In other words, the simplest member of the d-" methyl" series is the optical antipode of the simplest member of the d." ethyl" series. The assumption which has already been made that similarity of sign in the "methyl" series always indicates similarity of configuration leads to the view that d-methylethylcarbinol is the simplest optically active member of the d." methyl" series. Consequently, 1-methylethylcarbinol is the first optically active member of the d"ethyl" series. We therefore arrive at the apparent paradox that the simplest members of the two configuratively similar series are enantiomorophic forms of the

same substance.

The earlier members of the d." methyl" and d." ethyl " series may be represented thus :

third member of this series.

The view here advanced is confirmed by reference to the curves of Pickard and Kenyon (Trans., 1913, ciii., 1924, 1926, 1929). The curves in Figs. I and 2 for the molecular rotations of the d." ethyl series show a marked abnormality in the case of the first member. If the value for 1-methylethylcarbinol is substituted for that of the d-carbinol, the curves exhibit much greater regularity. The curve (Fig. 4) for the d." methyl" series shows no abnormality in the first member, for d-methylethylcarbinol has the same configuration as the other d-carbinols of this

series.

Attention may also be drawn to the values for the molecular rotation of the hydrogen phthalic esters of the dextorotatory carbinols, C2H5 CH(OH) R, in ethylalcoholic solution. The value for the rotation of the ester with R = CH3 is [M] D +86-5°, with R=C3H7, [M]D +9'42°, whilst with RC4H9, MD +52.3°. It is evident that the value for the ester of 1-methylethylcarbinol should be compared with those for the esters of the dextrorotatory carbinols of the "ethyl" series (compare Fig. 1, loc. cit.).

The temperature coefficients for the rotations of the two series of d-carbinols are also of interest in this connexion. The specific rotations of the dextrorotatory alcohols of the methyl series (including d-methylethylcarbinol) diminish with rise of temperature (Trans., 1911, xcix., 50), whereas the values for the dextrorotatory carbinols (up to ethyl-nnonylcarbinol) increase with rise of temperature, with the exception of d-methylethylcarbinol. If the view is accepted that l-methylethlycarbinol is the first member of the d"ethyl" series the temperature-rotation curves for the earlier members of this series are similar in character. These considerations show the impossibility of expressing the relative configurations of a series of optically active compounds by the designations d and l.

323. "The Surface Tension of Mixtures. Part I. Mixtures of partly Miscible Liquids and the Influence of Solubility." BY RALPH PALLISER WORLEY.

Experiments were made with the object of throwing light on peculiarities noticed in the surface tensions of weak solutions of some liquids which are only partly miscible with water.

The surface tension was measured by means of the capillary rise method, the liquids examined being aniline, phenol, and isobutyl alcohol. The decrease of the solubility of aniline in water produced by the addition of common salt had the effect of greatly lowering the surface tension, the final value being not far above that of pure aniline. In the case of aniline and phenol the surface tensions of some of the more concentrated solutions rose with increasing temperature, whilst the surface tensions of none of the solutions, not even the weakest, fell normally, that is, similarly to that of a pure liquid. On the other hand, the surface tension of all solutions of isobutyl alcohol fell regularly.

This difference of behaviour has been accounted for by the different behaviour exhibited towards water with increase of temperature. Whereas the solubility of aniline and phenol increases with rise of temperature, the solubility of isobutyl alcohol decreases up to 75°, and then increases rapidly until the critical solution temperature is reached. These results point to the fact, therefore, that the low surface tension of solutions of partly miscible liquids is due to the lack of solubility of the solute. The reason of this is that liquids when near their limit of solubility form solutions which are rather of the nature of colloidal than of true solutions.

324. "The Surface Tension of Mixtures. Part II. Mixtures of perfectly Miscible Liquids and the Relation between their Surface Tensions and Vapour Pressures." By RALPH PAlliser Worley.

A relation exists between the surface tension and the vapour pressure of a liquid. The object of the present research was to find out whether in mixtures of liquids deviations from a general law governing vapour pressures were accompanied by corresponding deviations in the case of surface tensions.

The following mixtures were examined :-(1) Benzene and Ethylene Dichloride.-The surface tensions were found to agree with those calculated from the admixture rule. So also do the vapour pressures agree with those calculated (Zawidski). (2) Carbon Disulphide and Acetone.-The surface tensions were found to be below the calculated values, and the curve to tend towards a

minimum. The vapour pressures are much greater than those calculated, and the curve passes through a maximum. (3) Acetic Acid and Pyridine.-The surface tensions were much greater than those calculated, and the curve tended towards a maximum value. The vapour pressures are much below those calculated, and the curve forms a minimum.

It seems therefore that when a mixture obeys one admixture rule it obeys the other also; when the surface tensions are greater than those calculated the vapour pressures are less, and vice versa.

Additional proof was given by mixtures of benzene and carbon tetrachloride, and the homologous series of alcohols and water.

From experiments with sulphur and carbon disulphide, it appears that the relations hold good for all mixtures. 325. "The Tautomerism of Thioanilides." By PERCY MAY.

Although the thioanilides are usually represented as thioketones, R.NH CS.R', yet in many respects they react as iminomercaptans, RN:C(SH) R'. The methyl derivatives corresponding with both forms were prepared in the case of thiobenzanilide and thioacetanilide, and their absorption spectra were compared with those of the parent substances in the light of Thiele's theory of "conjugated" unsaturated linkings. When thiobenzanilide was sub

(previously described) based on the deviations observed in the additive relations of mixtures of liquids.

S-Methylthiobenzanilide was obtained by the action of methyl sulphate on thiobenzanilide in alkaline solution, and crystallises from aqueous alcohol in colourless needles, melting at 63-64°.

326. "The Determination of Viscosity." By MALCOLM

PERCIVAL APPLEBEY.

In reply to the criticism of Bingham (Trans., 1913, ciii., 959), the author discussed the phenomena of flow in the Ostwald viscometer and the experimental conditions requisite for obtaining accurate determinations.

On the assumption that a pure liquid consists of a colliquids, the molecular spheres of which have equal radií, should be miscible in all proportions. In binary mixtures this mutual miscibility continues until the ratio of the respective radii reaches 1618, when the border line of partial miscibility is reached. When the ratio is greater than this value, the mixture separates into layers, in each of which the distribution of molecules is dependent on the further change in this ratio until it reaches 2'414, beyond which the liquids should be immiscible.

The curves of volume change calculated from densities available for various mixtures of liquids have been drawn, and the molecular volumes deduced from the ascertained complexities are compared with those required theoretically, on the above hypothesis, for their relative solubilities. The molecular complexities found for these liquids differ from those generally accepted, but the corresponding molecular volumes approximate closely to solubility requirements, and render it probable that the intermiscibility liquids is a function of molecular volume and independent of chemical constitution.

has confirmed.

Lead cyanide was decomposed by hydrogen sulphide, and the hydrogen cyanide was led into water through a U tube containing lead cyanide. To remove any traces of hydrogen sulphide from the aqueous hydrocyanic acid, some lead cyanide was added to it, and the solution shaken. As no trace of hydrogen sulphide was present no lead sulpide was formed; but after filtering this solution it was found that it contained a considerable quantity of lead. It was evident that lead cyanide, which is not appreciably soluble in cold water, is soluble in aqueous hydrocyanic acid, and it was expected that this solution would, on evaporation, deposit pure lead cyanide free from

Lead cyanide, even when powdered, appears to be unattacked by concentrated nitric and sulphuric acids in the cold. On adding water to a crystal, the insoluble oxy. cyanide is formed, and the water becomes cloudy.

A weighed quantity of the substance was heated for some hours to 120°; there was no loss in weight.

For the estimation of cyanogen and lead a weighed quantity of the substance was heated in a water-bath in a sealed tube with a weighed excess of silver nitrate and a little nitric acid. The silver cyanide was collected and weighed. The silver remaining in solution was precipitated and weighed as silver chloride, which served as a check on the weight of the silver cyanide. Finally the filtrate was evaporated with sulphuric acid, and the lead sulphate weighed. Two different samples were analysed :—

1. 0.1838 gave 0.1883 AgCN and 0'2137 PbSO4

CN 1990; Pb=79'42.

II. 0.2272 gave 02340 AgCN and 0.2638 PbSO4.

CN- =20'00; Pb = 79°32.

Pb(CN)2 requires CN=20'07; Pb-79'92 per cent. The crystals consisted therefore of lead cyanide having the formula Pb(CN)2.

328. "Contributions to the Theory of Solutions. The Intermiscibility of Liquids." BY JOHN HOLMES.

The relative solubilities of liquids have been correlated with their molecular volumes as ascertained by a method |

The experimental data include densities at 15° of mixtures of isobutyric acid with water, ethyl tartrate with water, and ethyl tartrate with glycerol; also densities at 25° of mixtures of chloroform with n-amyl alcohol and acetone. The critical temperatures of solution were determined for nicotine and water, and for carbon disulphide and ethyl tartrate when mixed in the proportion of I to 2 molecules (liquid) respectively. Volume changes in aqueous ethyl alcohol mixtures are compared with the corresponding differences from the theoretical values for refractive indices.

329. "A Contribution to the Study of the Constitution of the Methyl Pentoses. Part I. The Synthesis of an i-Methyl Tetrose and an i-Methyl Tetritol." By ROBERT GILMOUR.

An account was given of the isolation of an inactive methyl tetrose by reducing dihydroxyvalerolactone with sodium amalgam in acid solution. The free sugar has been prepared, and found to be a strongly reducing pale yellow syrup.

Methyl tetrosazone forms pale yellow needles, melting at 140-142°. Methyl tetrosephenylbenzylhydrazone forms colourless needles, melting at 99-100°. It was shown that the reduction of dihydroxyvalerolactone yields as the main product a methyl tetritol, along with only a small amount of the tetrose. The tetrabenzoyl derivative of methyl tetritol melts at 136-137°. In addition the methyl tetritol has been oxidised by Fenton's method to the methyl tetrose, which was isolated in the form of the phenyl benzylhydrazone.

A racemic brucine salt of the methyltetronic acid was also described (m. p. 180-181°) as well as a dimethoxyvalerolactone (m. p. 59 -60°), which was obtained by methylating dihydroxyvalerolactone.

Further, an account was given of a method which it is proposed to adopt for the preparation of other methyl tetroses, and their importance as a means of determining the constitution of naturally occurring methyl pentoses was indicated.

and Carbonates at High Temperatures.-M. Amadori.

Solubility in the Solid State of Nitrates, Sulphates,

the solid state is either very small or negligible in the cases

-The solubility of sulphates, carbonates, and nitrates in

of the lithium, sodium, and potassium salts. The nitrates crystallise with the carbonates, and with the sulphates in eutectics constituted almost exclusively of nitrate at a temperature only 3-10° lower than that of the solidification of the nitrate. No compounds are formed either at the temperature of solidification nor at a lower temperature between sulphate and nitrate, nor between carbonate and nitrate.-Atti Reale Accad. Lincei, 1913, xxii., No 7.

NOTICES OF BOOKS.

A Dictionary of Applied Chemistry. By Sir EDWARD THORPE, C.B., LL.D., F.R.S. Assisted by Eminent Contributors. Revised and Enlarged Edition. Vol. V. London, New York, Bombay, and Calcutta: Longmans, Green, and Co. 1913

This volume, covering Sodium-Z, brings to an end the last edition of Thorpe's Dictionary of Applied Chemistry. It fully maintains the high standard of excellence which the previous volumes have reached, and contains a number of lengthy articles by authors of world-wide fame. These include, to mention only a few, articles on Spectrum Analysis, by Prof. E. C. C. Baly; on Soils, by Dr. A. D. Hall; Synthetic Drugs, by Dr. Virgil Coblenz; Vegeto alkaloids by Prof. W. R. Dunstan; Vat Dyes, by Dr. E. Knecht; Water, by Dr. P. F. Frankland; and Terpenes, by Sir W. A. Tilden.

The Progress of Scientific Chemistry in Our Own Times. By Sir WILLIAM A. TILDEN, F.R.S., D.Sc. (Lond.), Sc.D. (Dub.), D.Sc. (Vict.), LL.D.(Birm.). Second Edition. London, New York, Bombay, and Calcutta: Longmans, Green, and Co. 1913.

THE author of this book was confronted with a very diffi.

cult task when he was called upon to deliver a short course of lectures to working men, and chose as his subject the progress of chemistry from 1837 to 1897. However, he proved to be more than equal to the occasion, and this book, based upon the lectures, is a triumphant witness to his skill in making a highly technical and somewhat obscure subject clear to readers who cannot be supposed to possess more than a slight acquaintance with the elements of chemistry. In the second edition, while the matter has been brought up to date, the general plan has student and the general reader a clear idea of the growth not been in any way altered, and the book will give the of modern chemical theory.

A Treatise on Chemistry. By Sir HENRY Roscoe, F.R.S., and C. SCHORLEMMER, F.R.S.. Volume II. The Metals. New Editions. Completely Revised by the Right Hon. Sir HENRY ROSCOE and others. London: Macmillan and Co., Ltd. 1913.

THE general plan and arrangement of the original edition of this well-known standard treatise have been preserved in the fifth edition, but the whole has undergone a careful revision. Mr. T. V. Barker has made alterations and additions in the chapter on crystallography, and Dr. Makower deals with recent important researches in radioactivity, while other specialists have rendered assistance to the author in revising and amplifying the text in accordance with modern knowledge.

A Text-book of Physics. By J. H. POYNTING, Sc.D., F.R.S., and Sir J. J. THOMSON, O.M., M.A., F.R.S. Volume I. "Properties of Matter." Sixth Edition. London: Charles Griffin and Co., Ltd. 1913. THE fifth edition of this treatise on physics was issued only a very short time ago, and hence in the sixth edition it has not been found necessary to make any alterations beyond the addition of several important notes. In many respects it is a model text-book for students who, while possessing an elementary knowledge of physics, have not yet reached the stage when they can profitably attack advanced treatises. The text is remarkably clear and the authors' explanations are both lucid and graphic.

Carbon Dioxide Snow. By I. HALL EDWABDS, L.R.C.P., F.R.S. (Edin.), Hon. F.R.P.S. London Simpkin, Marshall, Hamilton, Kent, and Co., Ltd. 1913. THE author of this little book has done much to render the application of carbon dioxide snow more practicable and economical, and he has had much experience in using it

therapeutically. He describes at some length the apparatus employed, and points out the many advantages which the snow possesses over liquid air in dermatology. He also discusses the results produced in the case of different diseases of the skin, &c., and gives a very impartial account of the effects of treatment with the snow. Details of methods of application are included, with illustrations, and allusion is made to all the necessary precautions in handling the material and in after treatment.

The Silicates in Chemistry and Commerce. By Dr. W. ASCH and Dr. D. ASCH. Translated by ALFRED B. THIS book is based on a thesis submitted to the University SEARLE. London: Constable and Co., Ltd. 1913. of Göttingen, and there awarded a prize in 1903 in connection with the Benek Bequest. The thesis has been much enlarged by the insertion of additional confirmatory material, and the translator has also added many explanatory or critical notes. The authors began their thesis with a comprehensive survey of the existing theories concerning the alumino-silicates, and succeeded in showing that all such theories were incompatible with the facts, except one, viz., that the alumino-silicates are complex acids or salts, Although objections can be brought forward to this view, it seemed not improbable that they are only apparent, and the authors claim that their hypothesis regarding the union of the atoms in the anhydrides of the alumino-silicates satisfactorily meets all criticisms. The theory of hexite and pentite rings (rings containing six or five aluminium or silicon and oxygen atoms) is explained, to other complex acids, e.g., molybdic and tungstic acids, and its application not only to alumino-silicates but also is worked out in detail. The constitutions of clays, ultra marines, Portland cements, glasses, &c., are explained on the basis of the theory. The bearing of the hexite-pentite and the authors' hypothesis is undoubtedly very ingenious theory on the question of the constitution of the atom and its extension to a stereo chemical theory are also discussed, and requires careful consideration.

Cement, Concrete, and Bricks. By ALFRED B. SEARLE. London: Constable and Co., Ltd. 1913.

THIS book contains an excellent account of the chemistry of the manufacture of cements, concretes, and bricks. The genetic relations between these three classes of building materials are clearly pointed out, and modern theories re garding the chemical and physical changes which occur in the setting and hardening of cements and the drying and burning of bricks are discussed. The author's knowledge of the scientific aspects of the brick industry and the questions involved in it is unique, and he places his experience and his wide knowledge freely at the disposal of his readers. The book is not intended for the unscientific man, and a good grounding in chemistry is required in o.der that it may be used profitably; it contains many suggestions as to the directions in which fruitful research may be undertaken. Methods of performing tests on concretes and cements and the making of special kinds of bricks are described in detail.

The Employment of Sodium Bisulphite in the Preparation of Plantation Rubber. By C. BEADLE, H. P. STEVENS, and S. MORGAN.

THIS pamphlet contains an article which has been reprinted from the Indiarubber Journal for August 2nd, 1913. The authors describe shortly the tests they have performed with many specimens of rubbers prepared with and without sodium bisulphite; these tests show that on the whole the former are of slightly better quality. Hence the authors consider that the bisulphite should be regarded as a cheap and effective agent for preserving the pale colour of rubber. They have observed that rubbers prepared with sodium bisulphite tend to dry more slowly than other specimens.