373 



manufactories of rubber goods on a large scale in the rubber districts. 

 It is notorious that there are practically no large manufactories in any 

 part of the tropics. All or nearly all attempts at starting anything 

 except strictly local manufactures even in the most suitable locali- 

 ties have proved complete failures. The continuous work in one 

 place does not suit the Oriental at all, least of all the Cingalese, 

 Chinese and Malay, the workers of the rubber region in the East. 

 Till the manufacturing classes of Europe can be so acclimatized 

 as to settle in the hot damp rubber regions and without deteriora- 

 tion of character and stamina populate the equatorial belt, it is not 

 at all probable that any large manufactories of vulcanized goods 

 will ever become practicable here. 



I may conclude these notes by calling attention to the immense 

 amount of invaluable botanical chemistry already done by the 

 Scientific Department of the Imperial Institute for the Empire and 

 particularly the Colonial portion of it. The requirements of research 

 into the chemistry of plants and of the raw products of the tropics, 

 and also of scientific agriculture in all our possessions, are enormous, 

 the scanty and tardy recognition of their importance to the whole 

 empire by the Government ludicrously meagre, but it is satisfactory 

 to see that at length some appreciation of this work is being felt, 

 and Professor DuNSTAN's Laboratories at the. Imperial Institute 

 are leading the way to a full knowledge of our resources and the 

 way to use them. 



H. N. R. 



DESTRUCTION OF RATS IN COCHIN-CHINA. 



An article by M. QuESNEL in the Journal d' Agriculture Tropicale 

 on this subject is worth attention as the plague of rats in the paddy- 

 fields is often very destructive in the Peninsula. The experiments 

 were made with the Danysz Virus which has been tried here and in 

 Java without success. M. QUESNEL attributes this to the deteriora- 

 tion of the Virus on its way out to the East. In one case the Virus 

 proved successful, a crab was opened and some Virus put beneath 

 the carapace, which was closed again, and the crab put on a pile of 

 rubbish between a garden and a paddy-field. Next day an enormous 

 rat was found dead by each crab and two more in the mouths of 

 their burrows in the rice-fields. One Virus tube was enough for 

 from 50 to IOO crabs. It is suggested that the Virus should be used 

 when the rice- fields are flooded and the rats have taken refuge in 

 the higher ground of the mounds in the flooded area. Except in 

 the instance given above the use of Danysz Virus does not seem to 

 have been any more successful than it has in Java and Perak. 



An Annamite method of catching rats is also described. At 

 some spot in a rice-field a pile is made of alternate layers of brush- 

 wood and straw to 5 or 6 feet in height. Baits of crabs, fruits, etc. 

 are put in and the pile left for 8 to 15 days. It is then surrounded 

 with a close bamboo screen, of about 6 feet tall, and the natives 



