118 



CHEMISTRY. (BACTERIOLOGICAL CHEMISTRY.) 



are more stable the higher the atomic weight; 

 2. that in the odd series they are less stable the 

 higher the atomic weight. The author then pro- 

 re ;-ils to consider the extent to which the vari- 

 ous elements combine with oxygen, and draws 

 the conclusions : 1, That in the even series the 

 higher the atomic weight the greater is the 

 tendency to combine with oxygen; and, 2, that 

 in the odd series there is little tendency to form 

 peroxides, but such as exist show that the tend- 

 ency to form such oxides decreases as the atomic 

 weight rises. He is of opinion that the dia- 

 metrically opposite bearing of the odd and even 

 series in regard to the stability of the oxides is 

 an indication that the attraction for oxygen is 

 influenced by the magnetic state of the elements, 

 those of the even series being usually regarded 

 ;is paramagnetic, and those of the odd series as 

 diamagnetic. 



The atomic weight of palladium has been re- 

 vised by Prof. Keiser and Miss Breed. Prof. 

 Keiser, in 1888, from palladium diammonium 

 chloride deduced the value 106-27. Since then 

 three other determinations by Bayley and 

 Lamb, Keller and Smith, and Joly and Leidie 

 have given discordant results. Prof. Keiser 

 found a compound palladium dichloride which 

 could be vaporized and therefore subjected to 

 fractional distillation a method considered by 

 Stas the only one by which substances may be 

 obtained in the highest state of purity. Work- 

 ing from this, he obtained values closely agree- 

 ing with one another, the mean of which was 

 106-25. 



The atomic weight of barium has been very 

 carefully estimated by Prof. Richards, of Har- 

 vard University, on the basis of analyses of the 

 bromide and the chloride. The concordance of 

 the large number of individual experiments, the 

 highest and lowest mean values in 50 separate 

 determinations differing by only T jfo, commends 

 his result*. Taking oxygen at 16, the atomic 

 weight of barium, finally estimated from these 

 determinations, is 137-43. The experiments with 

 barium chloride afforded a means of independ- 

 ent ly ascertaining the atomic weight of chlorine. 

 The number thus obtained is 35-457, identical 

 with the value given by Stas. 



In their redetermination of the atomic weight 

 of molybdenum, E. F. Smith and Philip Maas 

 employed a method by the action of hydrochloric- 

 Jicid gas upon molybdic acid and molybdates 

 (sodium molybdate was used). Molybdenum 

 hydrochloride and sodium chloride were the re- 

 sult of the action. The atomic weight of molyb- 

 denum was calculated from the quantity of 

 ^odium chloride the values of oxygen (16), 

 sodium, and chlorine being taken from Clarke's 

 n-vi>.'(l tables, October, 1891 as 96-08. 



In his observations on the ratio of the atomic 

 weights of hydrogen and oxygen, Prof. Julius 

 Thomson, in order to avoid the errors incidental 

 to the direct methods of estimating the ratio, 

 employed an indirect method, which consisted 

 i-i estimating the. ratio of the molecular weights 

 of hydrogen, chloride, and ammonia. His re- 

 sults led to the conclusion that 1 : 10 represents 

 the value of the ratio II : (), with ;in accuracy as 

 great as is warranted by the numbers in use for 

 the atomic weights of chlorine and nitrogen. 



A. E. Tutton has shown that all the crystal- 



lographical properties of the strictly isomor- 

 phous rhombic normal sulphates of potassium, 

 rubidium, and caesium are functions of the 

 atomic weight of the metal which they contain. 



Describing some experiments in the electrol- 

 ysis of glass, Prof. Roberts-Austen says that, in 

 connection with Mr. Stansfield, he has found 

 that if a bulb of glass be filled with sodium 

 amalgam and immersed in a vessel of mercury 

 heated in a sand bath to over 200 P., on con- 

 necting the sodium amalgam and the mercury 

 respectively with the terminals of a battery, 

 sodium will pass from the amalgam through the 

 glass into the mercury. At the end of the ex- 

 periment the glass is unchanged. If lithium 

 amalgam be substituted for the sodium amal- 

 gam, however, a certain percentage of lithium 

 is found in the glass at the end of the experi- 

 ments, sodium from the glass is driven into the 

 mercury, and the glass is altered in appearance 

 and frangibility. With potassium amalgam and 

 soda glass no change takes place. These phenom- 

 ena are believed by the author to depend on the 

 relative atomic weights and consequent atomic 

 volumes of the elements concerned. Lithium, 

 having a smaller atomic volume than sodium, is 

 able to follow the galleries left by the atoms of 

 the latter metal ; potassium, on the other hand, 

 having an atomic volume greater than sodium, 

 can not force a passage. From the results he 

 has obtained, using other amalgams, such as 

 those of gold and copper and different kinds of 

 glass, Prof. Roberts- Austen hopes to throw light 

 on the formation of mineral veins in rocks 

 which apparently have not undergone fusion. 



Bacteriological Chemistry. The theory of 

 Dr. Uschinsky, that the toxic products elabo- 

 rated by pathogenic bacteria partake of the na- 

 ture of ferments, is supported by the experi- 

 ments of Courmont and Doyon, which go to 

 show that the toxic action of tetanus poison is 

 not hastened by greatly increasing the quantity 

 of toxine introduced into an animal. These in- 

 vestigators say also that they were able to in- 

 duce symptoms of tetanus in animals by simply 

 injecting some of the blood derived from an ani- 

 mal rendered tetanic by their applications. 

 Similar results were obtained with muscle ex- 

 tract. That the quantity of the toxine intro- 

 duced into the system of an animal does not 

 influence the ordinary period of incubation 

 characteristic for each variety of animal, was 

 confirmed by experiments made by Dr. Uschin- 

 sky on rabbits : but he failed to confirm the 

 results obtained by Courmont and Doyon from 

 the injection of the blood of animals rendered 

 tetanic. 



In a paper on the chemical and bacteriological 

 examination of soil, with special reference to 

 the soil of graveyards, Dr. James Buchanan 

 Young discusses the results of a series of experi- 

 ments which he has made on samples of vir- 

 gin soils, pure agricultural soils, and soils which 

 have been, and are, used for purposes of inhu- 

 mation. From these results, as judged by the 

 amount of organic carbon and nitrogen present 

 in the various samples, it would appear that soil 

 that has been used for burial does not mate- 

 rially differ as regards the organic matter it 

 contains from pure good agricultural soil. This 

 fact goes far to support the idea that inhu- 



