WORLD CONSUMPTION OF OTHER PETROLEUM PRODUCTS World consumption of lubricating oils by geographic zones shows Europe to be the largest consumer. European countries combined account for 42-12% of the total, with the United States consuming 37.76%. Europe and the United States together use four-fifths of the world's kerosene, while the United States alone accounts for 55.7o% of the world's consumption of fuel oil. The world's merchant marine is 53% oil-burning, the total petroleum powered tonnage having increased from 6,000,000 gross tons in 1919 to over 35,000,000 gross tons in 1938.
Growth of Knowledge of Petroleum's Origin, Occurrence, and Composition.—Petroleum, known to antiquity—in fact, pre dating the dawn of man and appearing in myth and legend—al ways has been invested with mystery as to its origin, occurrence, and composition, and hence with the dawning and progression of the Age of Science has increasingly lent itself to scientific discov eries and improvements. The classification of petroleum among the minerals is probably as old as the fundamental natural history dividing things into three kingdoms : animal, vegetable, and min eral. Even this classification was not accepted without contro versy, for probably there was never a more simple, yet more com plex, substance than petroleum to provoke and challenge the chemist, the physicist, and the geologist. It has only been with the building of knowledge upon knowledge furnished by the extension of the commercial development of oil that scientific thought has been able to formulate generally acceptable answers.
While composed principally of hydrocarbons—that is, of hydro gen and carbon—petroleum is rendered complex by the uniting of these two elements in varying proportions with each other and with a number of other elements, thus forming a multitude of compounds each having distinct properties. Petroleum seems first to have been considered a liquid coal or bitumen, the connection between natural gas and petroleum not having been recognized.
During the early 19th century, as more was learned of the oils obtained from the distillation of peat, lignite, and coal, the belief grew that petroleum was produced from one or all of these materials by the action of subterranean heat upon solid bitumens. At the same time the theory that petroleum was formed in the earth by chemical reactions in connection with volcanic disturb ances, accompanied by great heat, made headway. This is termed the inorganic theory of origin.
As oil development progressed on a commercial scale in the United States and other countries, the organic theory of origin began to be advanced. This held that petroleum was produced by the decomposition or distillation of animal or vegetable matter. It was not until the 2oth century that anything like a clear pic ture of the origin of petroleum was developed and this was made possible because of increasing study of wells drilled for oil and of formations penetrated by the drill. These studies seem to bear out the organic theory. It is generally held that plant and animal organisms were the origin of oil, that these organisms, buried in ancient seas of the geologic yesterday by new mud deposits and sealed from the air, were subjected to slow decomposition and formed the petroleum of commerce. Much is yet to be learned in this field. Important research on the origin and environ ment of source sediments of petroleum was instituted beginning in 1926 by the American Petroleum Institute under a fund pro vided by the late John D. Rockefeller and the Universal Oil Products Company of Chicago. Projects underway cover a wide range of inquiry into the still unsolved problems of the origin, occurrence, and composition of petroleum.