Oct, 13, 1887] 



NA TURE 



569 



were made by Berzelius (Sg'as), Hermann (88"8), Marignac 

 (90'54). The earlier results were doubtless vitiated by the 

 presence of iron and of the cerite earths, whilst Marignac's 

 ■letermination is Dper. o objection from the character of the 

 salt (potassium i;;rco::;am fluoride) which he used. In the 

 present determination zirconia was prepared from North 

 Carolina zircons by three independent methods. It was 

 dissolved in sulphuric acid, and the sulphate was crystallized 

 out. This salt becomes normal and constant in weight by 

 heating some hours at 400", the temperature at which it begins to 

 decompose being 470°. The relation of zirconium sulphate to 

 zirconia gives a ratio from which the atomic weight is calcu- 

 lated, and, though the work is not complete enough to state the 

 result with accuracy, the value obtained agrees more nearly with 

 that of Marignac. The author proposes to make further deter- 

 minations, using the tetrabromide. 



Torsion Balances, by Dr. A. Springer. — Light frames are 

 made and stiffened by wires or flat bands being tensioned over 

 them. The beam is then firmly clamped to the bands in such a 

 manner that its centre of gravity is above its point of support ; 

 this tends to tip the beam, thus equilibrating the torsional 

 resistance of the fulcrums. We thus have the torsional resist- 

 ance exerted to keep the beam horizontal, and the high centre of 

 gravity fends to tip it out of the horizontal. The adjustment of 

 the position of the centre of gravity is most easily made by 

 having an adjustable poise placed immediately above the centre 

 of the torsional wire. In order to do away with the necessity of 

 alignment of support, a .>-econdary beam is attached to the first 

 in such a manner that both beams tending to tip in ihe same 

 direction remain stationary owing to their having opposite and 

 equal moments. On this principle scales are constructed which 

 can be used on rolling ships, or in buildings where there is con- 

 siderable jarring. In all the " torsion balances " there is per- 

 manence of adjustu-ent, consequently repeated weighings will 

 give like results. Various "torsion balances" were shown 

 illustrating the principle involved, as well as to show how equal 

 sensitiveness can be obtained with any load. 



Integral Weights in Chemistry, by T. Sterry Hunt. — The 

 author maintains the necessity for taking hydrogen as standard 

 of specific gravity, not only for gases, but also for liquids and 

 solids, and thinks that such considerations lead to a comprehen- 

 sion of the physical properties and chemical constitution of 

 chemical substances. 



Action of Light on the Hydi-acids of the Halogens in presence 

 of Oxygen, by Dr. A. Richardson. — HCl and O were mixed in 

 different proportions in bulbs, and exposed forty to sixty 

 days in sunlight, at the end of which time their contents were 

 examined. Free CI was only noticeable when large excess of O 

 was present, and when the gases had not been dried. Similar 

 experiments were made in the cases of HBr and HI. 



The Present Position of the Alkali Trade, by A. E. Fletcher. 

 — The author, in presenting this report, remarked that no report 

 on this subject had been presented to the Association since that 

 of his predecessor in office, Dr. Angus Smith, in 1861. Tracing 

 the general history of the alkali manufacture, he noticed the 

 various improvements which have been carried out in the 

 mechanical details and in the chemistry of the processes, with 

 special reference to the recovery of by-products. The rapid 

 growth of the alkali trade in Germany was shown by a reference 

 to the exports and imports of the product. In Germany this 

 advance is largely due to the adoption of the ammonia-soda pro- 

 cess, a process which in this country has been taken up thus far 

 by only three firms. It was pointed out, however, that the 

 Leblanc process, with certain modifications, was not by any 

 means a forlorn hope ; and the improvements now being worked 

 out by Messrs. Chance, Messrs. Parnell, and Messrs. Gaskell, 

 Deacon, and Hurler were referred to. 



On the Constituents of the Light Oils of Blast-Ftirnace Coal 

 Tar from the Garthsherric ^Ft;r^x, by Watson Smith. — These tars 

 are recovered from the condensation of the gases evolved from a 

 blast-furnace, condensed by means of the process of Messrs. 

 Alexander and McCosh. The various constituents are described, 

 amongst others toluene and xylene, the latter consisting of about 

 70 per cent, metaxylene. Considerable interest was manifested 

 in a specimen of flannel dyed by xylidine scarlet prepared from 

 this metaxylene, being the first dye product ever prepared from 

 the by-products of the blastfurnace. 



A Ne^v Apparatus for condensing Gases by contact with Liquids, 

 by Prof. Lunge. — The apparatus described is of a construction 

 of the " plate column " style, and consists, as the name implies, 

 of a series of perforated plates arranged in column, and made 

 of stoneware. The gases as they rise are thus brought into im- 

 mediate contact with an extensive plane surface of the absorbing 

 liquid. The cooling is not so rapid as with coke towers and 

 similar arrangements, but it is to be borne in mind that the 

 gases pass more slowly owing to the completeness of the contact 

 with liquid. Comparative results were given showing the 

 working relation between this apparatus and others. 



The Extent to which Calico Printing and the Tinctorial Arts 

 have been aj^ected by the Introduction of Modern Colours, by 

 Charles O'Neill. — The author reviewed the state of things in 

 1856, at which time Perkin's aniline mauve was discovered, and 

 showed the effect of the introduction of alizarine colours. It 

 was shown that the demand had not kept pace with the produc- 

 tion, and this had much to do with the unremunerative condition 

 of calico printing. 



The Chemistry of Cotton Fibre, by F. H. Bowman. — It is 

 shown that cotton, in common with all vegetable substances, has 

 for its base cellulose. The opinion is here expressed that, judging 

 from the results of combustion, it consists of a series of bodies 

 not agreeing in all respects with one another. The mineral 

 matter of cotton amounts to about I per cent., and this is con- 

 sidered to form an essential constituent. 



Isomeric Change in the Phenol Series, by O. R. Ling. — The 



.OHs 



Brr 



,/°"\ 



iNO., , , A . 



I - were stated to 



^/ ^NO. , CI, 

 isomers [ ] ^ and | 



\C1/' \Br/ 



have been prepared. The melting-point of the former was found 

 to be 125°, and its calcium salt contained i\ molecules of water, 

 whereas the melting-point of the latter was 117", and its calcium 

 salt contained 7 molecules of water. 



On Methylene Blue and Methylene Red, by Prof. Bernthsen. 

 — In this paper it was shown how from thiodiphenylamine, by 

 respective nitration, reduction, and oxidation, Lauth's violet 

 (thionine) was obtained. Methylene blue was described as 

 tetramethylthioninechloride. 



On the Constitution of Azimido Compounds, by Drs. Noelting 

 and Abt. — The formulae given by Griess and by Kekule for the 

 azimido compounds were explained and discussed, and it was 

 shown that the evidence was in favour of the formula of 

 Kekule. 



Velocity of Formation of Acetic Ether by Prof Menschutkin. — 

 In these experiments acetic anhydride was used instead of 

 the acid by which in his previous work the process of etheri- 

 fication had been effected. It was found that the velocity of the 

 reaction was greater with the primary than with the secondary 

 alcohols, and that it was much slower in the higher members of 

 an homologous series than in the lower. A distinct and marked 

 difference occurs between isomers as shown by the examina- 

 tion of butyl and isobulyl alcohols. By working in solution 

 the reaction proceeds more regularly, and the results agree better 

 amongst themselves. The author finds that the nature of the 

 solvent affects the course of the reaction in such a manner as to 

 throw some doubts on the hypothesis of Guldberg and Waage. 



The Relation of Geotnetrical Structures to Chemical Properties, 

 by Prof Wislicenus. — This memoir — probably the most im- 

 portant contribution that has yet been made to the question of 

 the constitution of unsaturated organic compounds — cannot 

 readily be understood without the accompanying diagrams. The 

 results have already bten published in the Transactions of the 

 Royal Saxon Academy. 



Note on Valency, by Prof. Armstrong. — An attempt to explain 

 the phenomena of valency according to the views expressed by 

 Helmholtz as to the unit charge of the elements and its distri- 

 bution. 



The Solubility of Isomeric Organic Compounds, by Prof. 

 Carnelley. 



(l) For any series of isomeric organic compounds the order of 

 solubility is the same as the order of fusibility, i.e. the most 

 fusible compound is also the most soluble. This is shown to 

 hold true in a very large number of cases, whilst there are very 

 few exceptions, and those of a doubtful character. 



