August 3, 1900.] 



SCIENCE. 



195 



The curious observation is made by P. Vil- 

 lard in the last Comptes Bendus, that at the 

 temperature of 1000° fused silica, SiO^, is per- 

 meable to hydrogen. 



The abstract of a paper read before the Chem- 

 ical Society (London) by John Wade on the 

 constitution of hydrogen cyanid, is given in the 

 last number of the Proceedings. From reactions 

 with alkyl iodids and sulfates, it has appeared 

 as if potassium cyanid had the constitution KCN 

 while that of silver cyanid is AgNC. Wade 

 now shows that when potassium cyanid is heated 

 with alkyl potassium sulfate at a lower tempera- 

 ture, the isomeric isocyanid is often the princi- 

 pal product. He further finds that practically 

 all the isocyanids can be converted into cyanids 

 (nitrils) by heat. Since the formation of nitrils 

 in the above interaction is thus accounted for, 

 one of the chief arguments for the nitrilic con- 

 stitution, HON, of hydrogen cyanid disappears, 

 and it seems possible that HNC represents the 

 constitution of the acid, and that all the cyanids 

 have an analogous constitution. 



J. L. H. 



MEDICAL EXHIBITS AT PARIS. 



The Paris correspondent of the British Medi- 

 cal Journal gives the following account of some 

 of the medical exhibits at the Paris Exposi- 

 tion : 



In the Pavilion des Armees de Terre et de 

 Mer, at the end nearest the Pont de I'Alma, we 

 first enter the Salon Pasteur. On either side 

 of the entrance are cabinets filled with cultures 

 of different microbes. In the center of the 

 room is the bust of Pasteur on a pedestal, 

 round the base of which is an octagonal case 

 containing a retrospective exhibition of the 

 work of Pasteur. Here we see the manuscript 

 of the thesis presented before the Faculty of 

 Science in 1847 on molecular dissymmetry; the 

 microscope used by Pasteur to measure the 

 angles of crystals, and models of various crys- 

 tals ; his work on fermentation, with the origi- 

 nal apparatus used for the study of butyric acid 

 fermentation, and the apparatus for the study 

 of living anaerobic microbes. Pasteur's re- 

 searches on spontaneous generation are illus- 

 trated by the apparatus to prove that calcined 

 air contained no germs, and the flasks used in 



the experiments on the organized dusts in the 

 atmosphere, and opened by him on Octo- 

 ber 3, 1860, at the summit of Mount Poupet. 

 In connection with his investigation into the 

 diseases of wines and beer, flasks for the pure 

 culture of yeast and experiments on the ag- 

 ing of wines are shown. The microscope 

 used by Pasteur in his investigation of the 

 diseases of silkworms is shown, together 

 with baskets for rearing silkworms, chains 

 of cocoons, and pigeon-holes for rearing iso- 

 lated worms. Methods of sterilization are 

 illustrated by the first model of the Chamber- 

 land autoclave used in Pasteur's laboratory, 

 and by Chamberland filters. Virulent diseases 

 are illustrated by the flask of putrified blood 

 from which Pasteur obtained the anaerobic 

 microbe which he called the ' vibrion septique.' 

 U-shaped tubes from Pasteur's laboratory con- 

 taining anthrax blood, with samples of the first 

 and second vaccines against anthrax as sup- 

 plied to veterinary surgeons are exhibited. 

 Down to January 1, 1900, in France alone, 

 4,971,494 sheep and 708,980 cattle have been 

 inoculated. Some manuscript notes by Pasteur 

 on the experiments in his laboratory in 1881 on 

 hydrophobia are shown, as are also his platinum 

 spatula instruments for trephining rabbits and 

 to remove the spinal cord, dried cords, etc. 



On the right-hand of the Salon Pasteur is a 

 model of the Pasteur Institute, with the re- 

 cently completed Annexe of Biological Chemis- 

 try and hospital for hydrophobia and diphtheria 

 patients. An adjacent glass case contains a 

 bouillon culture of the bacillus of diphtheria in 

 a large flat-bottomed flask, the trocar of Roux 

 and Nocard with rubber tube to collect the 

 blood from the immune horse, the jar in which 

 the clot and serum separate ; a small filter by 

 L. Martin for experiments on the toxin, the 

 large filter used to filter the cultures of diph- 

 theria to prepare the toxin, the filtered culture, 

 and bottles of the serum in liquid and dried form. 



On the left-hand side is the exhibit of the 

 Pasteur Institute at Lille, showing cultures of 

 the plague bacillus of Yersin-Kitasato and the 

 antiplague serum ; venomous snakes, with Cal- 

 mette's serum against snake bite ; the steriliza- 

 tion of water by ozone, with numerous maps, 

 plans and photographs of the Lille Institute. 



