NA TURE 



{Dec. 4, 1884 



suffering from dysentery, also in diarrhoea of children, in 

 animals poisoned by arsenic, in impure water from various 

 parts around Calcutta, indeed wherever he met with a 

 fluid containing bacteria he examined it for comma- 

 bacilli, without however finding any (except in one 

 instance, see No. S). He specially mentions that he has 

 tested saliva and the material on the teeth and tongue, 

 which is always full of bacteria, but always with a negative 

 result. He further refers to his own previous large 

 experience in the cultivation of bacteria, and that of others 

 who have worked at cultivation, this experience being 

 against the presence of this organism, except in cholera. 

 From these facts he feels himself warranted in stating 

 that " the comma-bacilli constantly accompany cholera, 

 and are never found elsewhere." 



(7) No other conclusion can be arrived at than that 

 these bacilli are the cause of cholera. 



{a) It might be said that the choleraic process merely 

 favours the growth of this bacillus. But on this suppo- 

 sition every one must have comma-bacilli in his body, 

 because they are present in cases of cholera occurring in 

 widely-separated parts of the world. This, however, is 

 not the case (No. 6). 



(b) As the result of the disease, conditions arise which 

 cause the transformation of some ordinary bacterium into 

 comma-bacilli. There is no evidence of such rapid 

 transformation of one form of bacterium into another. 

 The only known case of alteration in the properties of 

 these bodies is the attenuation of anthrax bacilli, &<;., 

 but this is merely an alteration in pathogenic action ; 

 their form and mode of growth remain unaltered. Out- 

 side the body Koch has not, during the course of his 

 investigations, got the slightest evidence of any change 

 in these bacilli. 



(c) The only conclusion which remains is that the 

 cholera process and these bacilli stand in close relation 

 to each other — in a relation of cause and effect. 



(8) Although by experiments on animals direct evidence 

 that the comma-bacillus is the cause of cholera has not 

 been obtained, there are various observations which are 

 almost as good as experiments on man. 



In one case in a village near Calcutta Koch examined 

 the water of a tank which supplied the inhabitants with 

 drinking-water, &c. A number of cases of cholera had 

 occurred, and when the water was examined the epidemic 

 was at its height. Comma-bacilli were found in the 

 water in considerable numbers. At a later period, when 

 there were only few cases of illness, the comma-bacilli 

 were few in number, and only found at one part of the 

 tank. This was the only instance in which Koch found 

 these bacilli outside the body. He further refers to the 

 occurrence of disease in washerwomen, and infection 

 from clothing soiled with cholera dejecta. 



(9) The natural history of the disease corresponds with 

 the various characteristics of this organism. 



The bacilli grow rapidly, soon reach their highest point 

 of development, and then die : this corresponds to what 

 occurs in the intestinal canal. Under ordinary circum- 

 stances these bacilli are destroyed in the healthy stomach. 

 This corresponds to the clinical facts of cholera, for, of a 

 given number of individuals exposed to cholera, only 

 some are taken ill, and those almost all suffer from 

 disturbance of digestion— either catarrh of the stomach 



or intestine, or overloading of the stomach, &c, with 

 indigestible food. The disease dies out in places where 

 the conditions for its continuance are unfavourable : the 

 bacilli have no spores. 



These are the facts on which Koch's views are based ; 

 lately, however, two researches have been published 

 which strike at the root of the theory, and which try to 

 show that these bacilli are not peculiar to cholera. Dr. 

 Koch has also published a reply. 



The first of these researches is that of Dr. Lewis, who 

 finds bacilli in the mouth microscopically identical with 

 the comma-bacilli. Koch's reply ( Deutsche Med. 1 1 'oelien- 

 schrift, No. 45, 1SS4) is that he is well aware of the fact that 

 organisms somewhat resembling the cholera bacillus are 

 present in saliva, but that he does not diagnose these bacilli 

 by microscopical characters alone, that if these bacilli are 

 cultivated they will be found to be quite different from 

 those present in cholera. For instance, they will not 

 grow at all in the neutralised cultivating gelatine in which 

 the cholera bacilli grow rapidly. The other research is 

 by Finkler and Prior, who stated that they had found 

 the comma-bacillus in cases of cholera nostras, and who 

 further described spore-formation in them. Koch suc- 

 ceeded in obtaining a specimen of their " pure " cultiva- 

 tions, and found, on shaking up a minute quantity with 

 the liquefied gelatine and pouring it out on a glass plate, 

 that they had a mixture of four different bacilli, and that 

 none of them were the comma-bacilli described by him. 



Koch further adds the interesting fact that he has again 

 taken up the experiments on the lower animals (piesum- 

 ably, from the context, on dogs and guinea-pigs), and that 

 by injecting minimal quantities (as little as the 100th 

 of a drop) of the cultivations of comma-bacilli into the 

 small intestine, the animals have as a rule died in one 

 and a half to three days, and the post-mortem appear- 

 ances of the intestine were the same as in acute cases of 

 cholera, the fluid in the intestine also containing enormous 

 numbers of comma-bacilli. 



In two cases of cholera nostras, and in a diseased bee, 

 the writer found bacilli which microscopically closely re- 

 sembled the comma-bacilli, but it was found that they 

 did not grow in the neutralised gelatinised material, and 

 were therefore not the same organism. 



THE HA YTIAN NEGROES 



Haytij or, The Black Republic. By Sir Spenser St. John, 



K.C.M.G. (London: Smith, Elder, and Co., 1SS4.) 



WHATEVER theory may be adopted regarding the 

 fundamental equality or disparity of the human 

 races, a truthful and unbiased account of the present 

 social condition of the Haytians, by a competent observer, 

 must necessarily prove a valuable contribution to the 

 study of psychological anthropology. These conditions 

 are eminently satisfied in the work before us, written as it 

 is by a man personally above suspicion of any unworthy 

 motive, by a statesman who has associated for some five- 

 and-thirty years with every variety of coloured peoples, 

 by a distinguished diplomatist, who, as British Minister 

 and Consul-General, has resided for twelve years in Hayti 

 itself. On the other hand, no more favourable field could 

 be selected for a study of the negro race than this western 

 and smaller division of this large West Indian island, 



