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organizations would be included. According to McClellan, the present lack of unity has prevented the engineering profession from exerting its proper influence in the solution of economic problems and has also prevented the profession from having the standing it deserves among the learned professions. Among the functions of such a general engineering society as that proposed would he arrangement of an annual convention for the discussion of engineering in general, the holding of semiannual meetings, investigation of various subjects, appearance in national and civic matters, etc. To carry such a scheme into effect, it should have the support of a t least three of the national engineering societies. In the discussion of McClellan’s paper, hlailloux characterized it as one of the most interesting contributions presented before the Institute in a long time. This, he said, is one of the means of raising the status of the engineering profession; the proposal should, therefore, be fostered and promoted. Oberlin Smith indorsed the proposal, hut felt that too much clannishness among members of different national engineering organizations exists to make the project feasible just yet. The civil engineers, he continued, still consider that their society represents all the domain of engineering except military engineering, although there is a growing sentiment among many of them for a united national society. C. L. Clarke, who indorsed the plan of McClellan, urged that clannishness would be no obstacle to its accomplishment, because none of the functions of any of the constituent societies would be disturbed. D. C. Jackson and C. L. de Muralt also indorsed the plan. I n a paper by Burton McCollum and K. H. Logan was discussed generally the subject of electrolytic corrosion of buried iron from outside current sources as well as from self-corrosion within the piece itself. The two actions are to a large extent interdependent, the existence of one affecting largely the occurrence or severity of the other. In the tables of experimental data compiled by the authors the factors are given which are most likely to effect electrolytic corrosion of buried pipes under practical conditions. Among these elements are current density of discharge, moisture content of the soil, presence of oxygen, temperature, voltage, etc. I n the laboratory tests carefully cleaned iron anodes were tested in cans of sifted earth moistened with distilled water. Meanwhile, check specimens of iron were also embedded in protected sections to investigate simple self-corrosion. Detailed precautions were necessary in the preparation and cleaning of the specimens. To afford a variety of practical conditions, soils from various localities were used in the tests. The authors discussed briefly earth resistance. polarization and surface-film resistance, presenting tables
of results of specific resistance and corrosion tests, etc. A number of practical conclusions were drawn from the experiments, it being found, among other facts, that corrosion is most efficient a t low current densities and is independent of temperature, of depth of burial and of the oxygen present in electrolytes. Soil resistance varies with moisture content up to the point of saturation. Information of interest to the industrial power engineer was given in a paper by C. 4.Kelsey outlining the principal operations in the process of working up raw rubber. This material has a large capacity for absorbing power and is greatly improved by such working. Motor drive of sheet rolls involves an irregular load with abrupt peaks. Mixing, masticating, tubing, calendering, etc., are some of the other operations involving special applications of motors. Certain operations of “working ” and mixing also have heavy overloads of short duration, but these diverse demands, by grouping under a single motor, result in reduced peaks. For individual drive, squirrel-cage induction motors are preferable. In the calendering processes where close speed control over ranges of four to one is required, direct-current motors may be used to advantage, speed adjustments being effected by the multi-voltage and adjustable-voltage methods. The tubers also require direct-current operation. As the power required to drive the mills is by far the greatest part of the total requirements, alternating-current service is generally selected. The motor-generator set or synchronous converter used to supply direct current can then be used for power-factor correction of the main circuit. I n conclusion, there was given a comparison of methods for obtaining adjustable-speed operation, with emphasis on the features to be embodied in the control. INTERNATIONAL ASSOCIATION OF CHEMICAL SOCIETIES Monsieur Ernest Solvay, of Brussels, has intimated his intention to place a t the disposal of the International Association of Chemical Societies a sum of nearly a million francs for the purposes of the Association, together with rooms in his Institute in Brussels. Prominent members of the Association suggested that i t would be fitting that its meeting in September should take place in Brussels instead of in London, in order that the members present may have an opportunity of conveying their thanks personally to Monsieur Solvay for his munificent gift. The next meeting of the International Association of Chemical Societies will, therefore. be held in Brussels, beginning September 19, 1913.
NOTES AND CORRESPONDENCE, GERMAN MANUFACTURE OF BARIUM COMPOUNDS
Consul Thomas H. Norton reports that until recently heavy spar-barium sulfate-served almost exclusively in Germany as raw material for the manufacture of barium oxide, barium hydrate, barium peroxide, and the various salts of barium. The sulfate was reduced by heating with coal in kilns to the form of the sulfide. From the solutions of the latter, barium carbonate was precipitated by the action of carbon dioxide. This carbonate served as the starting point for the preparation of the chloride, the nitrate, the oxide, etc. It has now been found possible by the process of b’. Feld (German Patent No. 149,803, of 1 9 0 1 ) to reduce directly natural barium carbonate (witherite) to the form of oxide by heating in retorts in the presence of a fuel free from hydrogen. The cheap witherite of England is now imported in considerable quantities into Germany to serve this purpose. The import
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amounts annually to about + j O metric tons, valued at S16.6j per ton Several other methods ha\-e been patented in Germany, but it is not known to what extent they have been introduced as technical operations. A. Frank patented in 1901 (German Patent No. 135,330) a process based upon the interaction betwekn barium carbide and barium carbonate when mixed and heated. 3BaC0, 1. BaC, = qBa0 -C j C 0 There is a vigorous evolution of gas, and when this ceases the reaction is complete. H. Schulze, of Bernburg (German Patent KO. 240,267, of 1 9 0 j ) , finds it possible to secure a very porous form of barium oxide by the direct reduction of the carbonate, if the retort employed for the purpose is lined with carbon, and if a narrow space is left free between the walls of the retort and the mixture of carbonate and coal. Otherwise. compact crusts are formed
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adjacent to the walls and particles of coal are inclosed in them. In a patent of later date (German Patent No. 231,645, of 1909) this inventor describes an additional method of effecting the reduction of the carbonate with coal. Use is made of an electric furnace, and the mixture of mineral and coal is exposed to combined electrothermal and electrolytic action, forming itself a part of the circuit. The reaction mass is an excellent conductor of the electric current a t a high temperature. The barium oxide thus obtained is of a high degree of technical purity and possesses a uniformly porous structure. The electrolytic process has been developed in the wet way by the Siemens & Halske Co., of Berlin (German Patent No. 241,043, of 1910). They make use of the facts that chloric acid and perchloric acid are only slightly affected by either the nascent oxygen liberated on an anode or the nascent hydrogen freed on a cathode, especially in the latter case, if the cathode is of silver or platinum. Use is made of a diaphragm apparatus. Solutions of barium chlorate or perchlorate serve as electrolytes. Barium carbonate is suspended in the anode cell, so that the acid liberated is immediately neutralized while the equivalent amount of barium oxide is formed in the cathode cell. M. Herzberg proposes in his patent of 1907 (German Patent No. 195,278) to facilitate the decomposition of barium carbonate at a white heat by introducing substances that react with carbonic oxide and thus remove it. He accomplishes this, for example, by mixing barium peroxide with the carbonate. Siemens & Co. (Germanpatents No. 158,950, of 1903, and No. 200,987, of 1907) claim to secure very good results by heating a mixture of barium carbonate, barium nitrate, and coal in an electric furnace to a white heat. The reaction is: BaCO, A Ba(NO,), zC = zBaO zNO, 3CO The decomposition of the carbonate begins as soon as nitrous vapors are evolved. Explosions are avoided by mixing the components with tar, and forming the mass into sticks. The process is continuous, and the resultant product is quite porous. A somewhat similar method has been introduced by H. Schulze to change compact masses of barium oxide into the porous form. The oxide is mixed with barium nitrate and powdered coal, and this mixture is heated in an ordinary retort kiln or in an electric furnace. Favorable proportions are 88.5 parts of barium oxide, I O parts of barium nitrate, and 1.5 parts of coal dust. The reaction is violent, and the product quite porous, in consequence of the large volume of gas liberated.
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REDUCTION O F BARIUM SULFATE WITH COAL I N ELECTRIC FURNACE
Bradley and Jacobs (German Patent No. 111,667, of 1898) claim to secure fair results by the reduction of barium sulfate, with coal in an electric furnace. The basis of the reaction is the interaction between resultant barium sulfide and unchanged sulfate: 3BaS0, B a s = 4BaO 4SO, In practice the operation yields a mixture of 60 per cent BaO and 40 per cent Bas. After extraction with hot water, barium hydrate crystallizes from the solution. The same 'chemists claim to secure BaO in an exceedingly porous form by fusing together, a t an elevated temperature, a mixture of barium carbide and barium hydrate in molecular proportions. The residue, after the expulsion of all hydrocarbons, consists of highly porous barium oxide (German Patent No. 142,051, of 1898).
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ELECTROLYSIS OF AQUEOUS SOLUTIONS OF BARIUM SULFIDE
Brochet and Ranson (German Patent No. 129,324, of 1901) secure the hydrate by submitting aqueous solutions of barium sulfide to electrolysis. The concentration is 90 grams of sulfide in the liter for the solution in contact with the iron anode. A diaphragm is used, and the temperature is maintained at 50° C. The current employed has a tension of 1% volts and a force of 5 amperes per square decimeter. A dilute solution, containing 5 0 grams per liter, is introduced in the cathode compartment.
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Barium hydrate is formed in this compartment and remains in solution while the temperature is maintained a t 5 0 ° . From time to time the solution is drawn off, and the hydrate crystallizes out on cooling. Conductivity is increased by adding chlorides t o the solutions. The addition of a layer of paraffin oil prevents any formation of carbonate. If chlorides are present, porous chloride is formed about the anode. This reacts with the sulfides in solution, and a precipitate of sulfur and of ferrous sulfide is gradually deposited. H. Nordlinger (German Patents No. 132,433 and No. 133,691, of 1901) has devised a method for decolorizing the solutions of barium sulfide obtained by the lixiviation of the crude product resulting from the reduction of heavy spar with coal. He adds I per cent to 2 per cent of a solution of caustic soda (36O Baum6). All color vanishes and there is a marked increase in the readiness to crystallize, the crystals being perfectly colorless. Similar effects are produced by the addition of ammonia water. The introduction of a slight amount of formaldehyde overcomes all danger of oxidation. W. Mostowitsch has lately investigated the reduction of barium sulfate by heating with coal. He finds that the reaction begins a t 6 m 0 C. and is completed a t 80o0 C. At lower temperatures the reaction is: BaSO, 2C Bas zC0, At higher temperatures it is : BaSO, 4C = BaS 4CO Barium sulfide remains unchanged a t a temperature of 1,000~ C. In producing barium hydrate from crude solutions of barium sulfide, G. Schreiber (German Patent No. 154,498, of 1902) recommends the following method: The liquid is saturated with hydrogen sulfide, and the resultant solution of barium sulfhydrate is concentrated in a vacuum apparatus. This is treated with cold, concentrated solutions of the alkaline nitrates or of calcium nitrate (Norway saltpeter), and barium nitrate is precipitated. The crystalline product is purified in a centrifugal. An important advance in this field has been achieved by K. PUIS,K. Krug, and coworkers (German Patent No. 198,861, of 1907), who also make use of the cheap and relatively pure calcium nitrate now supplied in increasing quantities by the Norwegian works. Witherite, BaCO,, is finely ground and introduced into an aqueous solution of the nitrate. The mixture is then heated in a digester, provided with an agitator, under a pressure of from I t o 2 atmospheres for 4 hours. After removal The from the digester, water is added and the mass boiled. precipitate of calcium carbonate is removed by means of a filter press and the residual solution of barium nitrate evaporated to the point of crystallization. Traine and Hellmers (German Patent No. 204,476, of 1907) propose a variation to this method. Instead of witherite they employ barium oxalate or barium phosphate, which has been precipitated from solutions of barium sulfide. An important process for the reduction of barium sulfate that promises t o simplify materially the manufacture of soluble barium compounds is due to C. A. Beringer, of Charlottenburg (German Patent No. 249,857, of 1912). He keeps a mixture of heavy spar ( 7 parts) and clay ( 3 parts) for some time a t a bright red heat and brings about the formation of a double silicate of barium and aluminum. This is readily susceptible to decomposition by hydrochloric or nitric acid.
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PEAT AS FUEL' Reports of the growing use of peat as fuel in Europe have stimulated the interest of owners of peat land in the United States, especially in those parts of the country where other fuels are high in price, and many attempts have been made to make 1 Abstract of paper presented at the Eighth International Congress of Applied Chemistry, New York. September, 1912.
