352 



SCIENCE, 



[Vol. XVII. No. 438 



ist to apply the results of the general method to practical 

 cases. Liharzik in Vienna measured twenty children regu- 

 larly from the day of their birth to their eighth year, and 

 two hundred boys from their eighth until their fourteenth 

 year. The first to make an investigation of this kind with 

 special reference to school work was Dr. Wretliud, who 

 measured the increases of children during vacations and 

 during the term. In Denmark Dr. Vahl made semi-annual 

 weighings of the girls at Jagerspris. He arrived at the con- 

 clusion that weighings of this kind are the only means of 

 controlling satisfactorily the sanitary conditions of school 

 children. The studies of R. Malling-Hansen indicate that 

 the development dejjends upon climatic conditions, in so far 

 as the winter seems to cause a retarding influence. If this 

 is true, schools in northern countries ought to have longer 

 summer vacations than schools in southern countries, in 

 order to make up for the lesser growth during the cold sea- 

 son. An important iavestigation of this character has also 

 been made in Germany by Dr. Landsberger, in Posen, who 

 followed the growth of one hundred and four children 

 through a period of five years. 



Most of these investigations deal with the growth of the 

 ■whole body, they refer only incidentally to the growth of 

 certain parts of the body. Valuable material on this point 

 is, however, contained in Dr. Landsberger's investigation. 

 He found, for instance, that during school age the diameters 

 of the head change only very slightly, while the growth of 

 the body as a whole is very rapid. The next step to be taken 

 in researches of this kind will be the study of the growth of 

 individual parts of the body in connection with their func- 

 tions. The growth of the hand, together with its increase in 

 strength, ought, for instance, to be studied. The remarkable 

 changes in the curvature of the skull, the relative develop- 

 ment of face and head, in short, the development of each part 

 of the body, ought to be made the subject of most searching 

 and careful inquiry. The results to be obtained from inves- 

 tigations of this kind will undoubtedly teach us how to de- 

 velop the faculties of children each at its proper time. 



ISOLATION OF A CHOLERA TOXINE. 



Hermann Scholl (Berlin. Klin. Woch., Oct. 13, 1890) commu- 

 nicates an interesting paper giving the results of some experiments 

 with a poisonous body isolated from cultivations of the cholera 

 baciUus. According to the British Medical Journal, he thinks it 

 curious that in all previous investigations on the nature of the 

 cholera, toxine cultivations should have been used which had 

 been grown in the presence of air ; whereas, in his opinion, in 

 order to imitate the conditions under which the cholera bacillus 

 gi'ows in the human intestine, the most essential point is that the 

 culture be grown in the absence of air. In this assumption he 

 follows Hueppe and Cartwright Wood, who, he considers, have 

 satisfactorily shown that the cholera bacilli grow in the small in- 

 testine in the absence of oxygen, and that their extreme virulence 

 or rapidity of poison production depends chiefly on this anaerobic 

 growth. Other observers, among whom Petri may be cited, 

 think that this point requires more rigorous proof than has yet 

 been afforded. 



To obtain this anaerobic growth, the author used the method 

 introduced by Hueppe of growing the bacilli in raw eggs, by 

 which means he holds that oxygen is completely excluded. The 

 inoculated eggs were kept for eighteen days at a temperature of 

 36° C. When opened the contents were found to give ofi a very 

 powerful smell of sulphuretted hydrogen, differing in this from 

 cultures grown in air. He describes the white of the egg at this 

 period as being fluid and watery, the yolk firmer in consistence 

 and black in color. In order to test the toxicity of the egg con- 

 tents, five cubic centimetres of the fluid part were injected into 



the peritoneal cavity of a guinea-pig. The animal at first showed 

 signs of paralysis, then convulsive movements, and died at the 

 end of forty minutes. This proved that the fluid egg albumen 

 was very poisonous. 



The author then proceeds to describe his method of isolating the 

 poison. Briefly, it is as follows. The fluid part of the egg con- 

 tents, which amounted to 150 cubic centimetres, was dropped into 

 ten times its volume of absolute alcohol. The white precipitate 

 thrown down was collected and digested with 300 cubic centime- 

 tres of water at 40° C. The effect of this was to dissolve only a 

 very smaU quantity of the precipitate, which was then removed 

 by flltration. Eight cubic centimetres of the transparent filtrate 

 were then injected into the peritoneal cavity of a guinea pig, and 

 caused death in one minute and a half. This fluid entirely lost 

 its poisonous properties on being boiled in the steam sterilizer for 

 half an hour, while a short heating to 75° C. had no such effect. 

 On the other hand, when placed at 40° C. in vacuo, over chloride 

 of lime, the fluid was found next day to be completely inert. 



The author then subjected the poison to the usual chemical 

 tests, and came to the conclusion that it was no ptomaine, but a 

 peptone, differing, however, from the toxo-peptone isolated by 

 Petri from aerobically grown cultivations. This peptone could be 

 obtained in a solid form by dropping the watery solution into 

 eight to ten times its volume of a mixture of the ether and -alco- 

 hol, rendered faintly acid by acetic acid. The resulting precipi 

 tate was found to he insoluble in pure water, but soluble on the 

 addition of an alkali. After repeating this precipitation and re- 

 solution several times, pure ether was substituted for the mixture 

 of ether and alcohol, and the peptone obtained after evaporation 

 as a white bulky substance. A very small quantity of this dis- 

 solved in water was then injected into the peritoneal cavity of a 

 guinea-pig. The animal at once became totally paralyzed. After 

 half an hour convulsive movements of the head and extremities 

 set in, and at the end of five hours the guinea-pig died. The au- 

 thor concludes, as the result .of his experiments, (1) that the poi- 

 sonous peptone, elaborated by the cholera bacilli under conditions 

 of anaerqbiosis from the albumen of the egg, is different from the 

 toxo-peptone of Petri, since the latter was not decomposed on 

 boiling, while the former was ; (2) that this cholera pepto-toxine 

 is much more poisonous than the toxines found by Brieger 

 and Petri in cultures grown under aerobic conditions, since the 

 poison obtainable from a single egg was capable of killing ten 

 guinea-pigs in the space of ten minutes; (3) that these experi- 

 ments are in favor of the contention of Hueppe and Wood that the 

 cholera bacilli, when grown anaerobically, form a greater quan- 

 tity of, and a more powerful, poison than when grown aerobi- 

 cally. 



NOTES AND NEWS. 



The Pedagogical Seminary says that in Darmstadt and other 

 large German cities pot-planfs are given to school chfldren who 

 live in tenements. They are usually three in number and of the 

 same size, with printed directions how to care for them. At the 

 end of a year are exhibitions and prizes. 



— At a meeting of the Royal Society, London, on June 4, the 

 following gentlemen were duly elected fellows of the society : 

 William Anderson, Professor Frederick Orpen Bower, Sir John 

 Conroy, Professor Daniel John Cunningham, Dr. George M. Daw- 

 son, Edwin Bailey Elliott, Professor Percy Faraday Frankland, 

 Percy C. Gilchrist, Dr. William Dobinson Halliburton, Oliver 

 Heaviside, John Edward Marr, Ludwig Mond, William Napier 

 Shaw, Professor Silvanus P. Thompson, and Captain Thomas 

 Henry Tizard. 



— According to the E^igineering and Mining Journal, Professor 

 Salisbury of the United States Geological Survey has made ar- 

 rangements with Professor Smock, in charge of the Geological 

 Survey of New Jersey, to undertake geological studies of the for- 

 mation of the surface in sections of New Jersey, with especial 

 reference to the glacial drift. He will begin work next month, 

 and his study will be confined to Middlesex, Union, and Essex 

 Counties during the summer. Monmouth and Mercer Counties 

 may also be visited. 



