PROCEEDINGS OF THE THIRD ENTOMOLOGICAL MEETING 15 



forget the seemingly trivial observation which led to this. In one of 

 his experiments at the Royal Institution in London Faraday showed 

 that when a magnet is brought suddenly near a coil of wire a slight 

 electric current is induced in the coil. The experiment does not appear 

 very impressive and a lady in the audience probably expressed the general 

 sentiment when she asked afterwards, " But, Professor Faraday, even 

 if the effect you explained is produced, what is the use of it ?" To which 

 Faraday repKed, " Madam, will you tell me the use of a new-born 

 child ?" 



Nearly all the great inventions of our modern world, wireless tele- 

 graphy, the telephone, the aeroplane, radium, anaesthetics and anti- 

 toxins, spectrum analysis and X-rays, all had their foundations in purely 

 scientific work and were not the result of deliberate intention to make 

 something of service to humanity. Scientific subjects do not progress 

 necessarily on the lines of direct usefulness. Their applied side may 

 come many years after the actual discoveries themselves. Applying 

 this to economic work in Entomology, as I said just now, provided that 

 our work is accurate and honest, every smallest observation will ulti- 

 mately prove to be of use whether in the immediate future it seems 

 likely to be practically useful or not. As Aristotle said, " Let us first 

 understand the facts, and then we may seek the cause." 



I am inclined to think that the control of insect pests in the future 

 will be based on the dictum that " prevention is better than cure," and 

 that such prevention will be attained by an exact knowledge of each 

 insect concerned, knowledge so exact that it will be known exactly under 

 what conditions trouble is likely to occur, so that preventive measures 

 can be taken before any actual damage has been done. This is not the 

 case at present, as most of our so-called control measures are mere palli- 

 atives, aiming only at minimizing damage which is already being done. 

 I think that the control methods of the future will be based on fore- 

 casts of the increase to destructive numbers of the particular insect 

 concerned and that such forecasts will be based on an intensive study 

 of a large number of exact records of occurrence of such insect. Why, 

 for instance, does Xylotrechus quadripes, the Coffee Borer, appear in 

 some years in swarms, whilst in other years this beetle is by no means 

 plentiful ? Why do locust swarms invade India in some years and not 

 regularly every year ? I think that, when we have accumulated exact 

 records of such visitations and compare them with weather statistics and 

 other records, we may find some correlation between them and, if so, 

 we shall then be able to make insect-pest forecasts which can be used 

 to nip the impending increase in the bud. But we shall only be able 

 to do this when we have accumulated sufficient exact records of the 



Vol. I 



