November 4, 19 15] 



NATURE 



261 



lence, but this is a detail, and could be done at a 

 ter date. 



Whatever may be our views as to a democratic con- 

 itution, it must be remembered that it exists, and 

 )thing but obstruction is likely to result from throw- 

 stones at it. It is to be feared that what feeling 

 ^f opposition to science is present in the democratic 

 lind is largely due to the arrogance apt to be shown 

 men of science. Skill and success in a particular 

 mch of science alone do not warrant the demand 

 It their possessor shall be regarded as capable of 

 ^pressing opinions of value on any and all questions 

 public importance. The same may be said, of 

 irse, of any branch of learning. But it can scarcely 

 held that men of science, as such, have hitherto 

 )wn an especially great capacity for business or 

 linistrative ability ; perhaps it may be because 

 pportunity has been wanting. 



We must also confess that ignorance of, or want of 



Iterest in, branches of knowledge outside their own 



amain is not exclusively confined to men of a literary 



legal training. At the same time, it may, I think, 



reasonably asserted that a wide outlook is more 



jmmon amongst men of science than amongst other 



jmbers of the community. 



May I suggest that a more conciliatory attitude than 



it too often assumed with respect to what seem to 



well-meant efforts on the part of Government De- 



irtments would be more to our Interest and for the 



jnefit of the nation? There is, no doubt, a very 



»at deal yet to be done in connection with the posi- 



lon of science in the State. But we may do much 



^n assisting those who are inclined to look with favour 



on our desires and demands, although it may be that 



too many of the positions of authority are filled by men 



lacking in appreciation of the meaning and aims of 



science. We have an opportunity of showing our 



value to the nation, and, if we use it well, greater 



duties and responsibilities will follow. 



W. M. Bayliss. 

 University College, London, October 23. 



[We do not doubt for a moment that the gentlemen 

 mentioned by Prof. Bayliss take a sympathetic interest 

 in the promotion of scientific research, but this can 

 scarcely be regarded as specially enabling them to 

 administer a scheme to promote the co-ordination of 

 science and industry. What we particularly object to 

 is the assumption, made in all Government offices, 

 that men without scientific knowledge are alone 

 capable of controlling scientific departments and com- 

 mittees. The executive officers of the Committee and 

 Advisory Council on Scientific and Industrial Research 

 represent only one illustration of a principle for which 

 there is no substantial basis. Prof. Bayliss seems dis- 

 posed to concede this principle : we are not. He sug- 

 gests that men of science do not possess much business 

 or administrative capacity : we do not accept this 

 generalisation ; and we hold that they could scarcely 

 be less effective and less enterprising than administra- 

 tors trained in unscientific schools. No one supposes that 

 skill and success in science give authority to opinions 

 expressed on other subjects, but neither does work in 

 literary and legal fields create ability to deal with the 

 practical problems of science and technology. Science 

 has too long been content to occupy a subordinate 

 position in the national executive ; and the main object 

 of our article was to assert its claims to a higher 

 place. — Ed. Nature.] 



A New X-Ray Technique. 



The remarkable therapeutic action of radiations with 

 a range of wave-length from 3-8x10-* cm. to 

 0-99 X lo-' cm. is now generally known and recognised 



NO. 2401, VOL. 96] 



by the medical profession. Between the limits 

 A= 1-72x10-' cm., the shortest wave emitted by a 

 Coolidge tube, and A = o-99Xio-' cm., the length of 

 the waves of gamma rays from radium C, there is a 

 gap which has so far defied all attempts at bridging. 



Meanwhile, physico-physiological laboratories have 

 their hands full with many problems concerning the 

 actioh of the numerous radiations already available. 

 Research work in this direction can only progress 

 slowly; far more slowly, in fact, than investigations 

 undertaken in perhaps any other branch of physics. 

 But the prospect of final success, and in any case the 

 task of alleviating sickness and pain, is so compelling 

 that he who attacks this problem in the true spirit 

 of science is unconscious of any sacrifice. 



Now the various strong inducements presented to 

 the physician by this new method of treatment have 

 led to the hasty accumulation of a large number of 

 facts and a mass of data which serve at the present 

 time as the basis of modern X-ray technique. In the 

 absence so far of any wide generalisation emanating 

 from laboratory work, this necessary knowledge has 

 been largely acquired by the elementary process of 

 trial and error. 



I wish, however, to refer here only to that part of 

 the subject which relates to the treatment of deeply- 

 seated tumours and to point out that so astonishing, 

 both as regards action and inaction, are many of the 

 results of treatment by this pleasant and painless 

 means that it is very desirable to pursue the matt'^r 

 as systematically as possible. From the outset, the 

 physician has met with the difficulty of administering 

 a large dose of radiation to an internal region of the 

 body without endangering the more superficial tissues. 

 It has hitherto been usual, therefore, to make com- 

 paratively short exposures, taking care at the same 

 time that the intervals between them be not too brief. 

 In order to obviate this drawback the method of 

 "crossfire" has been largely developed on the Con- 

 tinent, the patient being mapped out into several 

 definite areas and the exposures made through several 

 "ports of entry," with the rays always pointing 

 towards the seat of disease. 



It occurred, however, to the writer some months ago 

 that by a suitable means of rotating a single X-ray 

 tube and screening off with lead the rays from it, 

 except a comparatively small pencil of them, it would 

 be possible to bring to bear upon a deeply-seated region 

 in the body a far greater amount of radiant energy 

 in a given time than existed at the skin surface during 

 treatment. Intensity of radiation is defined as the 

 energy falling upon one square centimetre of receiving 

 surface, and it is clear that if a conical beam of 

 X-rays could be sent towards a diseased region so 

 that the apex of the cone rested upon the neoplasm, 

 the intensity of radiation there would be far greater 

 than at the skin surface, where the area traversed 

 by the rays is larger. But this would involve a source 

 of rays consisting of a beam of large cross-section 

 and the ability to concentrate it to a focus, the former 

 condition being difficult to obtain and the latter im- 

 possible. 



Nevertheless, since time enters into the question in 

 the case of therapeutic action it is possible to approxi- 

 mate to the above conditions by the simple device of 

 attaching the X-ray bulb to the circumference of a 

 slowly revolving wheel of about 18 in. diameter, and 

 with its axis pointing- towards the diseased region. 

 The screen is arranged to give a slanting beam that 

 makes a convenient angle with the axis of rotation. 

 Thus a hollow cone is swept out by the revolving 

 pencil of rays, and it becomes possible to give a dose 

 of radiation to a deeply-seated tumour ten or more 

 times as great as that received by the skin. In this 



