596 



NA TURE 



{Oct. 18, 1888 



year. The influence of traces of free chlorine and of 

 moisture on the course of the reaction was investigated. 



In connection with the " Report of the Committee on 

 the Properties of Solutions," read by Dr. Nicol, a new 

 apparatus for determining solubilities at temperatures 

 below ioo° was shown. Excellent results had been ob- 

 tained, owing to the very intimate mixture of the salt and 

 solvent. 



Dr. Johnstone Stoney exhibited to the Section a dia- 

 gram illustrating the logarithmic law of the atomic weights. 

 Many curious relations are brought out by its means. If, 

 as seems probable, the logarithmic law be a law of Nature, 

 there appear to be three elements lighter than hydrogen. 

 Prof. Sterry Hunt, in his paper on " The Study of 

 Mineralogy," advocated a system of mineralogy, based 

 on the successive forms which are imposed upon matter : 

 (1) the chemical form or composition ; (2) the minera- 

 logical form, or physical state ; (3) the crystalline form, 

 being the most accidental. 



Some speculations suggested by Van 't Hoff's hypo- 

 thesis were put forward by Mr. J. E. Marsh, attention 

 being drawn to certain compounds, which appear to be 

 geometrical isomers. 



The same author, in another paper, suggested a new 

 constitutional formula for camphoric acid. 



On the Friday morning an interesting and well-attended 

 discussion (at which the members of Section D were 

 present) was opened by Prof. Michael Foster, on the 

 " Chemical Problems presented by Living Bodies." In 

 the course of his remarks he suggested several subjects 

 for chemical investigation, such as the exact chemical 

 difference of certain proteids, the changes which occur 

 in the curdling of milk and the clotting of blood, and, to 

 the biologist, the all-important question of the relation 

 in which water stands to the organism. 



An animated discussion followed, in which several 

 chemists and biologists took part. In reply to Prof. 

 Thiselton Dyer's question, as to whether the processes 

 employed by chemists had any connection with those 

 which take place in Nature, Prof. Armstrong cited several 

 cases in which the chemical changes occurring in Nature 

 bore a suggestive relation to those brought about in the 

 laboratory. 



In their paper on the " Incompleteness of Combustion 

 on Explosion," Prof. H. B. Dixon and H. W. Smith show 

 that, on exploding a mixture of oxygen and hydrogen in 

 a long tube, a considerable residue of gas is obtained, 

 which is still explosive. Experiments were made to arrive 

 at the cause of the phenomenon, and an explanation is 

 suggested. 



A new gas-analysis apparatus was shown by Dr. Nicol, 

 which combined the advantages of the Hempel appar- 

 atus with the means of using mercury and of readily 

 performing explosions. 



Dr. Bott exhibited a modification of a vapour-density 

 apparatus, previously described, which can be employed 

 at any temperature or pressure. 



On the Saturday morning Prof. Dunstan read the 

 u Report of the Committee on the Teaching of Chemistry,'' 

 which was followed by a paper on " Chemistry as a School 

 Subject," by the Rev. A. Irving. 



In the ensuing discussion, which was confined to the 

 teaching of chemistry in schools, many of the speakers 

 seemed to agree with the opinions quoted in the report, 

 viz. — 



(1) That chemistry should be taught in schools, 

 first, and mainly, on account of the mental training it 

 affords ; and, secondly, for the sake of it's applications, 

 and its direct bearing on the facts of every-day life. 



(2) The chief difficulties met with in teaching seem to 

 be those which arise from (i.) defective organization and 

 considerations of expense ; (ii.) the lower value attached 

 to chemistry in comparison with other subjects of the 

 school curriculum ; (iii.) the time which is devoted to the 



subject ; (iv.) preparation for various examinations ; (v.) 

 absence of good text-books ; (vi.) dearth of properly- 

 qualified teachers. 



(3) The older plans of teaching are felt to require 

 modification. 



The Committee ask for reappointment. 

 A discussion on " Valency" was opened on Monday by 

 Prof. Armstrong. The question of constant and variable 

 valency was referred to in connection with such com- 

 pounds as chloroplatinic acid, &c, and a few new terms 

 were introduced. The constitution of such bodies as 

 tetra-methyl-ammonium iodide was considered. Dr. 

 Morley drew attention to the influence which one element 

 in a compound often has in modifying the properties of 

 another not immediately adjacent to it. Chemists were 

 advised to study the facts connected with the question 

 carefully before speculating. 



Later on, Mr. Veley described an ingenious arrange- 

 ment he had invented for studying the action of acids on 

 copper, under simple conditions. 



The closing sitting was opened by Prof. Armstrong, 

 who read the "Report of the Committee on Isomeric 

 Naphthalene Derivatives." It was shown that the exist- 

 ence of all the known dichlor-naphthalenes can only be 

 explained by the use of space-formulae. 



In a " Note on the Molecular Weight of Caoutchouc 

 and other Bodies," Dr. J. H. Gladstone and W. J. 

 Hibbert attempted to apply Raoult's method to the 

 determination of very high molecular weights, with fair 

 results. 



. Some interesting compounds of silicon with thio- 

 carbamide and with aniline were exhibited and described 

 by Prof. Emerson Reynolds, together with several other 

 new thio-carbamide compounds. An account of these 

 exhibits was given in Nature last week (p. 575). 



Dr. Richardson, in his paper on " The Action of Light 

 on Water-colours," drew attention to the very important 

 part played by moisture in assisting their decomposition. 

 Colours are divided into two groups : (1) those which 

 bleach under the combined influence of light, air, and 

 moisture ; (2) those on which light exerts a reducing 

 action, which is independent of the air, and in some cases 

 takes place in the absence of moisture. 



A paper on " Pyrocresols," by Dr. W. Bott and J. B. 

 Miller, was illustrated by specimens of a large number of 

 derivatives of o-pyrocresol, amongst them being two new 

 azo colouring-matters. 



With the reading of this paper the proceedings 

 terminated. 



By the courtesy of several chemical manufacturers in 

 the neighbourhood, the members of the Section were 

 enabled, during the course of the meeting, to visit 

 several works where interesting operations were being 

 carried on. 



GEOLOGY AT THE BRITISH ASSOCIATION. 



THE most important geological work done at Bath this 

 year related to volcanic and earthquake phenomena. 

 Dr. Johnston-Lavis gave an account of the recent eruption 

 in Vulcano, and read the letter which has already appeared 

 in the Times from Mr. Narliau, a deeply interested and 

 much-injured witness of the whole occurrence. The chief 

 features seem to have been the ejection of very large 

 blocks to a great distance— one, measuring 10 yards in 

 length, having been found three-quarters of a mile from 

 the crater — and the occurrence of flames, probably caused 

 by the combustion of sulphur deposits. This paper 

 was illustrated by lantern photographs taken by Dr. 

 Tempest Anderson three months before the event. The 

 latter gentleman also exhibited photographs of Vesuvius, 

 Stromboli, and Etna, showing different phases of eruption. 



