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born in 1791. Mr Faraday was a bookseller's apprentice, ‘very fond of experiment, and very averse to trade. He had attended Sir Humphry Davy's lectures and taken notes, which he transmitted to Sir Humphry, desiring his assistance to “escape from trade and enter into the service of science.’ Through Davy's exertions, he was appointed chemical assistant in the Royal Institution, 1813. His Researches on Electricity were published in 1831. In the application of electricity to the arts, MR CHARLES WHEATSTONE-born at Gloucester in 1802 —has been highly distinguished. The idea of the electric telegraph had been propounded in the last century, but it was not practically realised until the year 1837. The three independent inventors are Mr Morse of the United States, M. Steinheil of Munich, and Mr Wheatstone. Of these, the last has shewn the greatest perseverance and skill in overcoming difficulties. To Mr Wheatstone we also owe the invention of the stereoscope—that beautiful accompaniment to art and nature. Professor Forbes says: ‘Although Mr Wheatstone's paper was published in the Philosophical Transactions for 1838, and the stereoscope became at that time known to men of science, it by no means attracted for a good many years the attention which it deserves. It is only since it received a convenient alteration of form—due, I believe, to Sir David Brewster—by the substitution of lenses for mirrors, that it has become the popular instrument which we now see it, but it is not more suggestive than it always was of the wonderful adaptations of the sense of sight.’

DR BUCKLAND-SIR CHARLEs LYELL, ETC.

Geology has had a host of discoverers and illustrators. One of the earliest of English geologists was MR WILLIAM SMITH, who published his Tabular View of the British Strata in 1790, and constructed a geological map of England in 1815. He had explored the whole country on foot. The first of the prize-medals of the Geological Society was awarded to that gentleman in 1831, ‘in consideration, as stated, ‘of his being a great original discoverer in English geology, and especially for his having been the first in this country to discover and to teach the identification of strata, and to determine their succession by means of their imbedded fossils.” The REv. DR BUCKLAND (1784– 1856), by his Vindicia, Geologicae, 1820, and Reliquiae Diluviana, 1823, and by various contributions to the Geological Society, awakened public interest to the claims of this science, although he adhered to the old hypothesis of the universality of the deluge, which he abandoned in his Bridgewater Treatise of 1836. His Geology and Mineralogy was reprinted in 1858, with additions by Professors Owen and Phillips, and a memoir of the author by his son,

* This, however, had been clearly indicated more than a century before by the mathematician and natural philosopher, Da Robert Hoor E (1635-1703). In a lecture dated 1688, and published in Hooke's posthumous works, there occurs this , striking prophetic passage: “However trivial a thing a rotten shell may appear to some, yet these monuments of nature are more certain tokens of antiquity than coins or medals, since the best of those may be counterfeited or made by art and design; * * and though it must be granted that it is very difficult to read them—the records of nature—and to raise a chronology out of them, and to state the intervals of time wherein such or such catastrophe and mutations have happened, yet it is not impossible."—See Lyell's Principles, vol. i., in which the history of geological science is traced. Also Conybeare's Outlines of the Geology of England and Wales.

Mr Francis T. Buckland. The indomitable energy of Buckland, in pursuing his researches and collecting specimens of organic remains, is brought out fully in this memoir, with an account of his exertions to procure the endowment of a Readership in Geology at Oxford, which he accomplished in 1819.

Dr Buckland.

His invaluable museum he bequeathed to the university. It may be noted, also, that the glacial theory, illustrated by Agassiz and Professor James Forbes, was first promulgated by Dr Buckland, who travelled over the north of England and the wilds of Scotland for proofs of glacial action. Sir Robert Peel rewarded the labours of this ardent man of science by procuring his appointment to the deanery of Westminster. In its now revised and improved form, with additional plates of organic remains, Buckland's Geology and Mineralogy is the best general work on this interesting study. Previous to its first publication, Mr, now SIR CHARLEs LYELL, had published Principles of Geology, being an Attempt to Explain the former Changes of the Earth's Surface by a Reference to Causes now in Operation, two volumes, 1830–32. Additions and corrections have been made from time to time, and the eighth edition of the Principles, entirely revised, 1850, is a very complete and interesting work. But though introducing recent facts, Sir Charles still adheres to his original theory, that the forces now operating upon and beneath the earth's surface, are the same both in kind and degree with those which, at remote epochs, have worked out geological revolutions; or, in other words, that we may dispense with sudden, violent, and general catastrophes, and regard the ancient and present fluctuations of the organic and inorganic world as belonging to one continuous and uniform series of events. In 1888 Sir Charles published his Elements of Geology, since enlarged to two volumes. He is author also of Travels in North America, with Geological Observations on the United States, Canada, and Nova Scotia, two volumes, 1845, and Second Visit to the United States of America in 1845, two volume's". These are agreeable as well as instructive volumes, for Sir Charles is an accomplished literary artist, without betraying art in his composition.

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[Geology Compared to History.]

We often discover with surprise, on looking back into the chronicles of nations, how the fortune of some battle has influenced the fate of millions of our contemporaries, when it has long been forgotten by the mass of the population. With this remote event, we may find inseparably connected the geographical boundaries of a great state, the language now spoken by the inhabitants, their peculiar manners, laws, and religious opinions. But far more astonishing and unexpected are the connections brought to light, when we carry back our researches into the history of nature. The form of a coast, the configuration of the interior of a country, the existence and extent of lakes, valleys, and mountains can often be traced to the former prevalence of earthquakes and volcanoes in regions which have long been undisturbed. To these remote convulsions, the present fertility of some districts, the sterile character of others, the elevation of land above the sea, the climate, and various peculiarities, may be distinctly referred. On the other hand, many distinguishing features of the surface may often be ascribed to the operation, at a remote era, of slow and tranquil causes—to the gradual deposition of sediment in a lake or in the ocean, or to the prolific increase of testacea and corals. To select another example; we find in certain localities subterranean deposits of coal, consisting of vegetable matter formerly drifted into seas and lakes. These seas and lakes have since been filled up; the lands whereon the forests grew have disappeared or changed their form; the rivers and currents which floated the vegetable masses can no longer be traced; and the plants belonged to species which for ages have passed away from the surface of our planet. Yet the commercial prosperity and numerical strength of a nation may now be mainly dependent on the local distribution of fuel determined by that ancient state of things. Geology is intimately related to almost all the physical sciences, as history is to the moral. A historian should, if possible, be at once profoundly acquainted with ethics, politics, jurisprudence, the military art, theology; in a word, with all branches of knowledge by which any insight into human affairs, or into the moral and intellectual nature of man, can be obtained. It would be no less desirable that a geologist should be well versed in chemistry, natural philosophy, mineralogy, zoology, comparative anatomy, botany; in short, in every science relating to organic and inorganic nature. With these accomplishments, the historian and geologist would rarely fail to draw correct philosophical conclusions from the various monuments transmitted to them of former occurrences. They would know to what combination of causes analogous effects were referrible, and they would often be enabled to supply, by inference, information concerning many events unrecorded in the defective archives of former ages. But as such extensive acquisitions are scarcely within the reach of any individual, it is necessary that men who have devoted their lives to different departments should unite their efforts; and as the historian receives assistance from the antiquary, and from those who have cultivated different branches of moral and political science, so the geologist should avail himself of the aid of many naturalists, and particularly of those who have studied the fossil remains of lost species of animals and plants. The analogy, however, of the monuments consulted in geology, and those available in history, extends no further than to one class of historical monuments—those which may be said to be undesignedly commemorative of former events. The canoes, for example, and stone hate: found in our peat-bogs, afford an insight into 5.

the rude arts and manners of the earliest inhabitants of our island; the buried coin fixes the date of the reign of some Roman emperor; the ancient encampment indicates the districts once occupied by invading armies, and the former method of constructing military defences; the Egyptian mummies throw light on the art of embalming, the rites of sepulture, or the average stature of the human race in ancient Egypt. This class of memorials yields to no other in authenticity, but it constitutes a small part only of the resources on which the historian relies, whereas in geology it forms the only kind of evidence which is at our command. For this reason we must not expect to obtain a full and connected account of any series of events beyond the reach of history. But the testimony of geological monuments, if frequently imperfect, possesses at least the advantage of being free from all suspicion of misrepresentation. We may be deceived in the inferences which we draw, in the same manner as we often mistake the nature and import of phenomena observed in the daily course of nature, but our liability to err is confined to the interpretation, and, if this be correct, our information is certain.

[The Great Earthquake of Lisbon in 1755.]

In no part of the volcanic region of Southern Europe has so tremendous an earthquake occurred in modern times as that which began on the 1st of November 1755 at Lisbon. A sound of thunder was heard underground, and immediately afterwards a violent shock threw down the greater part of that city. In the course of about six minutes, sixty thousand persons perished. The sea first retired and laid the bar dry; it then rolled in, rising fifty feet above its ordinary level. The mountains of Arrabida, Estrella, Julio, Marvan, and Cintra, being some of the largest in Portugal, were impetuously shaken, as it were, from their very foundations; and some of them opened at their summits, which were split and rent in a wonderful manner, huge masses of them being thrown down into the subjacent valleys. Flames are related to have issued from these mountains, which are supposed to have been electric; they are also said to have smoked; but vast clouds of dust may have given rise to this appearance. The most extraordinary circumstance which occurred at Lisbon during the catastrophe, was the subsidence of a new quay, built entirely of marble at an immense cxpense. A great concourse of people had collected there for safety, as a spot where they might be beyond the reach of falling ruins; but suddenly the quay sank down with all the people on it, and not one of the dead bodies ever floated to the surface. A great number of boats and small vessels anchored near it, all full of people, were swallowed up as in a whirlpool. No fragments of these wrecks ever rose again to the surface, and the water in the place where the quay had stood is stated, in many accounts, to be unfathomable; but Whitehurst says he ascertained it to be one hundred fathoms. In this case, we must either suppose that a certain tract sank down into a subterranean hollow, which would cause a ‘fault' in the strata to the depth of six hundred feet, or we may infer, as some have done, from the entire disappearance of the substances engulfed, that a chasm opened and closed again. Yet in adopting this latter hypothesis, we must suppose that the upper part of the chasm, to the depth of one hundred fathoms, remained open after the shock. According to the observations made at Lisbon, in 1837, by Mr Sharpe, the destroying effects of this earthquake were confined to the tertiary strata, and were most violent on the blue clay, on which the lower part of the city is constructed. Not a building, he says, on the secondary limestone or the basalt was injured. The great area over which this Lisbon carthquake extended, is very remarkable. The movement was most violent in Spain, Portugal, and the north of Africa; but nearly the whole of Europe, and even the West Indies, felt the shock on the same day. A sea- | port called St Ubes, about twenty miles south of Lisbon, was engulfed. At Algiers and Fez, in Africa, the agitation of the earth was equally violent; and at the distance of eight leagues from Morocco, a village with the inhabitants, to the number of about eight or ten thousand persons, together with all their cattle, were swallowed up. Soon after, the earth closed again over them. The shock was felt at sea, on the deck of a ship to the west of Lisbon, and produced very much the same sensation as on dry land. Off St Lucar, the captain of the ship Nancy felt his vessel so violently shaken, that he thought she had struck the ground, but, on heaving the lead, found a great depth of water. Captain Clark, from Denia, in latitude 36° 24' N., between nine and ten in the morning, had his ship shaken and strained as if she had struck upon a rock. Another ship, forty leagues west of St Vincent, experienced so violent a concussion, that the men were thrown a foot and a half perpendicularly up from the deck. In Antigua and Barbadoes, as also in Norway, Sweden, Germany, Holland, Corsica, Switzerland, and Italy, tremors and slight oscillations of the ground were felt. The agitation of lakes, rivers, and springs in Great Britain was remarkable. At Loch Lomond, in Scotland, for example, the water, without the least apparent cause, rose against its banks, and then subsided below its usual level. The greatest perpendicular height of this swell was two feet four inches. It is said that the movement of this earthquake was undulatory, and that it travelled at the rate of twenty miles a minute. A great wave swept over the coast of Spain, and is said to have been sixty feet high at Cadiz. At Tangier, in Africa, it rose and fell eighteen times on the coast; at Funchal, in Madeira, it rose full fifteen feet perpendicular above high-water mark, although the tide, which ebbs and flows there seven feet, was then at half-ebb. Besides entering the city and committing great havoc, it overflowed other seaports in the island. At Kinsale, in Ireland, a body of water rushed into the harbour, whirled round several vessels, and poured into the market-place. It was before stated that the sea first retired at Lisbon ; and this retreat of the ocean from the shore at the commencement of an earthquake, and its. subsequent return in a violent wave, is a common occurrence. In order to account for the phenomenon, Michell imagined a subsidence at the bottom of the sea from the giving way of the roof of some cavity, in consequence of a vacuum produced by the condensation of steam. Such condensation, he observes, might be the first effect of the introduction of a large body of water into fissures and cavities already filled with steam, before there had been sufficient time for the heat of the incandescent lava to turn so large a supply of water into steam, which, being soon accomplished, causes a greater explosion.

Sir Charles Lyell is a native of the county of Forfar, son of a landed proprietor there, and was born in 1797. He studied at Exeter College, Oxford, and afterwards was called to the bar. In 1836 he was elected President of the Geological Society, and the same honour was again conferred upon him in 1850–51. He was knighted in 1848.

Geological Notes and Sections were published in 1830 by SIR HENRY THoMAs DE LABECHE (1796– 1855), and in 1832 a Manual of Geology. But his most valuable work is How to Observe: Geology, 1835. In 1851 Sir Henry published another work of the same kind, The Geological Observer. DR GIDEoN

ALGERNoN MANTELL (1788–1852), an English 100

physician, in 1832 published The Fossils of the South Downs, which appeared simultaneously with the

Sir Henry Thomas De La Beche.

great work of Cuvier and Brongniart on the Geology of the Environs of Paris, and described also many of the organic remains of the chalk. Dr Mantell was the original demonstrator of the fresh-water origin of the mass of Wealden beds, and the discoverer of the monster reptile Iguanodon, and other colossal allies. This eminent palaeontologist was author of two popular works—The Medals of Creation, and The Wonders of Geology. DR John PYE SMITH (1774–1857), in his work On the Relation between the Holy Scriptures and some parts of Geological Science, 1839, and the distinguished American geologist, DR EDwARD HITCHcock, in his Elementary Geology, 1841, anticipated the views of Hugh Miller and others as to the interpretation of the Mosaic account of the creation and deluge—the latter being local, not universal. With respect to the deluge, Dr Pye Smith forcibly remarks: “All land-animals having their geographical regions, to which their constitutional natures are congenial-many of them being unable to live in any other situation—we cannot represent to ourselves the idea of their being brought into one small spot from the polar regions, the torrid zone, and all the other climates of Asia, Africa, Europe, and America, Australia and the thousands of islands—their preservation and provision, and the final disposal of them-without iringing up the idea of miracles more stupendous than any that are recorded in Scripture.'

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classify these rocks, and after four years labour, he assigned to them (1835) the name of the Silurian System, as occupying the ancient Roman province of Siluria. “Having first, in the year 1833, says Sir Roderick, “separated these deposits into four formations, and shewn that each is characterised by peculiar organic remains, I next divided them (i834–35) into a lower and upper group, both of which, I hoped, would be found applicable to wide regions of the earth. After eight years of labour in the field and the closet, the proofs of the truth of these views were more fully published in the work entitled The Silurian System, 1839. A further explanation of this system, embodying later researches, was published by the author in 1854, entitled Siluria, the History of the Oldest Known Rocks containing Organic Remains.

[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 a former sea, all of which have been derived from pre-existing rocks; and in these 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 strata 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 shew 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 rocks of the deposits termed Silurian.

In France, Germany, Spain, and the Mediterranean, in Scandinavia and Russia, the same basis has been found for higher fossiliferous rocks. Many years were spent by Sir Roderick, accompanied part of the time by Professor Sedgwick, in Russia and other countries in geologic explorations; and in 1846 he published The Geology of Russia in Europe and the Ural Mountains, in which he was assisted by E. de Verneuil and Count A. von Keyserling. Sir Roderick is author of about a hundred separate memoirs, presented to scientific societies, and he had the merit of pointing out the important fact that gold must exist in Australia. This was in 1844, after inspecting some specimens of Australian rocks brought to this country by Count Streleczki, and comparing them with those of the auriferous Ural Mountains with which he was personally well acquainted. His observations were printed the same year (1844) in the journal of the Royal Geographical Society. Two years afterwards, at a geological meeting in Penzance, Sir Roderick urged the superabundant Cornish tin-miners to emigrate to the colony of New South Wales, and there obtain gold from the alluvial soil in the same manner as they extracted tin from the gravel of their native country. Again, in the year 1846, when some specimens of Australian gold ore were sent to him, he addressed a letter to Earl Grey, then secretary for the colonies, stating his views as to the existence of rich gold-fields in the colony." Sir Roderick also predicts (1854) that “the present large flow of gold into Europe from those tracts will begin to diminish Within a comparatively short period’—a result of which we have as yet no indication.

7* Hargrave's Australia and its Goldfields, 1855.

[The Relative Value of Gold and Silver.]

The fear that gold may be greatly depreciated in value relatively to silver—a fear which may have seized upon the minds of some of my readers—is unwarranted by the data registered in the crust of the earth. Gold is, after all, by far the most restricted—in its native distribution—of the precious metals. Silver and argentiferous lead, on the contrary, expand so largely downwards 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 difficulty of subterranean mining. It may, indeed, well be 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 a geologist; and I would simply say, that Providence seems to have originally adjusted the relative value 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 the silver. * * The earth hath dust of gold.’

Sir Roderick Murchison is by birth a Scottish Highlander, born at Tarradale, Ross-shire—of which his father, Dr Murchison, was proprietor—in 1792. He served from 1807 to 1816 in the army, latterly as captain in the 6th Dragoons. He was knighted in 1846, and the emperor of Russia conferred upon him the Grand Cross of the Order of St Stanislaus, with other marks of distinction.

PROFESSOR SED GW ICE.

The REv. ADAM SEDGwick has endeavoured to substantiate a lower and still older section of rocks than the Silurian—a slatyformation, in partfossiliferous, and of enormous thickness. He applies to this the term ‘Cambrian. The system has, however, met with a dubious acceptance, Sir Roderick Murchison contending that the Cambrian rocks are not inferior in position to the lowest stratified rocks of his Silurian region of Shropshire and the adjacent parts of Montgomeryshire, but are merely extensions of the same strata. Mr Sedgwick was born at Dent, Yorkshire, about the year 1787; in 1809 he was admitted to a Fellowship in Trinity College, Cambridge, and in 1818 was appointed Woodwardian Professor of Geology. He is author of A Synopsis of the Classification of the British Palaeozoic Rocks, &c., two volumes, quarto, and A Discourse on the Studies of the University of Cambridge, 1850, besides numerous contributions to scientific and literary journals.

PROFESSOR OWEN-DR CAR PENTERDR ELLIOTS ON.

One of the greatest of modern scientific names, associated also with public services for sanitary reform, is that of MR RICHARD OwRN, well known as the Hunterian Professor in the Royal College of Surgeons, and now superintendent of the department of natural history in the British Museum. In physiology and comparative anatomy, Professor Owen's works and contributions to journals and societies are very numerous. Among them are– Odontography, two volumes, 1840; History of British Fossil Mammals and Birds, 1846; British Fossil Reptiles, 1849–51; Lectures on the Comparative Anatomy of Vertebrate and Invertebrate Animals; Nature of Limbs, 1849; &c. Professor Owen is a native of Lancaster, born about 1803; he was appointed Hunterian Professor in 1835, and drew up elaborate catalogues of the physiological specimens and fossil organic remains preserved in the museum. In physiology, DR WILLIAM BENJAMIN CARPENTER has also earned distinction. His chief works are—Principles of General and Comparative Physiology, Principles of Human Physiology, Vegetable Physiology and Botany, Zoology and Instinct in Animals, Popular Cyclopaedia of Natural Science, seven volumes, Mechanical Philosophy, On the Microscope, &c. These works were produced between 1839 and 1854, and most of them have gone through several editions. Mr Morell, in his History of Modern Philosophy, has said that Dr. Carpenter's works “manifest some of the best qualities both of the thinker and the observer. The father of the physiologist, DR LANT CARPENTER (1780–1840), was a well-known Unitarian minister, and writer on education and theology. DR JoHN ELLIOTSON, a London physician, in 1840 published Human Physi

ology, and afterwards attracted attention by lectures on phrenology and mesmerism. He procured the establishment of a mesmeric hospital, and set up a periodical, The Zoist, in support of his physiological opinions. Mr Thackeray dedicates his novel of Pendennis to Dr Elliotson, in acknowledgment of his medical skill, “great goodness, and kindness,’ for which the physician would take no other fee but thanks.

HUGH MILLER.

As a popular illustrator of geology, no author approaches HUGH MILLER, the self-taught man of science and genius. He was, as is well known, a native of Cromarty, born October 10, 1802. He was of a race of sea-faring men well to do in the world, who owned coasting-vessels, and built houses in the town of Cromarty. One of them had done a little in the way of bucaneering on the Spanish main. Most of them perished at sea, including Hugh's father, who was lost in a storm in 1807. By the aid of two maternal uncles, Hugh received the common education of a Scottish country-school, and was put apprentice, by his own desire, to a stonemason. His sensations and geological discoveries while toiling in the Cromarty quarries are beautifully told in the opening chapters of his work on the Old Red Sandstone. A life of toil, however, in such a sphere as this has its temptations, and the drinking usages of the masons were at that time carried to some excess. Hugh learned to regard the ardent spirits of the dram-shop as high luxuries; they gave lightness and energy to both body and mind. “Usquebaugh, he says, “was simply happiness doled out by the glass and sold by the gill. Soon, however, his better genius prevailed.

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at present before me—a small edition of the Essays of Bacon, a good deal worn at the corners by the friction of the pocket—for of Bacon I never tired. The condition into which I had brought myself was, I felt, one of degradation. I had sunk, by my own act, for the time, to a lower level of intelligence than that on which it was my privilege to be placed; and though the state could have been no very favourable one for forming a resolution, I in that hour determined that I should never again sacrifice my capacity of intellectual enjoyment to a drinking usage; and, with God's help, I was enabled to hold by the determination. * * I see, in looking back on this my first year of labour, a dangerous point, at which, in the attempt to escape from the sense of depression and fatigue, the craving appetite of the confirmed tippler might have been formed.

This may be considered a grand era in the life of Miller. He had laid the foundation of a habit of virtuous self-denial and decision of character, that was certain to bear precious fruits. Removing to

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