Decembke 1, 1897.] 



KNOWLEDGE. 



2S5 



the north-west of Africa, throngh the Alps and their 

 offshoots, through Cyprus, the foot of the Himalayas, 

 and down to the isles on the west of Sumatra, the 

 contorted border of this modern continent can be con- 

 tinuously traced. We have already seen how marine 

 invasions from the north occurred across Eurasia in the 

 Post-Pliocene period, in which we actually live. In North 

 America we have a solid mass of highlands, which 

 thrust oft" the brackish waters of the Laramie Beds at the 

 very opening of the Tertiary era. But there is no great 

 stability in a mass that is bounded on the west by the 

 active zone of the Pacific : * and it is well known that 

 even in the plateaux of I'tah, five hundred miles from the 

 coast, there are faults of such recent character that we 

 may assume that powerful movements, of continental 

 magnitude, are still being carried on.+ 



The conviction of students of the Himalayan border, 

 that the great ranges of Central Asia have not yet come 

 to rest, has been strengthened by recent observations ; 

 and the upward and outward movement of the ritn of 

 Suess's Eurasia may result in remarkable changes in the 

 Mediterranean and the Indian Ocean. A curious tongue 

 has already shot forth from the new continent, and has 

 formed what we know as Italy and Sicily, which date only 

 from Pliocene and Post-Pliocene times. Not only do 

 bands of marine Lower Pliocene strata lie upon both 

 flanks of the Apennines from Turin to Calabria, but iu 

 SicQy the highest beds, abounding in living species of 

 mollusca, are found already elevated three thousand feet 

 above the sea. 



In the heart of our continents, then, mountains have 

 doubtless yet to rise, while new areas of subsidence, 

 ringed about by faults, have yet to be provided to receive 

 the products of their decay. Only in exceptional cases 

 can we watch these epic movements as they proceed. 

 Usually denudation is all the time at work, smoothing 

 down the surface, and preventing the formation of scarps 

 along the lines of faulting. As Suessj remarks, " In 

 Bohemia, in the Palatinate, in Belgium, in Pennsylvania, 

 the plough often drives its furrows calmly across the most 

 powerful dislocations.'' Whatever the floor of our con- 

 tinents may be, it gives way frequently beneath us. A 

 wave passes through the crust, which has been racked 

 and strained ever since it first cooled upon the globe. 

 Our geographical boundaries first fluctuate, and are then 

 obliterated. The great trough and arch form themselves, 

 and remain stationary for what we call a geological 

 period. And so, with a delusive aspect of stability, on the 

 one hand a new ocean, on the other a continent, is born. 



MODERN ALCHEMY. 



By W. E. Ord, B.A. 



A LOVE of science for its own sake has been the 

 noblest incentive of the world's greatest dis- 

 coverers, but in the pursuit of chemical science 

 there has ever been an inducement of a more 

 practical kind. We find the alchemists of old 

 continually urged forward in their arduous labours by the 

 dreams of wealth which their science, if it could be so 

 called, appeared to render capable of realization ; or perhaps 

 by the infinite possibilities which seemed to exist in the 

 changing substances around them. In medisval times, 



* See lapworth, British Asf ce.Address, Nature, Tol. XLTI., p. 377. 



+ For a general surver of earth-moveirents in the Western States, 

 see C. E. Button, Sixth Ann.Bep. U.S.Geol. Siirreii (188.5), pp.183-198. 

 J " Das Antlitz derErde." Bd. I., p. 778. 



when the Europsan world was throbbing with the excite- 

 ment occasioned by the discovery of untold wealth in the 

 New World, when adventurers were giving their lives in 

 the vain endeavour to become rich at a stroke, the 

 alchemists in their laboratories were scarcely less eager in 

 their investigations, impelled by that dream of wealth 

 which never faOs to rouse the dormant energies of mankind. 

 Strange as the hope of the alchemists may seem to us, the 

 idea of transmuting the baser metals into gold appeared, 

 with the knowledge of chemistry then possessed, to have a 

 plausible foundation of fact. In the view of the alchemists, 

 the baser metals could have none of that stabflity of 

 character with which the pure elements are now associated. 

 Examined in an impure state, they were changeable in 

 their properties, and often unrecognizable, for a minute 

 trace of impurity alters their character. A trace of lead 

 or arsenic, for example, renders gold exceedingly brittle 

 and alters its colour ; while, as is well known, a small 

 quantity of carbon in iron causes it to become elastic, and 

 if more be present it becomes hard and brittle. In 

 addition to this instability of character, the transmutation 

 had every appearance of possibility under the view then 

 generally accepted — and first taught by Geber, an Arabian 

 chemist — that all the metals were alloys of sulphur and 

 mercury in varying proportions, their various properties 

 being produced by the existence of a greater or less 

 quantity of either of these elements. The noble metals 

 were held to be particularly rich in mercury and poor in 

 sulphur, and the transmutation of the baser metals was 

 thought to consist in the withdrawal of sulphur from them 

 and the addition of mercury. The difiiculties and con- 

 fusion which the alchemists had to contend with were 

 still further increased by the spirit of mysticism pervading 

 their writings, and the consequent impossibility of following 

 up the discoveries of previous investigators. In view of 

 such difficulties, it is not sm-prising that, though a belief 

 in alchemy lingered on into last century, the alchemists 

 should have bsen a long way from finding the true path to 

 a process of transmutation which is still regarded by many 

 as undiscoverable. 



Within the past year a claim has been made to the 

 discovery of a solution of the problem of the alchemists 

 which is both startling and interesting. Dr. Emmens, an 

 eminent chemist of New York City, and inventor of the 

 high explosive " Emmensite," has recently published an 

 account of some researches which would seem to have 

 resulted in the actual transmutation of silver into gold, 

 an achievement as important in its economic aspect as it 

 is revolutionary with regard to chemical theory. In order, 

 however, to properly appreciate the work which appears to 

 have been accomplished, it is well first to consider the 

 subject in the light of modern chemistry. The chemist, 

 in pursuing his analyses of matter as far as his methods 

 will permit, discovers that there are some seventy kinds 

 of substances which refuse to be split up into other sub- 

 stances, and to these ultimate constituents of matter he 

 gives the name of " elements.'' To the elementary bodies 

 he finds, by reason of certain considerations which cannot 

 cow be gone into, that different numbers, representing 

 the ratios of the weights of their respective atoms, may 

 be attached, and thus we obtain a series of elements with 

 atomic weights, ranging from that of hydrogen to those of 

 the heaviest elements known. It is, moreover, found (as 

 was first observed by Xewlands in 1864) that if the 

 elements are arranged in the order of their atomic weights, 

 similar elements recur at definite intervals in the series. 

 Thus they arrange themselves in several groups or 

 " natural families," and the properties of the elements 

 are said, mathematically, to be periodic functions of the 



