Society of Edinburgh, of which he was for many years Vice-President. He had already (in 1816) received half the French Institute's physical prize bestowed for two of the most important discoveries made in Europe during the two preceding years. In 1819, in conjunction with Professor Jamieson, he undertook the editing and publication of the Edinburgh Philosophical Journal, which he subsequently continued alone, through sixteen volumes, under the title of the Edinburgh Journal of Science. He was also, for many years and until his death, one of the editors of the London, Edinburgh, and Dublin Philosophical Magazine. In 1825 he was elected a corresponding member of the Institute of France; in 1830 he received the Royal Medal from the Royal Society of London, for his further discoveries in the polarization of light, and the same year received from William IV. the Guelphic Order, and the following year was knighted. From 1827 to 1833 he was engaged in investigations on the best methods of illumination for light-houses, and published a treatise on the subject, which led to the great improvements that have been made in lighthouses since that time. In 1833 he was chosen principal of the United Colleges of St. Leonard's and St. Salvator at St. Andrew's, which position he continued to hold till his death. In 1859 he was chosen as one of the eight foreign associates of the Institute of France, and, the same year, Principal and Vice-Chancellor of Edinburgh University. He was one of the prime movers in the organization of the "British Association for the Advancement of Science," and attended its annual sessions very regularly till within the last two years of his life. In 1857 he presided over its session at Edinburgh. Though not the discoverer of the principle of the stereoscope, he was the first to reduce it to practical uses. His improvements upon the construction of microscopes and telescopes were numerous and of great value to science. Among his other contributions to practical science were the initiation of the Bude Light, and his demonstration of the utility of dioptric lenses and of zones in lighthouses. Few men were as familiar as he with the profoundest secrets of natural science, yet no man of his time did as much to popularize it, and excite a thirst for scientific knowledge in the hearts of even the illiterate. His works on the "Kaleidoscope," "The Stereoscope," “Natural Magic,” "Martyrs of Science," "More Worlds than One" (a reply to Dr. Whewell's "Plurality of the Worlds"), his admirable "Life of Newton," and that long succession of brilliant and charming articles on scientific subjects in the North British Retie, and Popular Science Magazine, gave evidence of his disposition in this respect. He retained his intellectual and much of his physical vigor to the close of his life, and, though in his eighty-sixth year, came forward in the summer of 1867 and took an active part

in exposing the literary forgery of the pretended correspondence between Sir Isaac Newton and Pascal. Sir David was the last as he was one of the ablest of the great physicists of the last generation.

BRIDGES. Quincy Railway Bridge.-This bridge, crossing the Mississippi, and connecting with the Chicago, Burlington, Quincy, and the Hannibal and St. Joseph Railways, having just been completed, was opened for general traffic on the 7th of November. The design and execution were intrusted to Mr. T. C. Clarke, of Chicago. The part of the bridge crossing the main branch of the river, consists of two draw spans of 180 feet each, 11 spans of 157 feet each, 2 spans of 250 feet, 3 of 200 feet, 1,400 feet of embankment and trestle-work, and a smaller bridge 613 feet long, divided into one draw span 160 feet long, and four openings of 85 feet each, making the total length of the bridge and embankment from one railway to the other nearly two miles. The bridge is elevated 10 feet above high-water, and 20 feet above low-water mark, and the iron superstructure, on the Pratt-truss system, is supported on stone piers and abutments. The work was completed with unusual expedition, the first stone having been laid on September 25, 1867, and the bridge finished on the 5th of August, 1868. The total cost was $1,500,000.

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The bridge is so proportioned that, under the greatest loads, the utmost strain that can be brought upon it is 7.500 tons to the inch, the ultimate strength being 60,000 lbs. to the inch. In selecting the iron employed, all bars were tested up to a strain of 23,600 lbs. to the inch. The average quality of the material resisted a tension of 28,000 lbs. to the inch before a permanent set took place; some of the specimens broke under a strain of 80,000 lbs. The bridge before it was opened was subject to the following tests: Three of the heaviest locomotives upon the Chicago, Burlington, and Quincy Railroad, weighing together 300,000 lbs., were coupled together, and placed upon each of the 250-feet spans, in succession, and the deflection was accurately observed. The maximum deflection under this load was 24 inches, being less than one-sixteenth of the previous calculation. The same load was then placed upon a span 157 feet; the deflection in this case was 13 inches. The three locomotives, still coupled together, were then run backward and forward over the 157-feet span, at rates varying from 10 to 16 miles an hour. The deflection produced was 10 inches, or an inch more than was produced by the load when at rest. In every case the structure resumed its form when the engines were withdrawn, no permanent set being visible. On the 157-feet span the load applied was equivalent to a stress of 9,000 lbs. per square inch on the wrought iron, and 10,200 lbs.on the cast iron, or about one quarter more than the passage of the heaviest freight trains over the bridge can produce.

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of

Railway Bridge at India Point, Providence. -Soundings for this bridge were made to ascertain the nature of the river-bed, the depth of water, etc., in June, 1868. A good solid bottom was found, consisting of gravel, covered with a layer of mud, on top of which is a crust of oyster-shells, forming the river-bed. In the places where the piles were to be sunk, no obstructions were discovered, with the exception of the stump of an old pile, which was removed by the divers. On account of the soft, muddy layer of several feet in thickness, which covers the solid bottom, the piles were driven from temporary platforms. They were constructed of piles driven in four rows, about 20 feet into the bed of the river, and about 9 feet apart; these piles were capped with hard pine, about 13 inches square, and then covered with spruce plank. The permanent piles are arranged in clusters of 12 for the 2 piers west of the draw, and also 2 groups under the draw contain the same number. The other groups, five in number, contain 9 piles each. The piles were driven in the following manner: the first pile driven in was sharpened on all sides, the bevel commencing about 18 inches above the lower end, and the end left about 4 inches square; all the remaining piles, that presented only one side to those already driven, were sharpened only on one side, and the corner piles and those that were in contact with other piles were sharpened upon the two opposite sides. They are encased in cast-iron cylinders driven over them, the space between the piles and cylinders being firmly packed with concrete; the diameter of the cylinders west of the draw is 6 feet; the other 5 feet. The castings were made four and a half feet long, one and an eighth inches thick, having a flange four and five-eighths inches wide. The weight of the sections, as they came from the moulds, was, for those six feet in diameter, 5,459 pounds, and those five feet in diameter, 4,360 pounds. The rough castings were covered with a coating of cement, which attached itself firmly to the rough scale, thus forming a solid, durable covering; the sections were then firmly bolted together and carried by a scow to the platform, upon which they were hoisted, and from there forced down over the piles by means of a powerful screw-press. Notwithstanding the immense pressure brought to bear upon the cylinders, they were unable to penetrate the solid crust of oyster shells at the river-bed; the crust was then broken up by driving piles all around, and the cylinder again lowered; its weight alone, this time, carried it about four feet into the crust, and upon piling about ten tons of iron together, with continued rocking (accomplished by means of levers), the cylinder was finally forced home; all the others were sunk in a similar manner.

The capping of the piers west of the draw consists of yellow pine, that of the draw is formed of oak; the pier upon which the east end of the draw rests consists of granite,

twenty-two feet long, and six feet thick, resting on piles driven to a depth of thirty feet below the river-bed. The superstructure is of the ordinary form of Howe truss.

Bridge over the Alleghany. - The bridge of the Pittsburg, Fort Wayne, and Chicago Railroad, over the Alleghany River, is now completed. An interesting account of its construction we extract from the Pittsburg Ga zette: The original superstructure for double track was of wood, on the Howe-truss plan, with arches for additional strength, and consisted of seven spans of various lengths, being in all 1,172 feet long. On account of the peculiar form and location of the company's freightyard at Pittsburg, an additional pier 101 feet long was built on the wharf, under the first span on the Pittsburg side, and the abutment extended parallel with the river, along Duquesne Way, to 148 feet in length. By this arrangement the bridge opens gradually like a fan toward the Pittsburg freight-yard, being at the narrowest part, next to the main span, 55 feet in width, and extending out for 176 feet in length, to the point where it connects with the yard, where the width is 138 feet. For symmetry and economy in the construction, another pier was also built on the wharf at the Alleghany City end span of the bridge. At both of these end spans the tracks are now supported from below by girders, made entirely of plate and angle iron. The two western spans have each three girders 89 feet in length and 6 feet 6 inches deep, to support the double line of railway, the middle one being made proportionately stronger. On the two eastern spans, which form the above-mentioned addition to the yard, eighteen iron-plate girders, varying in length from 86 to 93 feet, all 6 feet 1 inch deep, are placed, distributed according to the tracks they are intended to support. The five large spans over the main part of the Alleghany River are built for a double line of railway, with one projecting footpath on the outside, consisting of three main girders, one on each side and one in the centre, between the ways. The average length of the spans is 153 feet in the clear, with a bearing of 5 feet on each pier. The depth of the girders is 19 feet. The clear width between the outside and the central girders is 14 feet, except the south part of the first main span, where it widens from 14 feet at one end to 32 feet at the other. The top and bottom sections of the girders are in the form of the letter T; the cross-sectional area of the top chord consists of 4 thicknesses of iron laid one over the other, well riveted, and forming together a plate 24 inches thick, and 24 inches wide in the centre part of the girder, and diminishing gradually to about twothirds its cross-section at the ends, where it rests on the piers. In addition to which there are 2 large angle-irons 5 inches by 33×3 inch to inch thick, and two vertical bars 12 inches by inch on the inside between the angle-iron, running along the centre of the horizontal

plates which form the top and bottom portion of the girders, to which they are attached by two of the angle-irons, the other two serving to join the flanges to the bars, which form the vertical web. The cross-sectional area of the bottom chords consists of three thicknesses of iron, well riveted, forming together a plate, in the centre part 24 inches thick, and 27 inches wide, the balance of the construction being similar to the top chord. The vertical web is composed of lattice-work, which is framed with two sets of bars six inches wide, crossing each other and inclined to the top and bottom at an angle of 48 degrees, and forming a network, the distance of the crossing apart being 2 feet 1 inch between the centres of the rivets, measured along the bars, the thicknesses of the bars increasing from inch at the centre part, to inch at the ends of the girders. They are secured at their crossings by two rivets. The lattice-work is stiffened by vertical angle-irons fixed double on both sides, at distances of about 8 feet apart. The central girder has about onethird more iron in the cross-section than the outside girders. The principle of the construction is known as the latticed-girder plan with vertical stiffenings.

Bridge Strains.-Mr. W. Airy has invented and applied a very novel and ingenious method of determining bridge strains. The problem was on the determination of the strains on every one of the intermediate bars connecting the top and bottom members of a bowstring bridge as ordinarily constructed, the said strains being those due to various arrangements of weights upon the bridge. To solve this problem practically, Mr. Airy has availed himself of the sense of hearing, or rather of comparison of musical sounds. It is well known that a steel wire, if stretched and sounded, will give forth a note dependent on its weight, length, and tension. If, therefore, two wires of the same steel, and of equal lengths, and at equal tensions, are sounded, they will give forth the same note, and, conversely, if they give forth the same musical note, it is to be inferred that the tensions are equal. In order to turn this principle to account, a model of a bowstring girder was constructed with great care, of which the intermediate ties were of thin steel wire. If, therefore, a load were hung from the string, these ties would at once go into tension, and each one, if sounded, would give forth a musical note due to its length and tension. To determine this tension, a wooden frame was constructed, and in this frame was hung a wire of the same steel as the ties; a sliding bridge was provided by which the wire could be cut off to any required length, by merely leaning against the bridge, and a small scale-pan was fastened to the end of the wire. This frame was moved close up to the model, and the wire in the frame being cut off by the bridge to the exact length of any one of the ties, the scalepan was gradually loaded with weights till the VOL. VIII.-6 A

musical note of the monochord exactly coincided with the note of the tie under comparison. In this condition, since the two wires are of the same steel and of the same length, and give forth the same musical note, their tensions are equal, and the weight in the scalepan is the tension of the tie. In this way every tension was determined separately and independently. Mr. Airy reckons that he determined all the tensions on his model to the extent of th part of the whole tension of each.

An ingenious artifice was employed to eliminate the unavoidable errors of original adjustment of the wires, and at the same time to obtain expressions for the strains of thrust as well as strains of tension; it is clear that there must be errors of original adjustment of the wires, for, even if it were possible so to adjust the lengths of the wires that each should have the strain due to a certain disposition of load, yet this very condition assumes that the problem is already solved, and that we know the exact strain that each wire ought to have; consequently, the determination of the strains is throughout a differential process: a certain load is laid upon the model, and each wire acquires a degree of tension, the precise amount of which is determined by the method of comparison with the monochord; these tensions are booked, and an additional load is then introduced; this will cause an alteration of the tensions on every wire, and the tensions of all are again taken. The differences of the tensions, before and after the introduction of the additional load, are formed for every wire, and these represent the strains on the wires due to the additional load only. The same process determines also the strains of thrust, for thrust is but negative tension, and if the tension of a wire, after the additional load is introduced, be less than it was previously, the difference is negative, and represents a thrust strain of that amount on that wire.

Mr. Airy also discovered a ready method for throwing all the wires into tension, by a uniform distribution of the preliminary load along the whole length of the model.

BROOKE, Sir JAMES, K. C. B., D. C. L., Rajah of Sarawak, and Governor of Labuan, an English knight-errant, philanthropist, and governor, whose love of adventure made his career one of the most remarkable of modern times, born in Bandel, Zillah Hoogly, Bengal, in 1803; died at Burrator, Devon, June 11, 1868. His father, who was a government officer of considerable wealth and prominence, returned to England when James was a child,. and he received his education there. His father's influence secured him a cadetship in the East-Indian army, and he soon distinguished himself by his bravery and daring. He was in most of the engagements of the Burmese War, under Sir Archibald Campbell, but in the storming of a stockade, in 1826, received a severe gunshot wound in the chest, and was forced to return to England for surgical treat

ment. Having recovered, he was ordered to report for duty in India, but, his furlough being extended, he travelled for a time on the Continent, and, being shipwrecked on his voyage to India, did not reach headquarters till some time after its expiration. Finding that he had thrus forfeited his position in the army, he resigned, and sailed from Calcutta, for China, in 1830. Observing the condition of the islands of the Indian Archipelago, and the prevalence of piracy there, he formed the determination to attempt the improvement of their condition. Returning to Europe in 1834, after the death of his father, he purchased one of the yachts of the Royal Yacht squadron, and, selecting a crew with great care, whom he drilled thoroughly in a preliminary cruise in the Mediterranean, he sailed from London, in October, 1838, for the East. Arriving at Sarawak, a province on the northwest coast of Borneo, he found Muda Hassim, the uncle of the Sultan of Borneo, and acting Rajah of the province, carrying on an unequal contest with rebel tribes from the interior, who descended in large bands upon his territory to plunder and lay it waste. He promptly offered his assistance, and, with his guns and trained troops, soon punished the rebels so severely that they were glad to make peace. Muda Hassim at once prompted his nephew to offer the Englishman the rajahship and make him absolute governor of the province. Mr. Brooke accepted the appointment, and, selecting a council of intelligent Dyaks to aid him in administering the government, he commenced a series of reforms which, carried out through many years, entitled him to be regarded as the greatest benefactor of the native population of Borneo. He would not suffer the people of Sarawak to be taxed for his support, but maintained himself upon his own income, and the rewards paid by the British Government for the suppression of piracy. His people had been a nation of pirates, but, by attaching the native rulers to himself by his astute measures for their welfare, and by making war upon pirates a pastime, he succeeded, in a few years, in clearing the entire archipelago of its bands of freebooters. He accustomed his people to the strict execution of justice, suffered no bribes to be given, was as accessible to the lowest and humblest of bis subjects as to the mightiest; encouraged industry, commerce, and such manufactures as they were capable of producing, and so won the love of his people, that they almost paid him divine honors. The jealousy of some of the officials of the East India Company was excited, by the independence of the Rajah; they coveted his territory, and desired to squeeze from the natives the revenue which Rajah Brooke had so nobly refused, and hence they were loud in their clamors against him, to the English Government, to which he was really not responsible. Waiving his rights in the matter, however, Mr. Brooke visited England, in 1847, and courted the most thorough

investigation of his conduct. This resulted in a complete approval, in his receiving the honor of being created Knight Commander of the Order of the Bath, and a baronetcy, and of his appointment as Governor of the island of Labuan, near Sarawak (which had been purchased by the British Government), with a salary £2,000. He still retained his office as Rajah of Sarawak. He returned to his Dyaks and prosecuted, with even more zeal than before, his measures for their improvement and elevation. The port of Sarawak, which at his first visit contained but 1,000 inhabitants, had risen, under his management, to a population of 25,000, and its exports from £25,000 to more than £300,000. He compiled laws, coined money, made roads, established schools, raised a regular revenue, and provided for the security of persons and property, and the strict administration of justice. But his enemies were still unsatisfied. Taking advantage of a change of administration, they procured his removal from the governorship of Labuan, thwarted his projects for making the ports of Borneo free to British vessels, and professed the utmost horror at the strictness of his rule over the lawless and thievish tribes of the interior, and the Chinese pirates, who began again to make their appearance on the coast of Borneo. The attachment of his people was strikingly manifested in 1857, when he was suddenly attacked in his house, at night, by a band of about 4,000 Chinese pirates and opium-smugglers, who hated him for his interference with their nefarious business. They burned his house, destroyed his gardens, and committed terrible havoc with his property, and he was compelled to save his own life by swimming. In the early morning, however, he had collected his faithful Dyaks, who were almost frantic with grief for the losses which the Chinese had inflicted upon him, and, leading them in person, attacked the Chinese, defeated them in several successive fights, and drove them into the jungle, with a loss of over 2,000 killed. The next year he returned to England again, and though a public subscription was made, amounting to a large sum, to reimburse his losses at Sarawak, yet the bitter attacks made upon him by his enemies in Parliament distressed him, and probably induced a paralytic attack, from which he suffered that year. He made his residence thenceforward in Burrator, Devon, but in 1861 made two voyages to Borneo, for the purpose of suppressing an insurrection, and settling the government, which he afterward left in charge of his nephew, though he retained the title and authority of Rajah till his death. Portions of his journals have been published, and also "The Private Letters of Sir James Brooke, K. C. B., from 1838 to 1853," edited by J. C. Temples, Esq., in three vols., London, 1853.

BROUGHAM, HENRY, Lord BROUGHAM AND VAUX, a British statesman and reformer, Lord

Chancellor of England 1830-1834, born in Edinburgh, September 19, 1778; died in Cannes, France, May 9, 1868. His father, Henry Brougham, was the descendant of an ancient family in Westmoreland, and his mother, Eleonora Syme, was a niece of Robertson the historian. Young Brougham was afforded excellent advantages of education, receiving his early training in the Edinburgh High School, and being transferred at an early age to the University. He was particularly fond of mathematical studies, and at the age of eighteen or nineteen communicated to the Royal Society of Edinburgh three mathematical papers which possessed such merit as to be published in the Society's Transactions. He was, even at that age, a proficient in the highest branches of mathematical science; and late in life he often avowed the opinion that he had mistaken his calling; that he should have devoted his life to mathematical studies, and that in them he might have surpassed all previous mathematicians. After taking his first degree at the University, he spent some time in travelling on the Continent, and in 1800 was admitted to the Scotch bar. He became about this time a member of the "Speculative Club," an association for the discussion of metaphysical and political questions, and was then brought into intimacy with Jeffrey, Horner, and Sydney Smith, with whom in 1802 he participated in the establishment of the Edinburgh Review, to which from its commencement he was a constant contributor, and the writer of some of its most powerful and caustic articles. So versatile were his talents, and so wide the range of his knowledge, that no subject came amiss to him. He was equally at home in physical and mathematical science, history, biography, literary criticism, and politics, and even plunged into the more recondite investigations of the medical and surgical professions. With two classes of topics, however, he did not interfere, theology and poetry. For neither of these had be any predilection. He displayed marked ability as an advocate, but his known liberal opinions imbittered the Tories, who were largely in the majority, against him, and the character he had acquired for eccentricity and indiscretion prevented his attaining a large practice, except in the unremunerative work of the criminal courts. In 1807, he was retained as one of the counsel in the case of the disputed succession of the dukedom of Roxburgh before the House of Lords. His argument in this case was one of his finest efforts, and attracted the attention of the nation to the eloquent Young advocate, who, yet under thirty years of age, could bring such learning, research, and legal ability to such a cause. Encouraged by the warmth of his reception in London, and despairing of any speedy success in Scotland, Brougham now resolved to remove to the metropolis, and was called to the bar at Lincoln's Inn in 1808. He rose rapidly in his profession, and soon acquired a large and lucrative

practice in the common law courts, and in the northern circuit. He was employed in the winter of 1809-'10 by some Liverpool merchants to bring their grievances before the House of Commons, and ask for the repeal of the Orders in Council, and in his advocacy of their cause displayed such eloquence and legal ability, that he attracted public notice, and became a distinguished favorite of the leading Whigs, who caused his election to Parliament the same year for the pocket borough of Camelford. In Parliament his vehemence in debate, his aggressive zeal, his caustic wit, and unsparing sarcasm, combined with a remarkable and convincing eloquence, made him a welcome and valued addition to the Whig force, and a formidable opponent to the Tories. He associated himself with the most advanced Whigs, and proved a valuable recruit to Wilberforce and Clarkson, who had been, for years, struggling against the slave-trade. Within a few months after entering Parliament, he had carried the first public measure he proposed, that of making the slave-trade a felony. He was unceasing in his attacks upon the measures of the Tory Government, and in 1812 succeeded in carrying the repeal of the obnoxious Orders in Council. He had also successfully defended Leigh Hunt, the poet-editor, against a libel prosecution instituted by the Government. He had advocated Catholic emancipation, reform in the government of India, and the abolition of flogging in the army. At the general election in 1812, he boldly contested (in company with another Whig) the membership for Liverpool, against Mr. Canning and his Tory associate. But the great Tory minister was too strong in Liverpool to be beaten, and Brougham and his friend were defeated. In a subsequent canvass for a seat from Scotland, he was also defeated, and remained out of Parliament till 1816, when he was returned for Winchelsea, and again became an opposition leader. He signalized his return to the House of Commons also by a movement of inquiry into the state of education of the poor in the metropolis, which he followed, in 1818, by procuring the appointment of a commission to inquire into the abuses of the public charitable foundations of the kingdom connected with education. These efforts for the improvement of the schools and the establishment of a system of national education were never intermitted until the end sought was gained. He had acquired by this time also a high reputation as an advocate in the defence of persons prosecuted for libel or other offences by the crown. His most famous appearance in this capacity was in 1820 and 1821, when, associated with Lord Denman, he undertook the defence of Queen Caroline against the charges of the King, before the House of Lords. Both the eminent counsel knew that the result would be their exclusion for years to come from all professional advancement; but Brougham's defence was bold, able, eloquent,