August 7, 1891. J 



SCIENCE. 



73 



of strength or weight, and the chest-sounds were healthy. The 

 men, however, were not of a vigorous type, and they were all ac- 

 customed to have a cold bath summer and winter. It seemed 

 likely, especially in winter, that the sudden application of in- 

 tensely cold water to the whole surface of the skin too suddenly 

 raised the internal blood -pressure, and hence the oozing of the 

 blood through the walls of the capillary vessels lying beneath the 

 lining membrane of the throat or larynx, or possibly the lungs. 

 In any case, whatever the true explanation may be, the fact 

 stands out that the unpleasant symptom disappeared as soon as 

 the temperature of the icy cold water was reasonably increased. 

 The practice of taking a cold bath is so universal nowadays that 

 it is perhaps as well to know that although the strong man may 

 indulge in it with unmixed benefit, it may cause in the weak man 

 a symptom which fills him with anxiety. 



Lannelongue's Treatment of Tuberculosis. 



The object aimed at by this method, as stated by the Lancet, is 

 to bring about a sclerosis of the tubercular tissue, whatever may 

 be its seat. The cases thus far treated have been mainly those of 

 surgical tuberculosis. 



Experiments have shown that chloride of zinc produces a re- 

 markable fibroid change in the normal tissues of animals ; and, as 

 might be expected, the same fibroid transformation is brought 

 about by the same agent in morbid tissues in general, including 

 the tubercular. This chemical compound may be said to fix the 

 anatomical elements by killing them, for it obliterates the capilla- 

 ries and smaller vessels around where it has been deposited. An 

 inflammatory action is thus set up in the vascular walls, which 

 narrows the calibre of the surrounding vessels for a considerable 

 distance from the initial point. But over and above this another 

 local change of the highest import is brought about. Very rap- 

 idly — even within a few hours — there is produced in the altered 

 tissues, by transmigration, and probably also by cell proliferation, 

 an enormous afflux of new anatomical elements. These young 

 cells cause fresh oedema of the periphery of the granulation 

 growths, and infiltrate the tubercular neoplasm to the fullest ex- 

 tent. From this moment the struggle sets in between the accu- 

 mulated elements and the bacilli, especially between the migratory 

 cells and the microbes, to the detriment of the latter. However 

 it may be as to the strife between cell and bacillus, the elements 

 of the morbid growth which the chloride of zinc had destroyed 

 are re-absorbed slowly, and finally disappear. The young cells, 

 on the contrary, organize with great activity, and form a firm 

 fibrous tissue, which is met with in appreciable quantity as early 

 as the day next after the injection. 



Following the sclerosis in articular fungosities, there is produced 

 a thickening and subsequent condensation of osseous tissue if the 

 periosteum be involved in the reparative process, as was the case 

 in the examples of osteo-arthritic disease cited by the author. 

 The remote results, so far as it is yet possible to judge, show a 

 marked tendency for the sclerosed elements to be replaced by a 

 more pliable connective tissue. As a consequence, the diseased 

 parts regain their suppleness and their form, while locomotor 

 functions are preserved entirely, or at least to the limits present 

 at the beginning of the treatment. 



The Artificial Production of Dental Caries. 



For the past year Mr. Sewill, following other experimenters in 

 the same field, has been endeavoring to produce caries in extracted 

 teeth ; and certainly the microscopical appearances presented by 

 the sections shown at the Odontological Society, says the Lancet, 

 differed but little from those of natural caries. He found that 

 the best mixture of organic substances for the purpose was one 

 part of bread to eight of saliva. Meat with saliva remained alka- 

 line, and if a small quantity of acid were added became again 

 rapidly alkaline. Albumen, whether as white of egg or other 

 forms, acted in the same way. Saliva and starch produced little 

 acid, which was soon exhausted. 



The teeth were immersed in the mixture in glass- stoppered bot- 

 tles, and kept at a temperatrure of 35° to 37" C. The bottles were 

 unstoppered about once a day for examination ; this, of course, 

 admitted air, and if the mixture became putrid, it at once showed 



an alkaline reaction, in which case the teeth were taken out, well 

 washed, and the mixture renewed. The mixture became rapidly 

 acid, and remained so (unless putrefaction to a large degree su- 

 pervened) for from three to five weeks. The acids present were 

 acetic and lactic; of the former 5 per cent and of the latter 0.5 

 per cent were found after three weeks. The effects upon the tissues 

 were precisely the same, both macroscopical and microscopical, 

 as in natural caries. As in natural caries, the decay was found 

 to commence most readily in places where there was ill-formed 

 enamel or flaws or fissures which allowed access to the dentine, in 

 which tissue the caries progressed more rapidly than in enamel. 

 Cementum resisted longer than enamel, but at length yielded, and 

 allowed the dentine beneath to be invaded. Discoloration was 

 often present, and it was found that carious dentine readily took 

 up stains from such substances as are often admitted to the mouth 

 in medicines or articles of food. Microscopically the translucent 

 zone is well shown, also the " pipe-stems " appearance in trans- 

 verse sections, and the dentinal tubes are filled with micro-organ- 

 isms, just as in natural caries. 



The conclusions that Mr. Sewill draws from these experiments, 

 and from the facts that caries takes place in natural teeth which 

 are used as artificial substitutes, are, that caries is entirely due to 

 external agents, and that vital action in no way modifies the dis- 

 ease. 



NOTES AND NEWS. 



The university extension work has been organized in Chicago. 

 Cleveland, Indianapolis, Fort Wayne, and Altoona are among the 

 latest applicants for branches. 



— Accessions to the membership of the Society for the Exten- 

 sion of University Teaching continue to be sent in at the rate of 

 nearly a hundred a week. The best indication of the national 

 character of the work is found in the wide area from which these 

 applications are received, every State in the Union being now 

 represented on the rolls. 



— The work of the St. Paul (Minn.) Academy of Science con- 

 tinues to meet with increasing support and encouragement. The 

 museum is receiving many additions, its rooms being permanent 

 and well adapted for the purpose. Persons willing or desirous of 

 adding to its collections by loan, gift, or exchange, are invited to 

 correspond with Professor W. F. Phelps, chairman of the com- 

 mittee on museum, or with Mr. C. B. Scott, curator. It is grati- 

 fying to learn that the university extension classes, organized un- 

 der the auspices of the academy, and conducted by professors 

 from the State University, from Carlton College, and other near-by 

 points, have proven quite successful and promise much for the 

 future. 



— The heavy sentence of four years' imprisonment, in addition 

 to fines, imposed in France recently on four persons connected 

 with the alleged sale of the secret of melinite to an English firm 

 gives a new turn to that strange affair. It was recently announced 

 by the French minister of war that M. Turpin, the inventor, and 

 Captain Triponfi, the agent of the English firm, really had nothing 

 of value to the French government to negotiate for, and that the 

 most important part of the invention — the means of exploding 

 melinite after it has been united with another substance in the 

 shell — remained in the sole possession of the government. This 

 second substance, according to the New York Times, is cresilite, a 

 nitro-cresol obtained from a coal-tar product ; and after two-thirds 

 of the space in the shell has been filled with it, melinite is rammed 

 in — a fact which sufficiently indicates that both products can 

 be safety handled, and can be exploded only by a powerful de- 

 tonator. 



— In its latest report the Board of Health of the city of Boston 

 says: " We are of the same opinion now as we were when we 

 made our last annual report, that the large expense to the city, 

 and the perpetual nuisance which attends the storing and handling 

 of garbage, should be abolished by burning it in the kitchen, 

 where it first appears as waste, and before decomposition has be- 

 gun to make it offensive. By this method the only expense to be 



