Even if we consider the agency of the streams that now are but insignificant inflowing brooks in spreading, during their freshet stages, sand over level areas, we must still go back to a time when they were streams of infinitely greater magnitude than they have been for many centuries, and before, too, the Indian was a skilled chipper of jasper and a potter of taste, else why the absence of these products of his skill in the deeper sands? It matters not how we look at it, whether as geologists or archæologists, or whether it is all post-glacial, or the starting point is still so distant as ice-age activities, the sequence of events is unaffected. We still have paleolithicity in the gravel, argillite and the discovery of pottery synchronous with the deposition of the gravel-capping sand, and, lastly, the Indian.
The record is not a difficult one to read, and never has been, and the manifold attempts to modernize all traces of man on the eastern coast of North America can safely be relegated to the limbo of misdirected energy. Studied in the proper spirit and after the needful preliminary study of archæology as a whole, the student will find himself, when in the field—ever a more desirable place than the museum—face to face with evidences of an antiquity that is to be measured by centuries rather than by years.
THE USE OF ACETYLENE.
By EDWARD RENOUF,
COLLEGIATE PROFESSOR OF CHEMISTRY, JOHNS HOPKINS UNIVERSITY.
It is now five years since the use of acetylene as an illuminant was suggested to the public, and it may be of interest to give a sketch of what has been done during this time, especially as it seems that with the year 1899 the tentative period which must characterize every new industry is in some respects passed, and a period of solid and well-directed industrial effort, backed by ample capital, has begun. The knowledge gained during this tentative period by the laboratory experiments of scientific men, and by the practical work of inventors and promoters, has made it possible for the industry to enter on its new phase. To understand its present and to foresee its future importance it is necessary briefly to review the work of the last years.
In May, 1892, Mr. Thomas Willson, a Canadian electrician, tried to make the metal calcium in an electric furnace in his works at Spray, North Carolina, by heating a mixture of lime and coal dust. He thought that the lime (calcium oxide) would act on the coal (carbon) to form calcium and carbon monoxide. He did not succeed in getting calcium, but found in the furnace a brown, crystalline mass, which was decomposed by pouring water on it, yielding an inflammable gas. Willson is not a chemist, and he therefore sent specimens of the material to several men of science to determine its nature. It was shown to be calcium carbide, a compound of calcium and carbon, formed by the action of the carbon on the calcium oxide. The reaction expressed in chemical symbols is CaO + 3C = CaC2 + CO. The gas formed by the action of water was acetylene, a compound of carbon and hydrogen. The reaction is CaC2 + H2O = C2H2 + CaO; calcium carbide and water form acetylene and lime. If water enough is added, the lime is slaked, and slaked lime, or calcium hydroxide, Ca(OH2), is formed. Neither calcium carbide nor acetylene was a new discovery; acetylene was discovered by Edmund Davy in 1836, and its properties were studied by Berthelot in 1862. Impure calcium carbide was first made in 1862 by Wöhler, who described its decomposition by water into acetylene and lime. What was there new, then, in Willson's discovery? Two important facts: (1) He was the first to make carbide by a method applicable commercially; (2) he was the first to make crystalline carbide. Wöhler's carbide was impure and amorphous; Willson's, nearly pure and crystalline, so that he succeeded in obtaining United States patents for crystalline carbide, and, as all carbide made by commercial processes is crystalline, its manufacture is covered by Willson's patents.
In the same year, 1892, Prof. Henri Moissan, of Paris, announced the discovery of crystalline calcium carbide. Moissan's discovery, too, was an accidental one. He was reducing refractory metallic oxides in an electric furnace made of lime. At the close of the article in which he reports his work to the French Academy of Sciences (Comptes Rendus de l'Académie Française, vol. cxii, page 6, December 12, 1892) he refers in two lines to the formation of an ill-defined carbide of calcium by the action of the carbon electrodes on the lime of which his furnace was made.