Septembeh 16, 1910] 



SCIENCE 



371 



that it was the custom of certain of the 

 Bombay tribes to burn vegetable rubbish 

 mixed as far as possible with the surface 

 soil before sowing their crop, and the 

 value of this practise in European agri- 

 ciilture, though forgotten, is still on record 

 m the books on Roman agriculture. "We 

 can go back to the Georgics again, and 

 there find an account of a method of heat- 

 ing the soil before sowing, which has only 

 xeeeived its explanation within the last 

 year, but which in some form or other has 

 got to find its way back again into the 

 routine of agriculture. Indeed, I am in- 

 formed that one of the early mysteries, 

 many of which we know to be bound up 

 with the practises of agriculture, cul- 

 minated in a process of firing the soil, 

 preparatory to sowing the crop. 



My time has run out, and I fear that the 

 longer I go on the less you will feel that I 

 am presenting you with any solution of the 

 problem with which we set out — "What is 

 the cause of the fertility of the soil?" 

 evidently there is no simple solution ; there 

 is no single factor to which we can point 

 as the cause; instead we have indicated a 

 number of factors any one of which may 

 at a given time become a limiting factor 

 and determine the growth of the plant. 

 All that science can do as yet is to ascer- 

 tain the existence of these factors one by 

 'one and bring them successively under con- 

 trol; but, though we have been able to in- 

 crease production in various directions, 

 we are still far from being able to disen- 

 tangle all the interacting forces whose re- 

 sultant is represented by the crop. 



One other point, I trust, my sketch may 

 have suggested to you: when science, a 

 child of barely a centurj^'s growth, comes 

 to deal with a fundamental art like agri- 

 culture, which goes back to the dawn of 

 the race, it should begin humbly by ac- 

 ■cepting and trying to interpret the long 



chain of tradition. It is unsafe for science 

 to be dogmatic; the principles upon which 

 it relies for its conclusions are often no 

 more than first approximations to the 

 truth, and the want of parallelism, which 

 can be neglected in the laboratory, give 

 rise to wide divergencies when produced 

 into the regions of practise. The method 

 of science is, after all, only an extension of 

 experience. Wlaat I have endeavored to 

 show in my discourse is the continuous 

 thread which links the traditional prac- 

 tises of agriculture with the most modern 

 developments of science. 



A. D. Hall 



THE INTERNATIONAL ESPERANTO CON- 

 GRESS 



America has been the scene of many con- 

 ventions and congresses of a more or less in- 

 ternational character, at which delegates 

 representing many diverse lands and na- 

 tionalities have gathered to discuss subjects 

 of common interest. At these congresses, those 

 attending have been almost as diverse with 

 respect to language as to nationality and the 

 halls of the congress and the places of social 

 gathering and entertainment in connection 

 with it, have usually been fiUed with well-nigh 

 as much confusion as the historic plain of 

 Shinar. Of course, each of these congresses 

 has had its one or more official languages, in 

 which papers were presented and official 

 business transacted; many of those present 

 being unable to take part in or fully enjoy 

 the proceedings, because of lack of sufficient 

 knowledge of some or all of the languages so 

 used — to say nothing of the embarrassment 

 caused when groups of the delegates met 

 casually outside the regular sessions and free 

 intercourse was restricted, or altogether pro- 

 hibited, by the barrier of language. How 

 many of those attending, handicapped by the 

 paucity of their linguistic attainments, have 

 looked back upon such gatherings with more 

 or less regret, feeling that they had lost much, 

 yet knowing full well, that from lack of time 

 or otherwise, the possibility of increasing their 



