474 



NATURE 



[March 19, 1885 



I. Glucinum Chloride 



Substance Displaced CO, t d 



Experiment i. ... 26-4mgrms. ... 7-47 c.c. ... 635°... 2733 

 ii. ... 28-0 „ ... 7-98 ,, ... 785 ... 2714 

 The theoretical density of G1"CI„ is 276, and this formula, 

 therefore, represents the molecule of this compound. 



II. Glucinum Bromide 



Substance Displaced CO- t ,/ 



"Experiment ii. ... 35'gmgrms. ... 4'2Sc.c. ... 608 ... 6-487 



,, iii. ... 6i-i ,, ... 7-53 ,, ... 630°... 6-276 



,, iv. ... 26-0 ,, ... 3-22 ,, ... 606°... 6-245 



The density of Gl"Br., is 5 84, and that of Gl'"Br 3 is 8-76. The 

 agreement in this case is not so close as in the case of the 

 chloride, but is sufficiently near to show that the true molecular 

 formula is Gl"Br„, and not Gl'"Br... Thus, the vapour-density 

 of both compounds necessitates the atomic weight 91. The 

 result is a striking argument in favour of the value of deductions 

 drawn from the periodic law in regard to the atomic weight of 

 an element, and shows that such deductions will in future form 

 one of the most important factors in fixing a doubtful atomic 

 weight. The author did not appreciate the full value of the 

 periodic law when he wrote his former paper, otherwise he would 

 probably have stated his conclusions less positively. 



Zoological Society, March 3. — Prof. W. H. Flower" 

 F.R.S., President, in the chair. — Dr. E. Hamilton made some 

 remarks on the supposed existence of the Wild Cat {Felix catus) 

 in Ireland, as stated at a former meeting, observing that there 

 was no record of the Wild Cat being indigenous to that country. 

 Dr. Hamilton believed that the cat shown at the meeting in 

 question was only the offspring of domestic cats horn and bred 

 in the woods of that district. — A letter was read from Mr. J. 

 H. Thomson, C.M.Z.S., giving the locality of Helix (Hemitro- 

 clius) filieosia, which had been previously unknown. — Dr. A. 

 Giinther, F. K.S., exhibited and made remarks on the skin of 

 a singular variety of the Leopard which had been obtained in 

 South Africa. The back in this specimen was black, and the tail 

 reddish gray, while the usual characteristic spots of the ordinary 

 leopard were nearly altogether absent. — Mr. H. H. Johnston, 

 F.Z. S., gave a general account of the principal animals observed 

 by him during his recent journey to Kilimanjaro and his stay on 

 that mountain. — Mr. Oldfield Thomas read a report on the 

 Mammals obtained and observed by Mr. Johnston during his 

 expedition. — Capt. G. E. Shelley read a report on the birds 

 collected by Mr. H. H. Johnston in the Kilimanjaro district. 

 The collection contained examples of fifty species, six of which 

 were believed to be new to science. — Mr. Charles O. Water- 

 house read a paper on the insects collected on Kilimanjaro by 

 Mr. H. PI. Johnston, and gave the descriptions of six new 

 species of Coleoptera, of which examples occurred in the collec- 

 tion. — Prof. F. Jeffrey Bell read a description of a Nematoid 

 Worm (Carditis vermcosus] obtained by Mr. Johnston on Kili- 

 manjaro, which was found to be parasitic on a species of Mantis. 

 — Mr. E. J. Miers communicated the description of a new variety 

 of River-Crab of the genus Thelphusa (T. depressa, Krauss, var. 

 Johnstoni), which had been obtained by Mr. H. H. Johnston 

 in the streams of Kilimanjaro. — Mr. Francis Day read the 

 fourth of the series of his papers on races and hybrids among 

 the Salmonidfe, continuing the account of the Howietown ex- 

 periments from November, 1884, to the present time. — Prof. 

 Ray Lankester read some notes on the heart described by Sir 

 Richard Owen in 1841 as that of Apleryx, and came to the 

 conclusion that the heart in question was that of an Omitho- 

 rhynclius. 



Chemical Scciety, February 19. — Dr. W. H. Perkin, 

 F.R.S., President, in the chair. — The President announced that 

 Mr. Warren de la Rue, F. R. S., had presented a bust of the late 

 Prof. Dumas. The following papers were read : — On benzoyl- 

 acetic acid and some of its derivatives, part 2, by Dr. W. H. 

 Perkin, jun. — On toughened filter-paper, by E. E. H. Francis. 

 — The detection and estimation of iodine, by Ernest H. Cook, 

 B.Sc. (Lond.). — Note on methylene chlor-iodide, by Prof. J. 

 Sakurai. — A quick method for the estimation of phosphoric acid 

 in fertilisers, by J. S. Wells, Columbia College. — On the 

 luminosity of methane, by Lewis T. Wright, Assoc.M.Inst.C.E. 

 — On the oxides of nitrogen, by Prof. W. Ramsay and J. Tudor 

 Cundall. In this research it is shown — (1) That the green or 

 blue liquid obtained by the action of arsenious anhydride on 

 nitric acid consists of a mixture of nitrous anhydride and nitric 



pei oxide, in proportions depending on the strength of the nitric 

 acid and the temperature at which the volatile liquid is con- 

 densed. (2) That if a dehydrating agent, such as sulphuric acid, 

 be present in sufficient quantity the distillate consists of pure 

 peroxide, and that this process is by far the most convenient one 

 for the preparation of the peroxide. (3) That if oxygen be passed 

 over the blue liquid, the vapours condensed in a freezing mixture 

 are still blue or green ; a great excess of oxygen is necessary to 

 effect conversion from nitrous anhydride into peroxide. (4) That 

 when excess of nitric oxide is passed along with the peroxide 

 into a cooled bulb, the trioxide is produced, the amount of tri- 

 oxide depending on the temperature of the condenser. (5) Vapour- 

 density of a liquid of a deep blue colour, containing about 30 per 

 cent, of trioxide and 70 per cent, of peroxide, shows that the tri- 

 oxide cannot exist in the gaseous state, but at once dissociates into 

 nitric oxide and peroxide on changing to gas. The theoretical 

 vapour-density of such a mixture was calculated from a formula 

 deduced from the second law of thermodynamic; by I. Willard 

 Gibbs, which shows the relations between temperature, pressure, 

 and vapour-density of the mixture of NO, and N /)., in the 

 gaseous peroxide ; and it was found that the vapour-densities of 

 a mixture of (NO s + N 2 4 ) (partly present in the original 

 liquid as peroxide, partly formed by the decomposition of the 

 N„0 3 present into NO and (NO„ + N„0 4 ) ) with the NO pro- 

 duced by the decomposition of the N.,0 3 , calculated by means 

 of Gibbs' formula, are identical, within limits of experimental 

 error, with those obtained by direct experiment. (6) The 

 presence or absence of moisture does not appear to affect the 

 reaction between NO and 2 . (7) It is probable that N„0 3 

 undergoes dissociation with rise of temperature, even while 

 liquid. — Discussion : — Dr. Armstrong said that he had listened 

 to the paper with great interest, as- he had made numerous 

 experiments en the subject, and had long been of opinion that 

 N»0 3 did not exist, at all events as gas. The authors' observa- 

 tions, whereby they were led to this conclusion, were of con- 

 siderable importance, and it was to be hoped that ere long con- 

 firmatory evidence that would more directly appeal to chemists 

 would be forthcoming. It was noteworthy that there was no 

 recorded evidence proving the existence of N„O s as gas. Gay- 

 Lussac's experiments, published in 1S16, showed that nitric 

 oxide and oxygen only reacted in the proportions to formN L ,0 4 , 

 and that reactions in proportions corresponding with the produc- 

 tion of N 2 3 only took place in presence of alkali. The method 

 adopted by the authors did not suffice to prove the existence of 

 N s 3 , even as liquid, and the results could be equally well 

 interpreted on the assumption that they were dealing with a 

 solution of NO in N 2 4 . It was to be expected that N„0 4 would 

 be a good solvent of NO, as it appeared to be the rule that 

 bodies which are related are easily miscible, phosphorus, for 

 example, being very soluble in PC1 3 , and sulphur in CS« and 

 SX'l.,. One observation made by the authors did, however, 

 support their view, viz. the observation that the blue liquid was 

 with great difficulty oxidised by passing oxygen into it. In all 

 his experiments. Dr. Armstrong had found that the reactions 

 attributed to N„0 3 could be equally well affected by a mixture 

 of N.,0 4 and NO. As to the action of arsenious oxide on nitric 

 acid, in his opinion, nitrous acid was the product, and the 

 manner in which this underwent change entirely depended on 

 the conditions. In dilute solution, NO would be produced in 

 accordance with the equation: 3HNO„ = 2NO + HN0 3 + H 2 ; 

 but in presence of nitric acid the reaction HNO„ + HN0 3 = 

 N„0 4 +H„0 would take place, and would more and more 

 preponderate the less the amount of water present. The addi- 

 tion of sulphuric acid would of necessity favour the latter mode 

 of change. When N.,0 4 is passed into sulphuric acid, nitrosyl 

 sulphate and nitric acid are formed ; in presence of NO the 

 latter is reduced to nitrous acid which also forms nitrosyl 

 sulphate with the sulphuric acid, so that a mixture of NO and 

 N„0 4 in proper proportions precisely acts as though it were 

 N s 3 . 



Anthropological Institute, March 10. — Francis Galton, 

 F.R.S., President, in the chair. — The election of G. F. Legg 

 was announced. — Mr. James G. Frazer read a paper on certain 

 burial customs as illustrative of the primitive theory of the soul. 

 The Romans had a custom that when a man who had been 

 reported to have died abroad returned home alive, he should 

 enter his house, not by the door, but over the roof. This custom 

 (which is still observed in Persia) owed its origin to certain 

 primitive beliefs and customs with regard to the dead. The 

 ghost of an unbmied man was supposed to haunt and molest the 



