T H E J O C R N A L OF I N D U S T R I A L A N D EJTGIXEERISG C H E M f S T R Y a Portland cement as was made in Europe. These men turned the matter over to chemists, who were given entire charge of the manufacturing process. It was very soon demonstrated that American Portland cement manufactured in this manner was absolutely as good as the foreign cements which hitherto had enjoyed a much better reputation. There was still considerable prejudice in the minds of the users of the cement and in the minds of engineers and architects; they argued that, while the short-time tests were satisfactory, there was nothing to indicate that the cement would give normal tests for longer periods of time. Further work by chemists proved, to the satisfaction of all reasonable men, that the constituents of American Portland cement and Imported Portland cement were not very different 'and that there was every reason t o believe that the long-time tests would be just as satisfactory as the shorttime tests were. This conclusion was amply demonstrated. Having proven that it was possible to manufacture cement really of a better quality than that hitherto imported, the next step before the manufacturers was to reduce the cost, so t h a t Portland cement could be sold to consumers a t a price which would warrant them in extending its use and substituting i t for other forms of construction. I n the original factories the clinker was burned with oil. The kilns were short and the process was very wasteful of fuel. Along towards the end of the 19th century the price of fuel oil began to go up and reached such a point that the life of the cement industry in the United States was seriously threatened. Again recourse was had to the chemist, and after many experiments the system of powdering coal and burning i t in kilns was perfected. This pow^ dered coal took the place of fuel oil and resulted in a very marked reduction in the cost of manufacturing cement. Further than this, experiments were also conducted along lines indicated by theory and longer kilns were built, this again effecting a reduction in the cost of cement. Many other reductions in the cost of the manufacture of cement were made by reason of the investigations of the chemist, probably the most important being that of handling the raw material in large quantities direct from the quarry. This method took the place of the old scheme, whereby the stone of different compositions was gathered in separate bins and then distributed in proper quantities throughout the mill. The present practice is to mix the raw stone in the quarry, thus greatly reducing the cost of handling. So much for the manufacturing itself. I n the realm of the use of Portland cement the chemist has also done much. He has been particularly active in educating those who use cement t o the necessity of seeing that the aggregates used with the cement are of proper quality. He has also given a great deal of time to the development of specifications which will protect the user of cement. Originally, each engineer had his own specifications and many of them were most peculiarly and wonderfully drawn. The energetic efforts of the chemist practically eliminated all of these freaks and we have today, through his efforts, standard specifications which insure to any user of cement an absolutely sound article. Time would fail me to go into the detail of all the problems which have come up in our business and which have been successfully solved through the efforts of the chemist. Careless manipulation in mixing concrete often resulted in walls that were not water-proof. While it is easily possible, with careful attention to the aggregates and mixing, to get an absolutely water-proof concrete wall without the use of any so-called water-proofing, the fact remains that in the hands of the ordinary user of cement proper care may not be taken. The chemist, therefore, developed a water-proofing material w-hich, when added to the concrete, prevents water from seeping through. Problems in connection with the storing of clinker, sorting of cement, the operation of our power plants, quarry conditions, etc., all have been referred to the chemist and by him put in process of solution.
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The fact that the chemist is responsible for the quality of the cement to such an extent that he controls the operation of the mill, is largely advertised by a t least one of the larger cement manufacturing companies in the United States. EASTON, PA. CONTRIBUTIONS OF THE CHEMIST TO THE SUGAR INDUSTRY By W. B. HORXE Consulting Chemist
Chemistry as a science has contributed so much toward the development of the sugar industry from the beginning that the association has been a continuous one and cannot be looked upon as having been abruptly formed a t any particular time, but rather as having been the principal factor in the development of sugar manufacture. Thus the influence this science has exerted upon the industry during the past quarter century should be viewed in relation to what has preceded and what will follow. Much of what chemistry is doing now is the development of earlier work and will continue to exert its influence upon the future. Every department of the industry has long been under searching chemical investigation in almost every detail. Agriculture, manufacture, refining and utilization in the arts have called for chemical assistance and have received noteworthy aid. Very many new processes have been developed, better methods of analysis have been devised and theoretical knowledge OF the constitution of the sugars has been substantially advanced. A vast literature is maintained on the subject of sugar, the main division of which is chemical. The International Commission for Uniform Methods of Sugar Analysis, composed of leading sugar chemists from the principal sugar-producing countries of the world, has done a great deal of good work in revising analytical methods, prescribing standards for apparatus, calculating working tables and generally supervising the field of sugar analysis. Emil Fischer introduced the use of phenylhydrazine as a reagent in studying the theoretical molecular constitution of the sugars. This reagent's property of reacting with the aldehyde or ketone group of a sugar molecule and the adjacent alcohol group has rendered the highest, service in studying the constitution of the sugars, as pursued for many years by Fischer, Rerzfeld, Mulliken, and many others. The development of sugar in the cane has been carefully studied by Prinsen Geerligs in Java and the occurrence. of the nitrogenous constituents in the beet by Saillard in France, not to mention a n almost endless series of similar investigations by other chemists in every branch of plant physiology and development. The influence of soil composition and the effect of fertilizer ingredients has also received detailed study, including the remarkable effect on plant development caused by the action of minute quantities of manganese in the soil upon the enzymes in the grow-ing plants. A great deal of work has been done on the development of nem varieties of cane through raising seedling plants and selecting, largely through chemical analysis, the best individuals for further propagation. Thus the famous D 74 has been developed in Demerara and equally good varieties in Java and other countries. In Java, a few years ago, the sugar industry was threatened with destruction through the prevalence of insect pests and other troubles which beset the cane with accumulating force. The development of new varieties through chemical and biological work alone reclaimed the industry and placed it upon a very profitable basis. I n the manufacture of raw sugar, the past quarter century has seen great advance through bringing factories under chemical control, and the cane industry has caught up with and surpassed the beet industry through its scientific development on these lines. The consumption of sugar in the United State.s
Apr., 1915
T H E J O U R N A L O F 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 ST R Y
has risen from 1,500,000tons in 1890 to 3,750,000 tons in 1914 and the per capita consumption from 54 pounds to 84 pounds per annum. This has been partly due to the cheapening of sugar through scientific management in its production, raw sugar having fallen from 2 . 8 8 cents per pound (without duty) in 1890 to 3 . 0 3 per pound in 1914, and this, too, in spite of a rise in price of all other food staples, averaging considerably over 15 per cent. In making raw sugar the proper defecation and clarification of the juice are chemical m:tters of first importance and during twenty-five years great improvements have been made in the double carbonation process both for beet and cane, the use of sulfitation of the thin carbonated juice, and the use of phosphoric acid and its salts as additional defecating materials. Rieselguhr has been introduced by Wiechmann as a clarifying agent and is now being used more and more extensively, especially since the development of the great Lompok deposit in California. Raw sugar factories are now producing white sugar directly from cane as well as from beet, due to chemical investigations of the matter and chemical control. Raw sugar factories are now generally able to sell their molasses instead of throwing it away, because of chemically developed methods of converting it economically into alcohol, cattle foods when mixed properly with bagasse, peat moss, etc., and into other useful products. The sugar is all recovered from beet molasses by the Steff ens process of conversion into tricalcium saccharate, and the by-products from this are going into fertilizers, cyanides, etc. Wax is recovered from scums and the residues utilized as fertilizers in the cane fields. Paper is made from the unused fiber of the cane and another by-product has been improved by the chemicalinvestigationsof themanufactureof rum. I n sugar refining, due to chemical research, invention and control, progress has been made all along the line. Better methods of enclosing samples of raw sugar have led to better agreement in tests through preventing changes in moisture. The establishment of the Sugar Trade Laboratory in New York, under Dr. C. A. Browne, has placed the polarization of sugar samples for seller and buyer upon a satisfactory scientific basis, free from bias. Well-equipped laboratories are maintained by all factories and refineries where routine testing and analytical work are carried on constantly and where investigations are made. The Bates polariscope with adjustable sensitiveness is a recently developed aid of great value to all this work. Anhydrous subacetate of lead, introduced by Horne, has simplified the polarization of impure solutions and greatly reduced the time and labor of making tests. New analytical methods are constantly being developed along with more convenient apparatus. The refineries have given up the use of blood as a defecating agent in favor of acid phosphates, and the tendency is towards the use of flocculating agents which will produce no objectionable side products. Certain solutions containing invert sugar are cleared of this constituent in the Batelle process of heating with sufficient lime to destroy the invert sugar without harming sucrose. The Weinrich dry-lime process undertakes, by treating concentrated impure sugar solutions with pulverized lime a t low temperatures, to effect a nice differentiation between organic non-sugars and invert sugar, whereby the former are largely removed along with some salts and q o s t of the color, without affecting the valuable invert sugar. Progress has been made in electric defecation, but objectionable features of expense still await surmounting. Liquid sulfurous acid has to some extent beneficially replaced the gas, while the hydrosulfites of soda and of lime are used by many in massecuites and in syrups for improving color and yield. The practice of boiling back the syrups from previops massecuites has greatly developed, due to the increasing facility in testing all products in the laboratory and the increased precision of work possible
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because of this more intimate knowledge 6.f the purity of every part of material in operation. Crystallization in motion has been developed to a fine point with great increase in yields. A more thorough exhaustion of the sugar from molasses has been arrived at, partly through the light thrown on this subject by chemical investigations such as that made by Prinsen Geerligs on the subject. Potash salts are more thoroughly removable through the permutit process which employs alkaline silicates similar to the natural zeolites for the purpose. Water supplies can be purified by the same process. New dyes have been developed to take the place of ultramarine, sometimes used to give a certain tone of white to some refined products. The treatment of bone-black has been improved by the gentle oxidation obtained in the Weinrich decarbonizer. The increasing price of bone-black has led to the invention of various carbonaceous substitutes, among which can be mentioned Norit or Bponite favorably reported upon by the late Dr. Strohmer, and which its manufacturers claim to be capable of yielding white sugar direct from cane juices. Patterson has contributed materially to our knowledge of the composition of bone-black, but much remains to be learned concerning this material. The last 2 5 years have witnessed the giving up of the attempt to commercialize sorghum sugar and the enormous development of the beet sugar industry within the United States, in both of which credit falls to Dr. Wiley, aided by many other well-known chemists. What chemistry will do for the sugar industry in the future is a question of deep interest, and the answer will probably be found in simplified processes of defecation, cheapened materials for color removal, etc., more energetic chemical treatment of low-grade intermediate products and a better utilization of such by-products as are inevitable. The service of chemistry in the past leaves no misgivings for the years that are to come. 175 PARK AVENUE,YONKERS, N. Y.
CONTRIBUTION'S OF THE CHEMIST TO THE INCANDESCENT GAS MANTLE INDUSTRY By SIDNEY MASON President of the Welsbach Company
No article more strikingly emphasizes the importance of the science of chemistry than does the incandescent gas mantle, which owes both its inception and development, up to the towering output in the United States alone of upwards of 80,000,000 mantles annually, to the untiring effort of chemical research. This industry, founded on the remarkable discovery and invention of Baron Carl Auer von Welsbach almost thirty years ago, has progressed along a trail blazed by the Chemical Engineer, Baron Auer, a chemist and scientist of world-wide reputation, who having as a lad been engaged in a scientific study of the rare earths, observed the phenomena that suggested t o him a new system of gas illumination. Previous researches of the rare earths by earlier chemists stimulated his desire to work in this field, which he undertook at the beginning for the purpose of contributing to the knomledge of this branch of chemistry, but which culminated in his demonstrating that a vegetable or organic fiber could be perfectly reproduced in mineral form by certain rare earth oxides sufficiently coherent and attenuated to become brilliantly incandescent in a non-luminous gas flame. By patient and persistent chemical research for a period of years, the Welsbach gas mantle eventually reached a state of perfection which crowned the work of the inventor with commercial success The spectacular discovery that a mantle made of thoria with a small admixture of ceria would increase the lightgiving efficiency of previous mantle compositions more than three-fold, provided the impetus necessary for this purpose
