(37) Jannasch, P. and Zimmermann; Ber. 39 (1906), 196; Jannasch, P.; Ber. 39 (1906), 3655; Jour. Prakt. Chem. 78, ii. (1908), 28.

(38) Hager; Zeit. Anal. Chem. 10 (1871), 341.

(39) Baubigry, M.; Compt. rend. 146 (1908), 335, 1097.

(40) Sammet; Zeit. Physikal. Chem. 53 (1905), 684; Jour. Chem. Soc. (1906), ii., 153.

41) Bray, W. G. and Mackraj, G. M.; > Jour. Amer. Chem. Soc. 32 (1916), 1193. 42) Stepanow; Ber. 39 (1905), 4056. 43) Gooch, F. A. and Perkins, C. C.: Amer. Jour. Sci. (IV.) 28 (1909), 33; ibid (IV.) 29 (1910), 38.

(44) Lasala, E.; Anal. Fis. Quim 17 (1919), 85; Jour. Chem. Soc. (1919), ii., 239.

General Notes.

FRACTIONAL HORSE-POWER MOTORS: A BRITISH

ACHIEVEMENT.

The Board of Trade Journal states that before the war the manufacture of fractional horse-power motors was almost exclusively a Continental and American enterprise, and the British market usually satisfied its needs from foreign sources. Within the last few years there has developed, however, a British industry which has already succeeded in capturing a large part of the home market for these motors and looks forward to a substantial overseas trade in the near future.

The applications of the electric motor of fractional horse-power are many and various; sewing machines, vacuum cleaners, washers, machine tools. letter copiers: these and a hundred others used in the home, workshop, or office are being driven by motors of small size of one-fourtieth h.p. upwards.

ROYAL INSTITUTION.

A General Meeting of the members of the Royal Institution was held on Monday afternoon, November 3, Sir James CrichtonBrowne, Treasurer and Vice-President, in the chair.

The special thanks of the members were returned to Sir Alfred Yarrow for his generous donation towards the cost of advertising the lectures, and to Mr. Archibald D. Fox for his gift of Michael Faraday's Penknife.

The Chairman announced that the Christmas Lectures this year would be delivered by Frank Balbour Browne, Lecturer in Zoology (Entomology) in the University of Cambridge, the subject being "Concerning the Habits of Insects.

Mr. A. O. Trencham was member,

elected a

SCIENTIFIC TEST IN SMOKELESS
FUEL PRODUCTION.

The Department of Scientific and Industrial Research has issued an interesting report on the experiment carried out by the Research Board in July, 1924. The test was made on 92 tons of Dalton main coal.

During the test, which those responsible consider was carried out satisfactorily from the technical point of view, samples were taken of the coal and of the products of carbonisation, and the conditions of working and the labour required were carefully oted. The samples collected were all reduced as far as possible and brought to the Research Station for examination. The yields of products per ton of coal carbonized were as follows:

Coke, 13.92 cwt.

Gas, 5,620 cu. ft., or 39.6 therms.
Tar, 18.62 gallons.

Liquor, 26 gallons.

Crude spirit, 1.78 gallon.

Ammonium sulphate, 13.55 lb.

The coke or smokeless fuel produced was, it is stated in the official summary at the end of the report, of a very suitable size (lin. to 2in. pieces). It was not friable, and contained only 4.6 per cent of breeze. Analysis showed that it contained rather a low percentage of volatile matter (approximately 4 per cent.). When burnt in a household grate it was readily ignited and gave a good hot fire. The fire showed less flame than the coke cakes as manufactured at the Research Station, as was to be expected from its low content of volatile matter.

The yield of tar was high, representing 68 per cent. of that obtained in the assay apparatus. On examination this tar proved to be a normal low-temperature tar. The yield of gas was fairly high, and throughout the test varied considerably both in volume and in calorific value, owing to variations of pressure in the hydraulic main. The yield of ammonia was also fairly high. The liquor was, however, less than 6oz. strength, and it is questionable whether so dilute a liquor would justify recovery. The spirit obtained by scrubbing the coal gas amounted to 1.78 gallons per ton of coal.

SCIENCE AND LIFE ASSURANCE.

Science enables the great beneficent work of Life Assurance to be conducted on safe and sound lines. One of the most, if not the most, important officials connected with a life office is the actuary, and then there is the doctor, whose work in eliminating bad risks is of far reaching importance. Great Britain is the home and the pioneer of modern Life Assurance. The British Assurance Offices have a world-wide reputation for soundness, for safe management, and for fair dealing in the carrying out of its sacred trust, namely the protection of the family in the time of need.

Some of the offices have latterly branched out in other directions, such as the Wesleyan & General Assurance Society, of Birmingham, which some time ago established a Health Bureau in an effort to still further prolong life, and it is reported that considerable success has rewarded the Society's efforts in this direction. We might mention that while Great Britain can justly claim to be the pioneer of modern Life Assurance, the United States can with equal justice claim to be the pioneer of Health Service in connection with Life Assurance, one large company, the Metropolitan, of New York, having spent vast sums on its Free Health Service during the past ten years, and so successful has this department been, that, owing to the prolongation of the lives of its policyholders, the venture has proved in all respects a financial success-an instance of virtue bringing its own reward.

CHEMISTRY AND WAR.

In the Great War, and especially towards

its conclusion, Chemistry played a great part in bringing the world conflict to a triumphant issue. Chemistry is sure to play a predominant part in the next war, let it be soon or late. In connexion with a joint dinner of the Society of Chemical Industry and the Chemistry Industrial Club, at the Hotel Victoria, London, on November 14th, the subject was adverted to by several speakers.

Sir Richard Glazebrook said this country owed its present safety in no small degree to Lord Moulton and those who worked with him in suppying our troops with explosives, and to those chemists who, when called upon, were able to provide protection against the gas attack of the enemy. As to the future, though gas warfare was a hateful crime, he agreed entirely with Professor Smithells that there could be no halfmeasures of defence, so long as was was possible. It would be dangerous in the highest degree, it would be criminal, if the Army did not put itself in a position to deal with the kind of warfare which the most competent judges of this and other countries believed to be the warfare of the future. gain security England must appeal to her chemists.

To

filled with atmospheric air at reduced pressure, and are excited by high-ferquency currents. In addition, he employs phosphorescent materials and pigments, either applied to the tubes or incorporated in the glass, to modify the effects. He finds a definite relation between the pressure in the tube and the character of the light emitted, and by suitable adjustments he obtains rays lying between the rose and the violet of the spectrum, without green or red.

After the current has been cut off from them his treated tubes continue to glow, though with diminishing brightness, for a period said to be about equal to that for which they have been excited. Those brought to London are only small---8 mm. in internal diameter and requiring for their excitation a current one-tenth of a milliampere at pressure of 6,000 volts and of frequency in the neighbourhood of 1,000,000.

DEPARTMENT OF OVERSEAS TRADE.

In view of the probable re-opening of the British Empire Exhibition in 1925, it has been decided to suspend the London Section of the British Industries Fair which would otherwise have been held from the 16th to 27th February. The Birmingham Section of the Fair will, however, be held as usual, and as a special measure for 1925 only, the Birmingham authorities have generously undertaken to organise sections in their Fair for those exhibitors who have hitherto shown in London, provided that the demand for space ensures the adequate representation of the industries concerned. The Department of Overseas Trade expects to resume the series of British Industries Fairs in London in 1926.

FRACTIONAL HORSE-POWER

MOTORS.

We touch on this question in another column and are pleased to learn that a list of United Kingdom manufacturers of fractional horse-power motors may be obtained by persons interested on application to the Department of Overseas Trade, 35, Old Queen Street, London, S.W.1.

MORE WORK FOR BRITISH FIRMS. The Municipality of Copenhagen have placed another large order for Water Tube Boilers with the Vickers-Spearing Boiler Co., Barrow-in-Furness. This is the second contract the Municipality has placed with this Company recently.

Liquid Chlorine.

It is only within recent years that Liquid Chlorine has been available for commercial purposes, the first plant in this country for the liquefaction of chlorine having been erected by The Castner-Kellner Alkali Co., Ltd., in 1909.

Liquid Chlorine is now delivered in quantity to any part in steel cylinders or tank wagons. It is dry and pure, and does not suffer deterioration in storage, so that it is now used in any convenient place to carry out chlorinations which were impossible a short time ago, when chlorine was available only in the form of its compounds or as a moist impure gas.

The liquid can be handled quite easily without risk, provided the necessary precautions are taken.

Liquid Chlorine boils at -33.6° at 760 mm. It is a dark greenish yellow liquid which solidifies at -102° C. to a yellow crystalline mass.

USES OF LIQUID CHLORINE.

The uses of Liquid Chlorine include the preparation of bleach liquor, the production of metallic chlorides, the manufacture of dyestuff intermediates and of non-inflammable solvents, and sterilisation.

Considerable quantities of liquid chlorine are used by bleachers and paper-makers in the preparation of bleach liquor. Bleach liquor is prepared by dissolving bleaching powder in a vat which is provided with an agitator. Calcium hypochlorite, the bleaching agent, is formed in the solution, leaving a sludge which consists essentially of lime mud and occasionally lumps of bleaching powder. This sludge, even after washing, carries away to the dump an appreciable quantity, frequently as much as 10 %, of the available Chlorine."

The recent practice of using liquid chlorine in conjunction with bleaching powder in the preparation of bleach liquors has shown that there is an improved dissolving of the bleachpowder, the lumps are broken down, the lime sludge and the chlorine react to produce more bleaching liquor, and the volume of the sludge remaining is only 25 %, or less, of that obtained by the old method. (Fig. 1.) Moreover, the percentage of available chlorine in this sludge is very much less than that in untreated sludge. In addition, the bleach liquors produced are stronger.

MINERALOGICAL SOCIETY. November 4.-Dr. H. H. Thoma, and afterwards Prof. W. W. Watts in the chair. DR. M. S. KRISHMAN: Note on Cordierite

in a cordierite-gneiss from Madura District, Madras, India.

Optically positive cordierite occurs in an Archaean gneiss produced by the metamorphism of biotite-gneiss by an intrusive tongue of charnockite. The associated rocks are crystalline limestones (with lime-silicate minerals), and gneisses containing felspars, garnet, sillimanite, biotite, and titanoferrite. Cordierite from two other localities in Penin

sular India (Vizagapatam and Travancore) is also known to be optically positive. This positive character is suggested to be due to the isomorphous replacement of MgO by FeO, as in the rhombic pyroxenes, olivines,

etc.

DR. A. BRAMMALL: Lime as a constituent of certain important rock-forming minerals: Its behaviour relative to that of other bases of RO type.

A review of the facts governing the extent to which RO-bases replace each other in rock-forming minerals, special reference being made to the anti-pathetic relationship between lime and magnesia as constituents of the same simple molecule.