696 



NATURE 



[February 26, 1920 



could be applied in all Government farms and 

 plantations, but what of the many millions of acres 

 outside? No doubt it would be the most obvious 

 solution of many pests to have a season, like the 

 frost of winter in the United States and in the 

 northern tracts of India, that would kill the cotton 

 plant and the pests as well, so that next year's 

 sowings would stand a chance of being clean. But 

 in many parts of the cotton area of India two 

 cotton crops are taken off the fields every year — 

 the nppam and nadam of Madras, for example. 

 Cotton may, in fact, be seen growing throughout 

 the year in almost any province of India, one crop 

 coming immediately after the other. The soil is 

 often such that a good staple may be raised on 

 one plot of land, and an inferior on another closely 

 adjacent, and the seasons of their production 

 often overlap. Obviously, while there could not 

 be any compulsory orders that 

 would deprive the individual of 

 his rights, the persuasion of per- 

 sonal advantage, once established 

 by the success of neighbouring 

 large plantations, would in a few 

 years secure all that could be 

 desired. 



The salvation of the position is 

 thus the establishment of inde- 

 pendent large cotton plantations, 

 but the most serious difficulty is 

 the discovery of the alternative 

 crop or crops most convenient and 

 profitable. It is not cotton grow- 

 ing only (like tea planting) that 

 has to be faced, but systematic 

 tropical agriculture with a full 

 rotation of crops. This aspect of 

 the problem the report has, of 

 course, not dealt with, and has 

 only general principles to offer. 



The extension into new areas 

 ■ — more especially lands with 

 rich soils that need only en- 

 hanced schemes of water supply 

 to bring them into bearing — is most fascinating, 

 but, as the Indian Committee points out, better 

 results may be looked for from an increase in the 

 average annual yield than from new areas. That 

 view is certainly correct, and should be faced by 

 some practical .scheme, and not by a panorama of 

 committees. • George Watt. 



INDUSTRIAL AND MEDICAL RADIOLOGY. 



'T"'HE extent to which radiology has widened its 

 -*- scope during recent years was strikingly 

 brought out by the exhibition of radiographs held 

 very opportunely by the Rontgen Society at the 

 Royal Photographic Society's galleries during 

 January and February. 



Radiology has usually been regarded as a special 

 province of the physician and surgeon, which pro- 

 vides them with a routine means of quick and 

 exact diagnosis. But radiology is spreading its 



wings into branches of activity far removed from 

 medical endeavour, and the widening of its 

 physical .scope cannot fail to react benehcially on 

 the older branch of the subject. 

 ' Simultaneously comes the awakening of the 

 medical faculty generally to the importance and 

 promise of physical methods and physical agencies 

 as a means of progress in medical research. There 

 is little doubt that within a short time every large 

 and progressive hospital will have a physicist of 

 standing on its staff ; and in this connection we 

 would congratulate the Middlesex Hospital on the 

 good fortune which enables it to establish what 

 we believe is the first medical chair of phvsics in 

 this country. 



In particular, as regards radiology, the physicist 

 will find work to hand in nearly every branch with 

 which he comes in contact. Again, nearly all the 



Fig. 



(a) Radiograph of hand ; exposure 20 mins ; 

 {/>) Radiograph of hand ; exposure i/ioo sec. 



January, 1856. 

 December, 1919- 



(Campbell Swinton.) 

 (Knox.) 



problems of equipment and design are physical in 

 character, and need physicists to tackle them, as 

 .•\merica has already discovered to her profit. If 

 the physicist can further obtain the co-operation of 

 the electrical engineer, all-round improvements 

 should speedily follow. 



What of progress to date? The exhibition re- 

 ferred to here, although confined to radiographic 

 prints, could very fairly be regarded as representa- 

 tive of present-day radiography, and as such it 

 received generous approval from both the public 

 and the Press. Some 200 prints were hung repre- 

 senting work by about thirty of the leading 

 workers. 



As a radiographer rarely takes his work beyond 

 the negative stage, for the good reason that a 

 print shows him no more, but usually rather less, 

 than the negative, it was gratifying to find so high 

 a pitch of photographic technique in the majority 

 of the exhibits. On the other hand, few exhibitors 

 had devoted much care or thought to the mounting 



