CHEMISTRY AS AN AID TO CULTURAL ENJOYMENT* I
MARIONKATHLEEN FITCH, THECOLLEGE OR WOOSTER. WOOSTER.OHIO
Chemistry and chemists were once regarded as direct agents of the devil. This, however, is a chemical age. Today we live and have our being as a result of chemical processes. William Haynes, writing in the Science Monthly for May 13, 1927, has said: "Today, chemistry is not only a systematized and coordinated body of facts; it is also the tool and toy of the man of the street. In the market places or by his own fireside a man is deaf, dumb, and blind without a t least a working knowledge of the science. It is, as Br'er Rabbit once said, 'de mos' kulturines' t'ing in de world.' " Chemistry is the science of the transformation of matler, and is enormously productive, both of new knowledge and its applications. It is difficult, perhaps, to realize how profoundly chemistry influences our conception of culture and how invaluable an aid this science is to our arts. We travel to Europe, roam through art galleries and look a t statuary, we applaud famous musicians, read the thoughts of men who lived and died two hundred years ago, we lose ourselves in the dim aisles of great cathedrals, and feel more cultured in the end. But i t is not often that we give a thought to the science that has made these things possible. Chemistry seems too prosaic, too commercial and industrial to he involved in the creation of beauty. Let us consider here, however, the part that chemistry plays in the arts that go to make up culture. In the first place, chemistry has done much for literature. A few centuries ago, before the invention of printing when there were no books or newspapers and little correspondence, civilization was a t a far lower ebb than i t is now. Chemistry's important part in this enormous development has been chiefly in the production of paper and inks. Less than one hundred years ago, paper was entirely manufactured from cotton and linen rags. Now however the supply of these is insufficient to meet the demand, and less pure forms of cellulose from straw, grasses, and wood are used. The chemist is called upon to separate the cellulose from its natural state by boiling it with calcium bisulfite. The fibers thus obtained are chemically bleached, washed, and colored if desired, and are then felted together by machines. Chemistry's next aid in the process is called "sizing." A solution of alum and rosin soap, or sometimes powdered gypsum, white clay, or similar substances are added to give body and fill up the pores. Black or blue-black inks are the commonest in use for writing purposes, and are composed of an extract from gall nuts with ferrous sulfate and an acid to keep the iron in solution. A dye is usually added to make the writing show more distinctly. Some common inks are simply solutions of 'First prize-winning college essay, 1929-30. Thi* is one of the five specific titles prescribed under the general topic, "The Relation of Chemistry to the Enrichment of Life." ' 1557
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coal-tar dyes in water. Red ink is an aqueous solution of eosine. Logwood extract and potassium chromate form a hlack ink which is easily transformed into violet when it is boiled with alum and copper and filtered. Black printing inks vary in composition with the type of printing to he done. They are all pigments ground in oil or varnish. The pigment used in plate ink is generally acid-washed bone hlack, made by the destructive distillation of hones, or vine black, made by a similar distillation of almost any vegetable matter. Manganese borate is added as a drier. Lithographic and typographic inks contain organic lake pigments made from organic dyes precipitated on aluminum hydroxide, or carbon black made by the partial combustion of some fuel gas. These pigments are ground into a vehicle of linseed oil varnish, rosin oil, or petroleum oil containing dissolved paraffin. It is not so easy to put one's finger on chemistry's contribution to music, though it would be safe to say that there is no instrument made in whose manufacture the chemist has not had a part. Often this part is in the form of a varnish, in the preparation of cords for a stringed instrument, or merely in the production of the glue that cements its parts together. The phonograph, however, owes more to chemistry, for records are made by a process chiefly chemical. The record blank is a tablet of soapy wax cut in fine spiral grooves. This is dusted with graphite to make i t electrically conductive and is then slowly rotated in a copperplating bath. A homogenous deposit of copper having thus been grown, a whole series of negatives is produced from the original record. Two classes of materials are used in the common breakable type of record: rosins and gums (of which the principal example is shellac) and various mineral fillers. This composition is pressed into records in steam-heated hydraulic presses. Flexible records composed principally of celluloid are also made. They are exceptionally free from surface noises, hut are not so wear-resisting as wax. The cultural value of the phonograph cannot be over-estimated. Such organizations as the National Gramophonic Society of England with similar societies in the United States and Japan are eloquent of the part it is able to play in the musical development of the individual and of the community, and the phonograph is now being used as an educational agent for foreign language instruction in many schools. Art is perhaps more reliant on chemistry than are literature and music, for the manufacture of paints and engraving inks is carried on entirely by chemists. Chemicals have further proved an invaluable aid to art in the restoration of art treasures and their preparation for museums. Paints contain pigments and glues or gums, and are softened with glycerol or water in the case of water colors, and with oil for oil paints. The pigments are added in powdered form to drying oils-usually tung, poppyseed, walnut, or linseed. Opaque whites are chiefly derived from com-
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pounds of lead or zinc; red pigments are oxide of iron and red oxide of lead; ultramarine blue occurs naturally as lapis lazuli but a variety of shades may be produced by the action of the chemicals upon it; black pigments are usually some form of carbon. Hydrated oxide of iron containing marl yields beautiful brown pigments when ground. Among the organic pigments are those obtained from natural sources, such as annatto, indigo, and cochineal, but these are rapidly being replaced by aniline colors from coal tar. The choice of a pigment depends on its chemical and physical properties. Through scientific progress an almost unlimited variety of colors is now available. Photography can also be considered art in precisely the same way that any graphic process can be so regarded when it is dealt with by an artist. Photography is the art of producing pictures by the action of light upon chemically prepared or sensitized materials. The practice of photography depends on the sensitiveness of silver salts to light. The developing bath and the production of a positive print from a negative are chemical processes. There have been great advances in the chemistry of photography, in negative developers and printing papers, though color photography is still in the experimental stages. Another art closely related to photography is that of the motion picture which is now bringing instruction and entertainment to the people on so large a scale. The motion picture can never displace the legitimate stage completely, and many rate but low the histrionic value of such productions, but it must be taken into consideration that the screen is taking the place of the stage in many lives and that its influence has been said to transcend that of the newspapers. Classics of literature have been combed for screen material, historical photoplays have exercised a distinct educational effect and finer wit is finding its way into the movies, accompanied by the development of a better sense of humor. The millions of feet of film consumed in the making of moving pictures annually make necessary the operation of large chemical laboratories a t many studios. Here the film is made, the negative film from the camera is developed, and hundreds of positive prints are produced. The work is of a highly specialized nature and is exceedingly important. Again, chemistry is a t the root of architecture. With the development of new building materials comes a demand for a new style of architecture. Portland cement, known in the time of the ancient Romans, has been rediscovered in comparatively recent times and is now one of the most important of building materials. Glazed building tiles are another modem development and have proved nearly pexfect. Bricks also, baked in pottery kilns a t a very high temperature, are popular for building purposes. Artificial abrasives have been invented by chemists for the grinding, cutting, and the polishing of stone. With new transparent lacquers, baked
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japans and enamels, paints and varnishes, wall papers, floor coverings, rubber tiling, and leather upholstery comes a change in interior decoration. Thus chemistry is beautifying our environments. As the chemist provides not only many of ihe materials used by sculptors, but also the finishes, moulds, and methods of coloring, he also has a finger in the pie of the plastic arts. The plaster of Paris used so extensively in making statuettes and casts is calcined gypsum or calcium sulfate. One of the earliest sculptural mediums used in Egypt, Greece, China, and India is terra cotta, a chemically prepared clay. There are two important methods for the making of moulds in which a statue is cast. One is the "packed sand" mould, in which a very fine composition of clay, silica, and alumina, called Prench sand, is used. The other, and the method most in use, is the cirS perdue which demands gelatin for the negative, wax for the replica, and a semi-liquid composition of silica, plaster, and other chemicals which can resist high temperatures. Glue and gelatin moulds which are greased with a mixture of stearine and kerosene before the plaster is poured in, are also used. Finishes are of the greatest importance. They must not only be appropriate to the material and to the subject portrayed, but must also be such that they do not create a surface harmful to modeling. Marble is polished with natural or artificial pumice stone and washed with oxalic acid reduced to the consistency of table salt. Bernini was one of the first sculptors to finish his marble in this way, and Canova followed his example. A chemical composition of waxes and white spirit varnish is much used in ivory carving, and the careful polishes given to wood are chemically prepared. The exquisite "patina" permitting of the finest detail and range of color in bronzes is due entirely to the chemical composition of the bronze. Bronze must be cleaned with nitric acid before it is finished. There are various ways of tinting plaster casts so that they resemble bronze or terra cotta. One of the most common is the oil paint method. A coat of shellac is given as a prime, followed by the application of oil paint with a little dryer. The possibilities of a glazed sculpture are just being investigated. Thc ancient Egyptians used pigment on their sculpture direct with a very decorative effect. But the modern sculptor interested in color is working with his chemist to make a glaze of quality which is thin enough to hide no detail of the modeling. Ceramics is an art closely akin to sculpture. The basis is clay of varying coarseness dependent on the pottery to be produced. The materials are ground fine, made into a slip with water, and partially dried to a plastic state, in which state they are formed by pressing, throwing, and moulding into endless varieties of forms which we see daily. A glaze is
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given to the surface by covering it with a fusible flux or glass containing lead for some wares, and with a glaze composed chiefly of feldspar for porcelain. Wilson analyzed Berlin porcelain and found i t to contain principally silica and alumina with small amounts of oxide of iron, lime, magnesia, and potassia. A flux used a t S&res in much porcelain painting consists of silex, borax, and minium. The coloring matter is exclusively chemical and the modifications of tint are due to variation of the proportions or the regulation of the heat intensity. The chemistry of all porcelain work is largely the same, but even slight differences in the composition of the glazes may alter the character of the ware. The manufacture of glass and the production of the beautiful Bohemian and Venetian glassware are closely related to that of porcelain. Glass occurs in nature as a volcanic effusion known as obsidian, but man prefers to let the chemist make it for him rather than use nature's. The colors in glass are due to metallic oxides. We have followed chemistry through its relation to the major arts: literature, music, art, drama, architecture, sculpture, and ceramics, and have seen what an integral part it has in the cultural development of the world. Not only does i t have these direct bearings upon civilization, hut others more or less indirect. Travel, for example, is one of the most cultivating processes of our time, and one has but to ask himself the question, "What would travel be without chemistry?" to realize itsvital share in ships and trains and automobiles-in all, in fact, that makes for transportation. But one of the chief aids of chemistry to cultural life and enjoyment is that it has helped to put culture in the way of the masses. Books have brought literature, drama, art, sculpture, and travel to the people, and the gramophone and radio have brought music and oratory within the range of all. It is in this sense that Dr. Norman Campbell has written that science is the "noblest of the arts." Bibliography 1. "Creative Chemistry," E. E. Slosson, Century Company. New York City, 1919. 2. "Chemistry of Familiar Things," S. S. Sadtler, J. B. Lippinwtt Company. Philadelphia. 1927. 3. "Chemical Discovery and Invention in the Twentieth Century," W. A. Tilden. E. P. Dutton and Company, New York City, 1926. 4. "Chemistry in Industry," H. E. Howe. Chemical Foundation, Incorporated, New York City, 1926. 5. "Chemistry in the World's Work," H. E. Howe, D. Van Nostrand Company, New York City, 1926. 6. "Chemistry of Today." P. G. Bull, Seeley, Service & Co., Ltd., London, 1927.
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7. "Chemistry in the Service of Man," A. Findlay, Longmans, Green & Company, London and New York. 8. "Chemistry and Its Relation t o Daily Life," Kahlenberg and Hart, Macmillan Company, New Ymk. 9. "Applied Chemistry," Garard, The Mamillan Co., New York City, 1924. 10. "The Romance of Chemistry," William Foster, The Century Company, New York City. 11. "Encyclopaedia Brittanica." 12. "New International Encyclopaedia."
