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THE J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y .
The cost of production of alcohol by the sawdust process (Ruttan, J . SOG.Chew. Ind., 1909,p. 1290) is said to be about equal to that of grain, although there is such an enormous difference between the cost of the raw materials. One company, however, claims t o be able t o manufacture alcohol by the sawdust process a t a cost of $0.07 per gallon. Without going into the details of the chemistry involved, it is striking that, although the patents claim a conversion of cellulose into sugar, the so-called true fibrous cellulose, absorbent cotton, does not yield t o this treatment. Also the material left after treatment contains cellulose which upon re-treatment yields but traces of fermentable sugar. Although authorities differ, it is claimed by some t h a t the acid acts as a catalyzer hydrolyzing the lignone complex and a proportion of the “easily attacked cellulose.” The oxycellulose and the “true cellulose” are said not to be seriously altered chemically. I t would seem that there is a possibility that a process might be evolved where the alcohol conversion of the wood pulp might be made first, and then the residue subsequently utilized for the production of paper pulp. ALCANHIRSCH. OCCUPATIONAL DISEASES.
This subject is now receiving the attention it deserves. Hitherto the matter of diseases peculiar t o industries has been in the hands of physicians. While medical men are competent to treat and cure such diseases i t can readily be seen that they are unable b y nature of their training t o accomplish much in the elimination of the causes of occupational diseases. The physician is not the proper person to suggest t o a manufacturer such changes in his processes as will eliminate the causes of the peculiar occupational ills
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July, 1912
to which his employees are subject. This is necessarily the function of the chemical engineer and i t is to him that the physician now turns for assistance. The June number of THISJ O U R N A L published an address delivered by Dr. W. Gilman Thompson, Professor of Medicine in the Cornel1 University Medical College, in New York City, before the New York Section of the American Chemical Society. The attention of our readers is called to the facts set forth and the points brought out in this address, and chemists will readily see the opportunity which presents itself to them, to be of assistance in this crusade of the Twentieth Century. The New York Section of the American Chemical Society has appointed a Committee on Occupational Diseases, which is now cooperating with a similar Committee of the New York Association for Labor Legislation. The personnel of these committees is given in another column of this issue. A joint meeting of the two committees was held on May g ~ s t a, t the Chemists’ Club in New York City. This meeting was addressed by Dr. Alice Hamilton, whose work of investigating lead poisoning for the U. s. Department of Labor is well known. Dr. Hamilton spoke of the difficulties she had experienced in obtaining information, and laid particular stress on the importance of the cooperation of the chemist and physician. It will be readily seen that this is a matter for organized and systematic work by our profession, and that the campaign must be one of educating the public, the workingman, and the manufacturer. I t is evident that statistics must be collected so proper lines of work can be designed. More will be accomplished by education than by inconsidered or hasty legislation, and b y this method the least possible hardship will be inflicted on established industries. E. C. UHLIG.
ORIGINAL PAPERS
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The acid theory presumes that corrosion is primarily caused by acid attack. It denies the solubility B y WILLIAM R. FLEMING. of iron in pure water and denies that iron will rust I n a recent article in the Irovt and Steel Institute,a in acid-free air and water combined. Dr. J. Newton Friend again attacks the “Electrolytic” The electrolytic theory presumes that iron is soluble Theory of Corrosion. I n his Paper, a Carnegie Schol- in pure water, and that rust is subsequently formed arship Memoir, he describes an experiment which through the influence of oxygen. The exposed surdemonstrates that “Pure water and pure air combined faces of iron and steel contain segregated impurities are without visible action upon pure iron.” “This which are supposed to give rise to differences of poshows, Friend continues, that the electrolytic theory tential, in the presence of an electrolyte, which is of corrosion is untenable, and definitely confirms the generally moisture. At those points where the metal older acid theory.” is anodic, iron passes into solution, assuming the I n this paper I shall attempt to show that iron and ferrous ionic condition, while hydrogen is liberated steel will rust in pure water and air combined, if it a t the cathode. Oxygen plays its part by depolarizing is given a chance. Furthermore, I shall attempt to the hydrogen covered cathodes and by oxidizing the prove that Friend’s experiment is a strong confirma- ferrous ions a t the anodes. In its purest sense the tlon of the electrolytic theory, and not destructive electrolytic theory presumes that corrosion begins to it. in a pure electrolyte, e. g., water free from all traces We have to-day only two important theories of of impurities. corrosion, the “Acid” and the “Electrolytic” theories. The defendants of the acid theory deny the solu1 Read before the Cincinnati Section of the A C. S., February 14, bility of iron in pure water and are emphatic in their 1912. claim that corrosion is “primarily the result of acid 2 Iron am$ Steel Insfztufe, 3, 1 (1911). CORROSION OFIRON INPUREWATER AND AIR COMBINED; THE ELECTROLYTIC THEORY AGAIN CONFIRMED.’
