VOL. 8. NO.3 CHEMICAL INDUSTRIES AND RAW MATERIALS
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they are not used directly in the chemical industries but become a chief source of power. The coal area of Maryland has an extent of approximately four hundred fifty-five square miles and the original supply, before erosion or mining, has been estimated as over eight billion tons. The annual production is about four million tons and the total exhaustion something over eight million tons, leaving the greater portion of the original supply still in the ground. Beneath the coal occurs a stratum of highly refractory fire clay which has been the basis of an extensive industry in the manufacture of enameled brick. The high-grade fire clay is used for the manufacture of the highclass brick, and on it is flowed an enamel mixture of fire clay and fusible constituents which may be melted into glass without fusion of the brick itself. The compounding of a glaze which will have shrinkage value the same as that of the underlying brick during cooling is one of the most delicate chemical processes carried on among the chemical industries in Maryland. The foregoing discussion of the chemical industries of the state shows that while the raw materials of Maryland a t the present time are but little used, their occurrence in the state during the period of infancy of the chemical industries in the United States exercised a powerful influence in determining the location of these chemical works. I t is also interesting to recall that it was the chrome industry in Maryland which led to the first regular employment of a chemical engineer in the United States.
War Gases Tested as Medical Weapons. Mustard gas, dreaded weapon of the World War, has been reported as possibly preventing and curing a number of diseases. The latest peacetime development of this gas is the announcement by the British Empire cancer campaign that it may prevent cancer in areas of the skin which have been painted with tars that ordinarily produce cancers. This does not in any way mean that mustard gas will cure cancer. Even its preventive action is extremely limited. But recent investigations may lead t o a more general preventive method, it is said. The starting point for the experiments leading to this discovery may have been the reported British observation that none of the British soldiers who were exposed to mustard gas in the war ever developed cancer, i t has been suggested. German experiments along similar lines have also been reported. Previously mustard gas had been heralded as a cure for locomotor ataxia, and other war gases were tried as cures for colds, tuberculosis, and various respiratory diseases. Mustard gas is a sulfur compound, dichlordiethyl sulfide. Recently a Philadelphia scientist, Dr. Frederick S. Hammett, suggested that control of cancer might be gained by means of another sort of sulfur compound. He did not claim t o have found any cure for the disease. However, he did state that transplantable tumorous growths in mice had been made to diminish and in a t least one case to disappear altogether by the application of an organic compound containing partially oxidized sulfur-Science Sewice