cess, according to one principle. As knowledge broadens and wider generalizations are made, we find a certain likeness of process in all realms that indicates one law or method; namely, that of development or evolution. One thing comes from another, assumes a higher and a finer form, and presses steadily on toward still finer and higher forms. We find the same method in matter, in brute life, in humanity, in social institutions, in government, in religions, in the progress of Christianity. Let not this thought disturb us. Do we not see that otherwise the universe could have no unity? If God worked on one principle in the material realm, on another in the vital, on another in the social, governmental, and moral realm, there would not be a proper universe. These realms might, indeed, be regulated and kept from conflict, but they would break up the universe into parts separated by chasms, render knowledge difficult, vain, and disjointed, and create a certain antagonism opposite to the nature of mind. Man would be correlated, not to a universe, but to separate systems and orders, and these varied correlations would have no underlying unity. It would be difficult to prove the unity of God as against a harmonious polytheism or sovereign Jove. We might believe in one God, but we could not prove our faith. If matter has one principle in its process, and life another, and morals another, why not as many gods? It has not been easy to keep dualism out of philosophy. But with one principle or method in all realms, we have a key that turns all wards of the universe, opens all its doors in the past, and will open all in time to come. Knowledge becomes possible and harmonious; a path opens everywhere; the emphasis of the whole universe is laid on the unity of God.— The Appeal to Life.

D

URCHISON, SIR RODERICK IMPEY, a British geologist; born at Tarradale, Ross-shire, February 19, 1792; died at London, October 22, 1871. He obtained a commission in the army in 1807, served during a part of the Peninsular War, and retired in 1815, with the rank of captain of dragoons. By the Advice of Humphry Davy he devoted himself to the study of geology, and in 1825 read his first paper before the Geological Society. Shortly afterward he began a systematic examination of the lower fossiliferous rocks of England and Wales. He applied the name "Silurian" to a series of rocks intermediate between the Cambrian and Devonian formations. His most important work, The Silurian System, appeared in 1839, a revised edition of which was published in 1854 under the title Siluria. Between 1840 and 1844, at the invitation of the Emperor Nicholas, he made geological explorations over a considerable portion of the Russian empire, the results of which were embodied in his Geology of Russia-inEurope and the Ural Mountains (1845). In 1846 he was chosen President of the British Association, and in 1855 Director of the British Geological Survey. He was knighted in 1846, and created a baronet in 1866. He seems to have been the first to perceive the real configuration of the African continent.

THE LOWER SILURIAN ROCKS.

The geologist appeals to the book of nature, where its leaves have undergone no great alteration. He sees before him an enormous pile or series of early subaqueous sediment, originally composed of mud, sand, or pebbles, the successive bottoms of which have been de

rived from pre-existing rocks; and in those lower beds, even where they are little altered, he can detect no remains of former creatures. But lying upon them, and therefore evolved after, other states succeed in which some few relics of a primeval ocean are discernible; and these again are everywhere succeeded by newer deposits, in which many fossils occur. In this way evidences have been fairly obtained to show that the sediments which underlie the strata containing the lowest fossil remains constitute in all countries which have been examined the natural base or bottom-rock of the deposits named Silurian.- Siluria.

When, in 1854, the great accessions of gold from California and Australia were pouring in, Murchison predicted that "the present large flows of gold into Europe will begin to diminish within a comparatively short period"; and he gave his reasons for believing that the then existing relation between the values of gold and silver would never be changed. He says:

THE RELATIVE PRODUCTION OF GOLD AND SILVER.

The fear that gold may be greatly depreciated in value relatively to silver is unwarranted by the data registered in the crust of the earth. Gold is, after all, in its native distribution, by far the most restricted of the precious metals. Silver and argentiferous lead, on the contrary, expand so largely downward into the bowels of the rocks as to lead us to believe that they must yield enormous profits to the skilful miner for ages to come; and the more so in proportion as better machinery and new inventions shall lessen the difficulties of subterranean mining. It may, indeed, be well doubted whether the quantities of gold and silver procurable from regions unknown to our progenitors will prove more than sufficient to meet the exigencies of an enormously increased population and our augmenting commerce and luxury. But this is not a theme for the geologist; and I would simply say that Providence VOL. XVII.-15

seems to have originally adjusted the relative values of these two precious metals, and that their relations, having remained the same for ages, will long survive all theories. Modern science, instead of contradicting, only confirms the truth of the aphorism of the patriarch Job, which thus shadowed forth the downward persistence of the one, and the superficial distribution of the other: "Surely, there is a vein for silver. The earth hath dust of gold."

Of the character of Murchison's work his biographer, Professor Geikie, says:

"If it be true, as Bacon asserted, that 'writing maketh an exact man,' it is no less true that mapping makes an exact geologist. Murchison wisely resolved not to trust merely to eye and memory, but to record what he saw as accurately as he could upon maps. And there can be no doubt that by so doing he gave his work a precision and harmony that it could never have otherwise possessed, and that, even though still falling into some errors, he was enabled to get a firmer hold of the structure of the country which he had resolved to master than he could have obtained in any other way. For, to make his maps complete, he was driven to look into all manner of out-of-the-way nooks and corners, with which, but for that necessity, he might have been little likely to make acquaintance."

URE, WILLIAM, a British historian; born near Caldwell, Ayrshire, Scotland, July 9, 1799; died at London, April 1, 1860. He was educated at the University of Edinburgh; afterward studied in Germany, and made a visit to Greece. His earlier works are Chronology of the Egyptian

Dynasties (1829); Dissertation on the Calendar of the Zodiac of the Ancient Egyptians (1832); Journal of a Tour in Greece (1838). He was Lord Rector of the University of Glasgow in 1847-48, and represented Renfrewshire in Parliament from 1846 to 1855. His most important work, A Critical History of the Language and Literature of Ancient Greece (185057), was left unfinished at his death, having been. brought down to the time of Xenophon.

THE ORIGIN OF WRITING IN GREECE.

That the Hellenes were indebted for their first knowledge of the art of writing to the Phoenicians is a tradition, of the historical value of which we have historical proof altogether distinct from its own antiquity or universality in the characters of the Greek alphabet. In regard to the period at which a knowledge of these characters was first communicated to the Greeks, we are left as on other points of earliest Hellenic culture - altogether dependent on mythical sources. There are, however, few national legends which, on the twofold grounds of internal probability and the inveterate. conviction of the enlightened native public in its favor, can advance stronger claims to the character of historical fact that that which ascribes the introduction of the alphabet to the Oriental colonies, figured, in the name and person of the hero Cadmus, as having settled in Greece chiefly in Boeotiaat an early mythical period.

This legend is at least broadly distinguished by the above-mentioned more solid characteristics from various other traditions of mere local or poetical origins, invented in honor of certain heroes or tribes, and according to which there is scarcely a Greek patriarchal chief celebrated for ingenuity in the elementary sciences, to whom the discovery of this essentially Phoenician art has not been attributed. Such are Prometheus, Orpheus, Musæus, Linus, Chiron, Palamedes. There