. . 
'Efficient spraying machines should be found always m 
working order in every estate store, just as the fire appar- 
atus in a gallery of valuable pictures. The cost of even 
the most expensive steam power spraying apparatus cap- 
able of reaching trees of eighty feet or more in height, 
bears an infinitesimal proportion to the value of the trees 
on even a small rubber estate. 
The materials for spraying should also be kept in stock 
so that no delay, is experienced when such work lias to be 
done. My experience of over ten years’ eastern planting 
has been that the delay caused in getting weapons to fight 
the disease lias often caused the task of getting rid of the 
pest to be much more difficult and expensive than it would 
have been had the estates been forearmed. 
Fifty years ago the conditions favourable to the rapid 
spread of disease caused by insect, fungi, or bacteria were 
not so great as at the present day, and the presence of 
35,000,000 trees in an area of some 20,000 square miles is 
in itself a danger, but the weapons which the planters of 
that day possessed for an intelligent fight against these 
organisms were of little use and yielded without confidence. 
In India the loss by wheat rust was some time ago estimated 
at £91,000,000, and in Ceylon the leaf disease of coffee 
caused the extinction of that industry, a loss of at least 
£15,000,000. The work done by sanitation and preventive 
medicine in preserving human life are now historical facts; 
200 years ago the mortality of London was 80 per 1,000, it 
is now about 20. Until a few years ago contagious pleuro- 
pneumonia and foot-and-mouth disease caused immense 
losses of cattle, estimated at 2,000,000 per annum, worth 
probably £30,000,000 ; they have now been almost ex- 
terminated. Plant sanitation and preventive measures, 
can, if invoked, do so much for the preservation of 
cultivated plants, and with the knowledge we now possess 
it is impossible that any disease could so seriously damage 
a big agricultural industry as has been the case in the past. 
Distances Between Trees. 
The average number of trees per acre on rubber 
estates in Malaya in 1908 was 168, or 16 feet by 16 feet 
apart; the statistics for 1907 showed that on the 31st of 
that year the average was 153, or 17 feet by 17 feet apart. 
This, for many reasons, is an improvement. It is to 
be regretted that the cultivation of rubber is too young an 
