April 21, 1910] 



NATURE 



219 



•;ied the currents on the back electrode were practically 

 he same, independently of the sign, while the same 

 nising agent was used. The saturation curves also 

 .esent a peculiarity in a large number of cases. The 

 arves become nearly horizontal at about 240 volts, after 

 \ hich they rise again rather rapidly, and finally become 

 It at about 320 volts. Each of these results is readily 

 xplained if we assume the presence of neutral doublets, 

 iiich are broken up either by collisions or by the action 

 f the field. Further experiments are being made. 



A. E. Garrett. 

 J. J. Lonsdale. 

 Cass Institute, E.C., April 13. 



The Etiology of Lepiosy. 



In Nature of April 7 I have read with interest the 

 article On Dr. Ashburton Thompson's report on "Leprosy 

 in New South Wales." In that report Df. Thompson 

 (one of our foremost authorities) has repeated a state- 

 ment made in sever^|B|^iis former papers avowing distrust 

 in the docirine of coBPI^)n and in the efficacy of isolation 

 as a preventive measure. In commenting, with surprise, 

 on his opinion, the writer of the article savs : — " One 

 would have thought that the success which has attended 

 the practice of isolation in Norway during the past fortv 

 years afforded sufficient evidence of its value even to the 

 most sceptical." 



Now I am quite with Dr. Thompson in his opinion, and 

 must ask to be allowed to state in the clearest possible 

 terms that not only is there no reason to believe that 

 attempts at isolation have taken any share whatever in the 

 diminution of Norwegian leprosy, but much to the contrary. 

 That the disease has declined, and continues to decline, is 

 happily true. The propter hoc, however, fails utterly 

 when we recognise that there has been during this period 

 of its decline no increase whatever in isolation. There 

 has never been in Norway any isolation directed against 

 contagion. The first large leper hospitals in Norway were 

 built by those who did not believe the disease contagious 

 (Dr. Danielsen and others), and who wished simply to 

 prevent marriages and to provide comfortable homes. 

 When the bacillus was discovered, the old theory 

 of contagion was revived, and subsequently certain legal 

 enactments were passed, but there was no increase in 

 arrangements for isolation. Quite the contrary. From 

 that day to this the number of those isolated has been 

 progressively reduced. The lepers have been left at home 

 with their relatives. Yet the disease has declined. It 

 may be noted that it was declining before. It must be 

 obvious that it has been dying out under some other in- 

 fluence, and that the asylums, which no one had thought 

 it worth while to provide, could not possibly be the cause. 

 Let me in passing just remark that during the same period 

 a parallel effort for the extirpation of leprosy was being 

 made in South Africa. There efficient isolation laws were 

 passed, and plenty of accommodation provided. Without 

 flinching, compulsory isolation was carried out. The 



suit has shown a steady and alarming increase in the 

 lisease. 



Compulsory isolation has never been attempted in 



Norway, ancl it has been rigidly enforced in South Africa. 



1 he results have been conspicuously opposite to what 



believers in contagion would expect. The trup explana- 



■on in each case is, I believe, not difficult to give, but 



! must not intrude upon your space further than simply 



I assert that it has nothing to do with belief in contagion 



nd attempts at isolation. Dr. Thompson is, I think, 



nore than justified in the doubts which he has expressed, 



nd it rests with those who in future quote the Norwegian 



acts to show that they really bear the interpretation 



vhich they give to them. Jonathan Hutchinson. 



Sir Jonathan Hutchinson's views on the etiology of 



prosy are well known to be opposed to the generally 



ccepted view that it is an infectious disease caused by 



![ansen's bacillus. They were again brought before the 



cond International Conference at Bergen, August 16-19, 



(og. Nevertheless, the conclusions carried by the delegates 



ere opposed to them. The second International Scientific 



^ onference for the suppression of the disease reaffirmed 



in all aspects the conclusions adopted by the first confer- 



NO. 21 12, VOL. 83] 



ence in Berlin, 1897, when the attitude of Dr. Ashburton 

 Thompson towards the accepted etiology was before the 

 delegates. Leprosy was affirmed to be a disease com- 

 municable from one person to another. No country, no 

 matter what its geographical situation may be, is secure 

 against infection, and the adoption of proper measures 

 against this possibility was recommended : — " Having re- 

 gard to the favourable results which have been obtained 

 in Germany, Iceland, Norway, and Sweden, by isolating 

 the patients, it is desirable that infected countries should 

 adopt the same measures." 



In Norway the law, as formulated again in 1885, gave 

 the Sanitary Commission or Board of Health in each dis- 

 trict the right to order a leper, if he will live at home, to 

 have his own room — at least his own bed ; his clothes 

 ought to be washed separately; to have his own eating 

 apparatus — spoon, fork, knife, &c. If he cannot, or will 

 not, conform to this regimen, he is obliged to enter an 

 asylum. There are those who hold that leprosy is less 

 easily communicated from the sick than is consumption. 

 Dr. Thompson apparently implies that " special precautions 

 therefore seem to be unnecessary " in leprosy because in 

 the past they have been ignored for tuberculosis; but, in 

 the opinion of the writer, it would be of enormous 

 advantage to the public weal if the regulations as apply- 

 ing only to lepers remaining at home could be enforced 

 in regard to tuberculosis. .\s a matter of fact, the success 

 of the leprosy laws in Norway has led, on the initiative 

 of Dr. Claus Hansen, brother of the discoverer of the 

 Bacillus leprae, to the enforcement of analogous regula- 

 tions as prophylactic measures against tuberculosis in that 

 country since 1900. 



It alters nothing in the eftlcacy of segregation that it 

 was applied in Norway by Danielsen before Hansen — 

 Danielsen 's pupil, I believe — had discovered the lepra 

 bacillus. Nor will any useful purpose be served by discuss- 

 ing the efficacy in the application of the law of segrega- 

 tion in Norway as impugned by Sir Jonathan Hutchinson. 

 Dr. Ashburton Thompson's criticisms had been carefully 

 studied by the writer of the article and passed in silence 

 as special pleading — moderate, able, even eloquent — but 

 as unconvincing to him as they have been to the expert 

 delegates at two successive international conferences, the 

 second of which was held in Norway itself. 



The Writer of the Article*- 



Auror 1 Display. 



There was a very fine display here of the aurora 

 between 8 and 9 p.m. The nature of the phenomenon 

 was sufficiently clearly marked to deserve more than a 

 passing notice. 



The curtains and shafts of light all had their origin 

 overhead, radiating from a point a few degrees to tfie 

 north of Castor and Pollux. At times as many as five 

 curtains of light could be seen close together near the 

 radiant centre, some of them spreading over the southern 

 and others over the northern sky. When viewed to the 

 north or south the thin veils showed streaks of light all 

 radiating from the point of origin overhead. When viewed 

 towards the east or west, i.e. end on, the light was most 

 brilliant, and the wavy nature of the hanging curtains of 

 light most marked. 



For at least an hour these curtains or hanging veils 

 of light could be seen originating above and" spreading in 

 all directions, north, south, east, and west. The radiating 

 effect was, of course, due to perspective. There was very 

 little wind at the time, and the curtains of light seemed 

 to travel with it. Another effect which was most marked 

 was that the east and west end of a curtain descending 

 to the north of the point of view curved towards the 

 north, whilst the ends of those curtains which descended 

 to the south of the point of view of the observer curved 

 to the south. This curving only showed itself when the 

 curtains were low down and losing their brilliancy. There 

 could be no doubt but that the whole phenomena originated 

 in a comparatively small area to the north of Castor and 

 Pollux. 



The day had been fine and bright, and the ground was 

 free from snow. Towards half-past nine the sky became 

 hazy. R. M. Deeley. 



North Battleford, Saskatchewan, Canada, 

 March 2S. 



