end only it would not be completed for eight or nine years. They were of the opinion that if the mines were drained to this level there was a promising future for the industry in the Halkyn District. Mr. J. Dodd appeared for the Halkyn District Mines Drainage Company, and explained the plans of that Company for draining the mines. The Ministry of Munitions holds a mortgage on the company's assets in respect of the advances made in connection with the pumping scheme. The Company, if released from this mortgage, proposes to raise capital to proceed with the further driving of the sea-level tunnel. Mr. Philip Jones, Manager of the Holywell Halkyn Mining and Tunnel Company and Managing Director of the Waen and Lerllyn Mines, Ltd., described the mining operations carried on in the past in the district between Talargoch and Halkyn, and recapitulated the history and financial position of the Holywell Halkyn Tunnel Com. pany. He thought that the Government could most effectually help this district by proceeding with the scheme for the Mid-Flintshire Light Railway by providing cheap electric power from a central station to be erected at Queensferry, and by guaranteeing minimum prices for galena and blende. Mr. Argall, Managing Director of the Nantymwyn Mine, gave evidence relating to the work done by this Company, and referred to the difficulty placed in the way of further development by the shortage of houses in the district. Mr. T. Miller, Manager of the Welsh Van Mine, stated the reasons for the stoppage of work that had occurred there, and explained the plans of his company for the future development of the Van, Nantiage, aud New Castell mines. He advocated the establishment of a Department of Mines, the revision of mining and mineral laws, and the establishment by the Government of a customs works to smelt home-produced ores. Mr. R. R. Nancarrow, Manager of the Lisburne Development Syndicate, Ltd., and the Welsh Mines Cor poration, Ltd., gave evidence respecting developments proposed to be undertaken by these companies and expressed the opinion that there was a promising future for lead mining in this country, He suggested that State aid should take the form of a bonus of 7s. 6d. a foot on all approved development work and of a minimum price for the products got in relation to the increase in mining costs since 1914. He proposed that such assistance should be given for five years. Mr. Horace Boot, of the Aberllyn Mines, Ltd., represented the mines of the Conway Valley. He referred to the difficulties caused by high wages and the shortage of labour, and was of the opinion that help should be given to the industry by the guarantee of a market for blende at a reasonable price, by an amendment of the system of royalties in vogue, and by the establishment of a Department of Mines to investigate and remedy the troubles of the mine owners. Prof. O. T. James, of the University of Manchester, gave the Committee the benefit of the results of the investigations he had recently undertaken for the Geological Survey in the mining district of Cardiganshire and West Montgomeryshire. He expressed the view that new ore bodies could only be opened up in this district by extensive prospecting and development. THE Prince of Wales has forwarded to the Great Northern Central Hospital a cheque for £405 os. 2d., being one-third of the proceeds of the display at the Royal Albert Hall of the film of His Royal Highness's Canadian Tour. The exhibition was arranged by the Canadian Pacific Railway Company, who defrayed all the costs of the production and by desire of the Prince devoted the receipts to three hospitals in which His Royal Highness was taking a specially active interest. PROCEEDINGS OF SOCIETIES. FARADAY SOCIETY. Annual General Meeting, December 15, 1919. THE following Officers and Members of Council were President-Sir Robert Hadfield, Bart., F.R S. Treasurer-Robert L. Mond, F.R.S.E. Council-Dr. J. Allmand; Dr. H. Burns; Prof. C. H. Desch; Dr. J. A. Harker, O B. E., F.R.S.; Cosmo Johns; Harold Moore; Prof. J. R. Partington; Dr. W. Rosenhain, F.R.S.; Sir T. Kirke Rose; Dr. George Senter. Ordinary Meeting, December 15, 1919. Prof. ALFRED W. PORTER, F.R.S., Vice-President, in the Chair. THE CHAIRMAN referred to the loss the Society bad sus- Mr. A. GEORGE TARRANT, B.Sc., A.R.C.S., read a paper on "The Measurement of Physical Properties at High Temperatures." An account is given of experiments made upon refractory perties at high temperatures, particular attention being materials with a view to measuring certain physical propaid to thermal expansion, tensile strength, and thermal conductivity. A very satisfactory appararus for measuring thermal expansion is described, depending upon the relative expansion of the test substance and the graphite sheath in which the substance is heated. A spiral furnace and stressing arrangement, suitable for work up to 180° C., is described, and the results obtained are roughly indicated. Some notes on structural and operational details of the apparatus are given. Lieut. W. A. MACFADYEN, M.C., B.A. (Cambridge), read a paper entitled "An Aspect of Electrolytic Iron Deposition." The experiments detailed were carried out in seeking the best conditions for obtaining thick hard adherent deposits of iron on steel-mechanism parts which had been machined too much, or worn down in a few places, and thus rendered useless, so as to enable the scrapped parts to be replaced in use after treatment. A simple solution of ferrous ammonium sulphate in water was used as electrolyte, the only additions being sulphuric acid, and, later, powdered charcoal. In the cold the best deposits were obtained from concentrated solutions made about o'005 normal with respect to sulphuric acid, the current density being up to 23 amps./sq. ft. From a solution saturated in the cold, heated to 65° C., and made about 0.02 normal acid, excellent deposits were obtained at current densities of up to some 200 amps. ft., whilst metallic iron in rather less suitable form was deposited at the higher C.D. obtainable in the laboratory, namely, about 1000 amps./sq. ft. If iron be deposited direct on to a steel base and the whole subsequently annealed above the A3 point for pure iron, the two become strongly welded together. Subsequent case-hardening is then usually advisable, since the annealed electrolytic iron is very soft. A paper by Mr. J. GUILFOYLE WILLIAMS, B.Sc., A.I.C. (Glasgow), on "The Electrolytic Formation of Perchlorate," was read in abstract by the Secretary. It is pointed out that present practice in the electrolytic preparation of perchlorate uses much higher temperature of liquor, and current density, than is given in tsxt-books. Experiments are given showing that the current effi ciency of the electrolysis is not considerably affected by liquor temperatures up to 60° C. Production of 1 kilo. NACIO4 at this temper ture requires only about 30 K W.H. against about 3.6 K.W.H. for normal practice. During normal electrolysis the liquor is alkaline owing to the presence of sodium hypochlorite; if this alkalinity is kept down by the frequent addition of hydrochloric acid the current efficiency of high temperature electrolysis is improved. Prof. ALFRED W. PORTER, D Sc., F.RS, read a paper on "The Vapour Pressure of Binary Mixtures." In order to remove difficulties in connection with the proof of the Duhein Marguies formula for the vapour pressures of binary mix ures a simplified proof is given which makes clear the extent of the usual approximations in each step of the proof. As an example of the application of this equation the simplest form of the integral obtained by Margules is fitted to the experimental curves of J. Sameshima for acetone-ether mixtures. The fit is almost perfect. Sameshima himself gives an entirely different explanation of the curves depending upon the assumed presence of associated acetone in the mixture-to an amount given by the law of mass action. The chemical interpretation is hardly admissible in view of the fact that no allowance is made for molecular attractions, which must always be present. Margules' simple equation allows for these molecular forces, and it is seen that no auxiliary chemical changes are required. General curves are given from which, the value of the parameter necessary to fit any particular experimental data can be obtained by inspection. Prof. E. H. CAMPBELL (University of Michigan) presented a paper on "The Solution Theory of Steel and the Influence of Changes in Carbide Concentration on the Electrical Resistivity." Baly's force-field theory is applied to the case of the solid solution of the non-ferrous elements in steel. The fundamental concept of this theory is that every molecule of a solute in solution possesses an electro magnet field. If the force fields of any molecules are opened in solution these molecules become "active," and capable of reacting with different forms of energy-for example, producing electrical conductance in an electric field. The resistivity of a solid solution, e.g., steel, is dependent upon the concentration and degree of dissociation of the solutes. NOTES. ROYAL INSTITUTION.-On Tuesday next, January 13, at three o'clock, Sir John Cadman delivers the first of two lectures at the Royal Institution on (1) " Modern Development of the Miner's Safety Lamp." (2) "Petroleum and the War." On Thursday, January 15, Dr. R. R. Terry, Organist of Westminster Cathedral, begins a course of three lectures, with musical illustrations, on "Renaissance Music in Italy and England," and on Saturday, January 17, Mr. Alfred Noyes gives the first of two lectures on (1) " The Anglo-American Bond of Literature." (2) "Aspects of Modern Poetry." The Friday evening discourse on January 16, at nine o'clock, will be delivered by Sir Jainns Dewar on "Low Temperature Studies," and on January 23 by the Hon. Sir Charles Parsons on "Researches at High Pressures and Temperatures." A LIVE ORGANISATION.-"I believe that when we are able to place present-day occurrences in their proper perspective it will be acknowledged that the work of the Industrial League and Council in bringing together employers and workpeople-shop stewards and men of the most varied opinions-bas done something to sink the asperities of the industrial situation, and helped to create an atmosphere conducive to the consideration of the abstruse and difficult problems which emerge in these times." It is with these words that the Right Hon. G. H. Roberts, M.P., Minister of Food, sums up the activities of the Industrial League and Council, which has its headquarters at 66, Victoria Street, London, S. W. 1, and if the December issue of the Journal published by that organisation, which has been submitted to us for review, can be taken as any criterion, then this eulogium from one of England's prominent Ministers can indeed be regarded in no sense as a passing need of approbation but accorded with a full sense of his responsibilities as one entrusted with the guidance of the future destinies of this country, and, as such, is praise with which we should like to associate ourselves. No finer idea could any organisation have than that which animates the members of this rapid y growing important and influential body. Young in years, but old in knowledge and wisdom, embracing as it does among its members all the pioneers of Great Britain's industries and leaders of Trade Unionism, it has within the short space of five years accomplished much, but for the future no limitations can obscure its horizon. Certainly its official Journal can be regarded as a triumph for such a publication, and it is pleasing to note that with its evolution from childhood to sprightly youth the Executive Committee of the League and Council has decided to publish the Journal monthly instead of quarterly as heretofore, as there is no doubt that such a Journal can do ought else than become a power in the dissemi ation of intelligence which must be of inestimable value to both employers and employed. The December issue of the Journal contains full reports of striking speeches dealing with important industrial problems by Viscount Burnham, C.H., Sir Auckland Geddes, K.C.B., M P., the Right M.P., Mr. G. J. Wardle, M.P., and Mr. R. Tootill, Hon. J H. Thomas, M. P., the Right Hon. G. H. Roberts, C.B E., M.P. WE have received from the Comptroller-General of Overseas Trade the "Report on the Conditions and Prospects of British Trade in India." The report has been compiled by Mr. T. M. Ainscough, O. B. E., His Majesty's Senior Trade Commissioner in India and Ceylon The aim of the report is to impress upon British manufacturers and exporters the recent important and far The experimental portion of the paper describes a research on the influence of the decarburisation by means of hydrogen of a series of alloy steels on the electrical resistivity when the metal is in both the annealed and hardened condition. Annealed steels containing considerable amounts of chromium, tungsten, and molybdenum show on decar-reaching changes in the import trade of India, which call burisation a marked increase in resistivity, due to the removal of the carbon from complex carbides and the dissolution of the metals in the iron. The measurements tabulated indicate marked differences in the constitution of the carbides in the various steels, for special efforts and revived methods and organisation on the part of British traders. The Report, which is the first prepared by a Trade Commissioner in India, is divided into five parts, the first of which contains a general survey of the industrial and commercial position obtaining in India immediately prior to and during the war, with particular regard to foreign competition, the development of Indian industries, the attitude of the merchant houses, and the question of manufacturers' branches in India. A detailed examination of the leading import trades, with special reference to the changes in character, volume, and origin of import during the years of war, will be found in the second part; while the third part embodies a review of the methods of representation and distribution in India in particular trades, together with definite recommendations as to the revised methods which might with advantage be adopted by British interests in order to meet the now conditions. The fourth part of the Report treats of the development of Indian industries and its significance, with special reference, firstly, to the opportunities for the employment of British capital and industrial management in the country, and, secondly, to the readjustments which will probably be necessary in some of our export trades as the result of the competition of local industries. Mr. Ainscough, as representative of the Government of the Dominion of Canada in India, analyses in a further part the prospects for the sale of Canadian produce and manufactures in India. The Report contains valuable information regarding the economic position in India, and it is hoped that publicity will be given to its contents. tion. The Directory is pined in seven languages, Enlish, French, Italian, Spanish, Portuguese, Russian, and Japanese, and is thoroughly and carefully indexed. It contains a complete List of the Members, together with their Business and Telegraphic Addresses, Telephone Number, and Codes used. It also contains classified Lists of Chemicals manufactured by each firm. This publication will be of great value to Traders-both Home and Overseas-who desire to purchase Chemicals from British Manufacturers, and will enable them to cmm ini: cate direct with the manufacturer of any particu. r che nical product in which they are interested. The puc per copy is 10s. 61. One or more copies will be forwarded, post free, on receipt of remittance by the Association of British Chemical Manufacturers, 166, Piccadilly, W. 1. MESSRS. JORDAN AND SONS, LTD., Company Registra tion Agents, of 116-117, Chancery Lane, have published a report of the companies registered during the half year just ended, from which it appears that very great activity number of companies and amount of capical the past prevails in the country's trade. It is safe to say that in year will have outstripped all its predecessors. The registrations in the United Kingdom for the second half of the year numbered nearly six thousand, with a capital of about £260,000,000. This huge total is contributed to in nearly equal volume by Public Companies (£135,000,000) and Private (£125,000,000). Taken in classes, Textiles and Clothing represent thirty millions-a not surprising total in view of the fact that most fabrics now sell at four times their pre-war prices-Mines twenty-four millions, Shipping over twenty-two millions, Banks and Finance nearly twenty-two, aud Oil over twenty millions. Motors figure for over eighteen millions, Carriers for nearly five millions, and Engineers for thirteen millions. Food requires fourteen millions, while Drink is satisfied with less than two. Insurance accounts for nearly ten millions, Kinemas for over six. In contrast to these considerable figures, our Educationists may feel disappointed that Schools can show but a paltry £66,500, while Sports attract £575,000. Music does not play a prominent part in London, while in Edinburgh and Dub in it does not play at all. Patent Remedies, too, find no place in the latter capitals, while in London they do not appear to be in great request. Aircraft do not yet seem to have attained popularity with the Company Promoter, and Undertakers and Cemeteries remain unattractive. COAL MINING IN INDIA.- Quite a large number of Com mittees are now sitting in Delhi to consider questions affecting the expansion of industries in India. These are Committees on Coal Production, Purchase of Stores, Sugar Production, and Chemical Services. Meanwhile a summary of a report by Mr. Trehearne Rees, of Messrs. Forster, Brown, and Rees, London, to the Secretary of State, on" Indian Collieries" has been issued here. In the course of his report Mr. Rees stated that one third of the coal in Indian coal mines is at present being lost by bad methods of mining, while three-quarters of a million tons are lost annually by the wasteful power working of col lieries. The proposals contained in the report include the filling in of old workings to enable more complete extraction of coal, large organised schemes for improving conditions of labour so as to settle non-fluctuating labour populations near the mines, central electric power generation an a compulsory non-profit basis, modern cooking and utilisation of by-products, colliery owned sidings and light railways, and briquette manufacturing. Regarding the Assam collieries, Mr. Rees suggests methods for overcoming the sulphuric acid difficulty. He understands that a committee, including those directly interested, will be formed to consider proposals for dealing with the subject after consideration of the report. -Reuter's Trade Service. CANADIAN INDUSTRIES EXHIBITION.-An Exhibition Royal Geographical Society, 5. exclusively devoted to Canadian Industrial enterprises, to be held in June next in London, will be one of the moet interesting and important of all the series of Exhibitions held during 1920. The Exhibition has the support of the Canadian Trade Commission, the Canadian Manufacturers Association, and the Canadian Mission in London. The organisation is in the hands of Mr. H. Greville Montgomery, Promoter of the Building Trades and other successful Exhibitions, who, in company with Mr. Lloyd Harris, of the Canadian Mission in London, recently paid a visit to Canada to personally enlist the support of firms particularly interested in promoting Canadian interests in the World's markets. Already most of the ground floor space at the Royal Agricultural Hall has been definitely allotted to leading firms, the exhibits comprising Grain Elevators, Separators, Pianos, Woodworking Machinery, Tractors, Confectionery, Polishes, Ready made Houses, Furs, Hardware, Steel Products, &c. All information can be obtained from the offices of the Exhibition, 43, Essex Street, Strand, W.C. 2. A FIRST Edition of eight thousand copies of the Official Directory of the Association of British Chemical Manufacturers has been printed and is now ready for publica MEETINGS FOR THE WEEK. Monday, January 12. Tuesday, January 13. Royal Institution, 3. "Modern Development of the "Rail Royal Society of Arts, 3. (Juvenile Lectures). Societies, at the Royal Society, Burlington House). Royal Institution, 3. "Renaissance Music in Italy and Friday, January 16. Saturday, January 17. Royal Institution, 3. "Anglo-American Bond of Literature," by Alfred Noyes. Double Winder Ploughing (continued). A NUMBER of actual experiments were made in the year 1909 and the spring of 1910 to determine the motor capacities required for the Double Winder Ploughing system. According to these observations 14-16 kw. hours were consumed in ploughing 2500 square metres, i.e., nearly two thirds of an acre, to a depth of 20 25 centimetres in moderately heavy ground. When the resistance of the ground became greater, due to rain, 18-20 kw. hours were required, and the highest figures observed on the heaviest ground were from 22-24 kw. hours when the depth of furrow was 37-44 centimetres. The tests were carried out with a five-share reversible plough of 2.2 metres working width. The full capacity of the plough depends on local conditions, and on trials with a plough of the size referred to it was found that with a moderate winding speed of 165 metres per second and a furrow length of only about 400 metres, two acres could be ploughed per hour to a full depth of about 16 in. Similar trials with a three-share plough with an average speed of 16 metres per second and with a comparatively disadvantageous furrow length of only about 300 metres showed that a surface of 1 acres could be ploughed in one hour to a furrow depth of about 16 in. On the basis of these results and a working day of fourteen hours, which is the usual length of a Continental working day in the principal ploughing months, and taking into consideration the delays for changing the transformer wagon, &c., about 23 acres could be ploughed daily, a feat which has been actually accomplished on several estates. It is not possible, of course, to plough every day at the same rate without stopping. In unfavourable weather, and on account of other circumstances, one or other winding wagon may not be moved forward as quickly as is necessary to maintain the above output, and other delays may occur when the connecting cable has to be lengthened or the transformer wagon moved to the nearest connecting point, which has to be done usually about once a day, but in any case the average daily capacity should not be less than 19-20 acres. As only one winding wagon is employed at the one time in the double winder ploughing system, while the motor of the other winding wagon is at rest during this pull, a smaller motor may be employed on this system than in the single winder system for a similar ploughing output. By this means, and by dispensing with one drum and the corresponding plough rope, the total weight of the winding wagon is reduced, or, in other words, for an equal working weight of motor the capacity of the double winder plough is greater than that of the single winder plough. Four workers only are necessary for working the whole double winder ploughing system, viz., two winding wagon attendants and an attendant for the reversible plough, with an ordinary labourer to assist the latter. Reprinted by permission from the Journal of the Royal Society of Arts. 2. Its suitability for large fields. 3. Great surface capacity on the heaviest ground with deep furrows, and with small consumption of current. 4. The possibility of fixing the winding wagons on very sloping ground, which is not possible in the ease of steam ploughs. 5. Smaller wear of wire cable than in the single winder system, because only one wire length is required to cross the field. Single Winder Ploughing.-A complete equipment for single winder ploughing consists of (a) a winding wagon; (b) an anchorage wagon; (c) the haulage cable. (a) The winding wagon for single winder ploughing carries the electric motor with its control apparatus, the gearing, and the haulage cable drums. The weight of a wagon without wire cable or electric cable is about 13.500 kgrms. (13.3 tons), and the wagon is de signed for a maximum pull of 4000 kgrms. (39 tons). Some dimensions of this wagon are given in the following table :Length. Width Height. Metres. Metres. Metres. The wheels are of ample dimensions to suit farming operations, and permit of safe and easy movement of the winding wagon even on soft wet ground, and also to provide the necessary stability. The electric motor is of the standard rainproof type, and the entire wagon is protected by a roof, the sides being open to give an unobstructed view, which is necessary with this system. A locked protecting cover can be provided for the driving gear, and when this is fitted a standard plain type motor may be used. The size of the winding wagon is such that motors of from 60 90 h.p. output can be used, and a ploughing set has recently been put on the market fitted with a motor of an output of 40 h.p. The power is transmitted, as in the case of the double winder wagon, from the motor shaft to the gearing by means of pulleys and belts, and the remarks made as to electrical and mechanical control gear and safety devices, the advantages of belt drive, &c., in describing the double winder wagon apply here also. Generally, the construction of the winding wagon for the single winding wagon system is similar to that for the double winding wagon system, but the mechanical gear for the single winding system is more complicated, since two cable drums are in use, the direction of rotation of which must be alternately changed. In the type of wagons described, the toothed gear-wheels, rope drums, and ma n bearing housings are made of the best cast steel, and the shaft and axles of Siemens-Martin steel. The changeover two-speed gear enables the reversible plough to be hauled either at the moderate speed of 11 or 16 metres per second without changing the gear wheels. With the same gear ratios the speed of the winding wagon itself can be 21 or 15 kilometres per hour respectively. These speeds are generally adopted, but, if necessary, by changing the pulleys the speeds can be altered within certain limits. The possibilty of changing the speed of the haulage drum during work is of special advantage when the wagon is used for hauling turnip cutters or ploughing A number of clearly printed namemuch neglected land. plates show the driver the purpose of the different levers, so that an intelligent farm hand, after a short period of instruction, should be able to drive the wagon, thus doing away with the necessity for skilled attendants. (b) The anchorage wagon or winch used in the single winder system is illustrated in Fig. 10. It consists of a framework which carries the drums and pulleys with their gearing, the whole being supported on four wheels having High-tension Overhead Line with Switch and Connections to Transformer Wagon (on the right) with Low-tension Cable connecting to Motor Wagon (on the left). deep stability flanges. Its total weight is about 4000 kilo rms. (39 tons). In addition to the removable stability flanges on the running wheels, it is also provided with extra 0 called anchorage flanges, the distinguishing feature of which is that the stability of the wagon increases as the pull on the plough haulage cable increases. The additional anchorage flanges are carried from the wagon framework on the movable frame between the wheels, which is so connected with the cable haulage pulley that the anchorage flanges are forced either perpendicularly or obliquely deeper into the ground as the pull on the haulage cable increases, thereby obtaining a firmer hold on the soil. These flanges have the great advantage that by their use the movement or tilting of the anchorage wagon towards the plough is reduced to a minimum. This is the case because the flanges are |