Part 4

A short time before the termination of the war with France he devised a plan for making shoes by machinery, and under the countenance of the Duke of York the shoes so manufactured were introduced for the use of the army, on account of their strength, cheapness, and durability; but at the peace in 1815, the machines were laid aside, manual labour having become cheaper, and the demand for military equipments having in a measure ceased. Steam navigation also attracted Brunel's attention, and he became deeply interested in establishing the Ramsgate steam vessels, which were among the first that plied effectively on the River Thames. About this period, after much labour and perseverance, he induced the Admiralty to permit the application of steam for towing vessels to sea, the experiments being made chiefly at his own expense, a small sum in aid having been promised, but eventually withdrawn before the completion of the trials, the Admiralty considering the attempt too chimerical to be seriously entertained.

In the year 1824 Brunel, undeterred by the two previous failures of Dodd and Trevethick, commenced his great work--the Thames Tunnel. It is said that the original idea occurred to him as applied to the Neva at St. Petersburgh, in order to avoid the inconvenience arising from the floating ice; a plan which he offered to the Emperor Alexander, on the occasion of his visit to this country in 1814. During the above-mentioned year a company was formed for the execution of this work, under the auspices of the Duke of Wellington, who had always entertained a favourable view as to its practicability; and after numerous accidents, and frequent suspensions of the works, this great and novel undertaking was successfully accomplished, and opened to the public in the year 1843. In the prosecution of this undertaking Sir Isambard derived great assistance from his son, the late Mr. I. K. Brunel.

The shield, as it was termed, under shelter of which the excavation beneath the bed of the river was carried forward, required very peculiar contrivances to adapt it to its purpose. It was made in sections or compartments contained in a strong square frame, each section or compartment being moved forward by screws, as the men working in them proceeded with the excavation; the entire shield was thus enabled to be moved forward, and the brickwork, consisting of two tunnels, was built up to the extent that it had been advanced.

After the completion of the Tunnel, Brunel's health became seriously impaired from the labours he had undergone in its execution, and he was unable to mix in active life; he expired on the 12th of December, 1849, in his eighty-first year, after a long illness.

He received the honour of Knighthood in 1841, and the order of the Legion of honour in 1829; he was also a corresponding member of the French Institute, a Fellow of the Royal Society, and a member of the Institution of Civil Engineers, which he joined in the year 1823.--_Annual Report of the Institution of Civil Engineers._ December 17, 1850.--_Beamish's Life of Brunel._ London, 1862.

EDMUND CARTWRIGHT, D.D., F.R.S., &c.

Born April 24, 1743. Died October 30, 1823.

Dr. Cartwright, whose invention of the power-loom may be considered as one of the valuable elements of our national manufacturing superiority, was born at Marnham in Nottinghamshire, and was the youngest of three brothers, all of whom were remarkable men.[9] He was educated under Dr. Clarke, at the Grammar School of Wakefield, and had he been permitted to follow the bent of his own inclination in the choice of a profession, would have preferred the navy; but two of his brothers being already designed for that service, it was thought advisable that Edmund should enter the Church. Dr. Cartwright began his academical studies at University College, Oxford, where he was entered at fourteen years of age, and during the vacations was placed under the private tuition of Dr. Langhorne, the editor of 'Plutarch's Lives.'

In process of time he became distinguished for his literary abilities, and was elected a Fellow of Magdalen College. He likewise evinced a considerable taste for poetry, and published in 1770 a legendary tale, entitled 'Armine and Elvira,' which went through seven editions in little more than a year, and was greatly admired for its pathos and elegant simplicity. Some years subsequent to this, Cartwright wrote 'The Prince of Peace,' published in 1779, and was also for several years a principal contributor to the 'Monthly Review.'

In the year 1772 he married the daughter of Richard Whittaker, Esq., of Doncaster, and after his marriage resided first at Marnham, and afterwards at Brampton in Derbyshire, to the perpetual curacy of which he was presented by the Dean of Lincoln, Dr. Cust. It was while attending to his clerical duties at this latter place, that Cartwright discovered the application of yeast as a remedy for typhus fever. In 1779 he was presented to the living of Goadby Marwood in Leicestershire, and continued to reside there until the summer of 1796, when he removed with his family[10] to London, as being a situation more favourable for the cultivation of the scientific pursuits in which he had by that time become engrossed.

Dr. Cartwright had attained the mature age of forty, before his attention was drawn towards the subject of weaving, by the following accidental occurrence:--In the summer of 1784, he happened to be on a visit at Matlock, in Derbyshire, and in the company of some gentlemen from Manchester. The conversation turned upon Arkwright's spinning machinery; and fears were expressed by one of the company, that, in consequence of the recent improvements, so much cotton would soon be spun, that hands would not be found to weave it. To this the doctor replied, that the only remedy for such an evil would be to apply the power of machinery to weaving as well as spinning. The discussion which ensued upon the practicability of doing this, made such an impression on Cartwright's mind, that on returning home he determined to try and see what he could do.

His first attempts, as might be supposed, were very clumsy, but he at length succeeded in constructing a machine (for which he took out a patent in 1785), which, although rude and cumbersome in its action, was yet capable of weaving a piece of cloth. Up to this time he had never turned his mind to anything mechanical, either in theory or practice, and his invention was consequently susceptible of great improvement. To accomplish this, he now examined with care the contrivances already in use among the weavers, and availing himself of their general principles, produced in the year 1787 a far more complete and valuable machine, since known as the power-loom.

Shortly after he had brought his loom to perfection, a manufacturer who had called upon him to see it at work, after expressing his admiration at the ingenuity displayed in it, remarked, that wonderful as was Dr. Cartwright's skill, there was one thing that would effectually baffle him, and that was, the weaving of patterns in checks, or, in other words, the combining in the same web a pattern or fancy figure with the crossing colours which constitute the check. The doctor made no reply to this at the time; but some weeks afterwards, on receiving a second visit from the same person, he showed him a piece of muslin, of the description mentioned, beautifully executed by machinery, which so astonished the man, that he roundly declared his conviction that some more than human agency must have been called in on the occasion.[11]

Dr. Cartwright being precluded by his clerical character from entering himself into the manufacture of his machines, a weaving factory was erected at Doncaster, by some friends, with his licence, but it was unsuccessful; and another establishment, built at Manchester, containing 500 looms, was destroyed by an exasperated mob in 1790. Cartwright, however, still continued his inventions, and shortly afterwards contrived a wool-combing machine, which met with even fiercer opposition from the working-classes, who went the length of petitioning parliament to suppress all such obnoxious machines. Their great utility, however, caused them by degrees to be generally adopted; and at the time of Cartwright's death, steam-looms had increased so rapidly, that they were performing the work of 200,000 men.

Notwithstanding the great advantages which the cotton and wool manufacturers reaped from these inventions, their author had as yet obtained no emolument from them, but, on the contrary, had incurred a heavy loss. In consideration of this, and on the petition of several influential cotton-spinners, Parliament in 1810 made the doctor a grant of 10,000_l._--a sum which, although munificent as a present, hardly covered what he had expended in his experiments. Having received the sum awarded by Parliament, and being now sixty-six years of age, Dr. Cartwright was desirous of passing the remainder of his life in retirement and tranquillity, and for this purpose purchased a small farm at Hollenden, in Kent. At this place he spent the remainder of his life, occupied in various scientific and mechanical experiments.

Dr. Cartwright was the author of many other inventions in the arts and agriculture, for some of which he received premiums from the Board of Agriculture and Society of Arts. He also contrived an ingenious modification of the steam-engine, in which he made use of _surface condensation_, and metallic spring packing for the piston.

Till within a few days of his death, Dr. Cartwright retained full possession of his mental faculties, and attained, at the time of his decease in 1823, the age of eighty-one. His remains were interred in the church at Battle, in Sussex. _Memoir of Dr. Edmund Cartwright._ London, 1843.--_Stuart's Anecdotes of the Steam-Engine._ London, 1829.

THE HON. HENRY CAVENDISH, F.R.S.

Born October 10, 1731. Died February 24, 1810.

Henry Cavendish, the third in order of time among the four great English pneumatic chemists of the eighteenth century,[12] was the younger son of Lord Charles Cavendish, whose father was the second Duke of Devonshire. His family trace back their descent in unbroken and unquestionable links to Sir John Cavendish, Lord Chief Justice during the reign of Edward III. The great majority of the distinguished chemists of Great Britain have sprung from the middle and lower ranks of the people, but in this respect Henry Cavendish presents a remarkable exception. He was moreover immensely wealthy, so much so, that it has been epigrammatically remarked of him, "That he was the richest of all wise men, and probably, too, the wisest of all rich men;" yet no one could well be more indifferent than he, to the external advantages which are conferred by birth and fortune. Few particulars are known of his early life. He was born at Nice, whither his mother, who died when he was two years old, had gone for the sake of her health.

In 1742 Cavendish became a pupil at Dr. Newcome's school at Hackney, continuing his studies there until he had reached his seventeenth year, when he went to Cambridge, where he matriculated in the first rank on the 18th of December, 1749. He remained at this university until 1753, but did not graduate.

After leaving Cambridge, the personal history of Cavendish becomes a blank for the next ten years. He joined the Royal Society in 1760, but did not contribute anything to its 'Transactions' until the year 1766, when he published his paper 'On Factitious Airs,' which contains the first distinct exposition of the properties of hydrogen, and the first full account of those of carbonic acid; and a paper published by him in the following year may be considered as a still further extension of his research into the properties of this acid.

For some considerable time after this, Cavendish appears to have laid aside Chemistry for other departments of physics. In 1771 he published an elaborate paper on the theory of the principal phenomena of electricity; and in 1776 appeared the curious and interesting account of his attempts to imitate the effects of the torpedo, by an apparatus constructed in imitation of the living fish, and placed in connection with a frictional electrical machine and a Leyden battery. In this imitation he succeeded so well, that all doubts were removed as to the identity of the torpedinal benumbing power with common electricity. In 1776 Cavendish was selected by the Royal Society, in whose 'Transactions' all his previous papers had been published, to describe the various meteorological instruments which were made use of in their apartments; and the succeeding year to this marks the period when he commenced his most important chemical researches, entitled 'Experiments on Air,' which were carried on with frequent and sometimes long interruptions until 1788, no part of them, however, having been published before the year 1783. They led to the discovery of the constant quantitative composition of the atmosphere, the compound nature of water, and the composition of nitric acid. To solve the important problems, whether the atmosphere is constant in its composition, and if so, what is its composition? Cavendish experimented in 1781 for some sixty successive days, making many hundred analyses of air. The honour of the discovery of the compound nature of water, by which perhaps his name has become most famous, is also claimed by James Watt. Cavendish, however, seems at all events entitled to the honour of having first supplied the data on which that discovery was founded, whilst Watt appears to have supplied the conclusion.

Between the years 1783 and 1788, Cavendish published his papers on 'Heat,' and his 'Experiments on Air;' the former are three in number, and relate chiefly to the phenomena of congelation, and embody some of the results of experiments made as early as the year 1764. The first of these papers refer to quicksilver, demonstrating the true freezing-point of this metal to be 39° or 40° below zero, while the second and third refer to the freezing of the mineral acids and of alcohol.

His experiments on air, which led to the important results already referred to, supplied materials for four papers, besides leading to the observation of many phenomena which were never made public. With the last of these papers published in 1788, Cavendish closed his chemical researches, his remaining publications referring to meteorology and astronomy.

In 1798 appeared the celebrated enquiry into the density of the earth, communicated by Cavendish, in a paper to the Royal Society, in which he determined, by means of an apparatus contrived by the Rev. John Mitchell, the density of our globe to be 5·4,--or, in other words, nearly five-and-a half times heavier than the same bulk of water would be. The experiments made with this apparatus consisted in observing, with many precautions, the movements of a long lever delicately suspended by the centre, so as to hang horizontally, and furnished at either extremity with small leaden balls. When two much larger and heavier balls of the same metal were brought near the smaller ones, the latter were attracted towards them with a certain force, the measurement of which supplied one essential datum for the determination of the mean density of the earth. No greater compliment to the accuracy of the 'Cavendish Experiment' (as the researches taken as a whole are generally called) can be afforded, than the slight difference which appeared when the experiment was repeated at a later period by Francis Baily, who, with extraordinary precautions to ensure a correct result, and with all the improvements which forty fertile years had added to mechanical contrivances, determined the density to be 5·6, or a little more than five-and-a-half times that of water.

The last paper which Cavendish published, on an improvement in the manner of dividing astronomical instruments, appeared in 1809,--a year before his death. His published papers give, however, but an imperfect notion of the great extent of ground over which he travelled in the course of his investigations, and of the success with which he explored it. He was an excellent mathematician, electrician, astronomer, meteorologist, and geologist, and a chemist equally learned and original. He lived retired from the world among his books and instruments; he never meddled with the affairs of active life, but passed his whole time in storing his mind with the knowledge imparted by former inquirers, and in extending its bounds. His dress was of the oldest fashion; his walk was quick and uneasy; he never appeared in London unless lying back in the corner of his carriage; and he probably uttered fewer words in the course of his life than any man who ever lived to fourscore years. His private character has been thus described by Dr. George Wilson, from whose comprehensive life of Cavendish the present memoir has been chiefly taken:--

"Morally it was a blank, and can only be described by a series of negations. He did not love, he did not hate, he did not hope, he did not fear, he did not worship as others do. He separated himself from his fellow men, and apparently from God. There was nothing earnest, enthusiastic, heroic or chivalrous in his nature; and as little was there anything mean, grovelling or ignoble. He was almost passionless. An intellectual head thinking, a pair of wonderfully acute eyes observing, and a pair of very skilful hands experimenting or recording, are all that I recognize in his memorials. His brain seems to have been but a calculating engine; his eyes inlets of vision, not fountains of tears; his hands instruments of manipulation, which never trembled with emotion, or were clasped together in adoration, thanksgiving or despair; his heart only an anatomical organ necessary for the circulation of the blood. A sense of isolation from his brethren made him shrink from their society and avoid their presence; but he did so as one conscious of an infirmity, not boasting of an excellence. He was like a deaf mute, sitting apart from a circle whose looks and gestures show that they are uttering and listening to music and eloquence, in producing or welcoming which he can be no sharer. Wisely therefore he dwelt apart. He was one of the unthanked benefactors of his race, who was patiently teaching and serving mankind, whilst they were shrinking from his coldness or mocking his peculiarities. He could not sing for them a sweet song, or create a 'thing of beauty,' which would be 'a joy for ever,' or touch their hearts, or fire their spirits, or deepen their reverence or their fervour. He was not a poet, a priest, or a prophet, but only a cold clear intelligence, raying down pure white light, which brightened everything on which it fell, but warmed nothing--a star of at least the second, if not of the first magnitude in the intellectual firmament."

As Cavendish had lived, so he died--alone. He died after a short illness, probably the first as well as the last under which he ever suffered. His habit of curious observation continued to the end; he was desirous of marking the progress of disease and the gradual extinction of the vital powers. With this view, that he might not be disturbed, he desired to be left alone. His servant returning sooner than he had wished was ordered again to leave the chamber of death, and when he came back a second time he found his master had expired. Although in many respects of a highly liberal character, so great was the frugality of his ordinary mode of living in comparison to his income, that at his death Cavendish left the enormous sum of 1,200,000_l._ to be divided among his relations.--_Life of the Hon. Henry Cavendish, by George Wilson, M.D., F.R.S.E._ London, 1851.--_Brougham's Lives of Philosophers._ London and Glasgow, 1855.

WILLIAM CHAPMAN, M.R.I.A.

Born 1749. Died May 29, 1832.

William Chapman, Civil Engineer, was born at Whitby, in Yorkshire, of a respectable and wealthy family, who had resided in that town for several generations. He inherited the freedom of Newcastle-upon-Tyne from his father, who, in common with all the chief people of Whitby, was engaged in shipping, and was besides particularly distinguished for his attainments in mathematics and other scientific pursuits. William Chapman derived great advantage from his father's knowledge of these subjects, contracting a strong taste for similar occupations. After receiving a liberal education at different public schools, he was put in command, at the early age of eighteen, of a merchant vessel, in which he enjoyed the opportunity of visiting numerous harbours, both in Great Britain and other countries. He continued thus occupied for a period of three years, losing no opportunity of making himself acquainted with the circumstances of the various harbours he was in the habit of visiting, and he thus acquired that valuable practical knowledge on the subject of these works for which he became afterwards so highly distinguished.

After leaving the merchant service, Mr. Chapman was fortunate enough to become acquainted with James Watt, with his partner Matthew Boulton, and also with Mr. Wooller, Engineer to the Board of Ordnance. By these eminent men he was strongly advised to become an engineer, and follow as a profession that which he had already closely studied as an amusement. Chapman accordingly accompanied Mr. Boulton into Ireland, about the close of the year 1783, but although well introduced, was unable to obtain any employment of consequence in that country, until he had written a prize essay on the effects of the river Dodder on the Harbour of Dublin. Shortly after this, he was appointed resident engineer to the County of Kildare Canal, the works of which were carried on under the surveillance of the Duke of Leinster, the county members, and other leading men. In the execution of this undertaking, Mr. Chapman was requested not to alter the direction of the roads intersected by it, although one of them deviated from the right angle across the canal upwards of 50 deg. To meet this difficulty, and knowing that a bridge of the ordinary construction, with any obliquity, could not possibly stand, Chapman invented, and put into practice, the method of building oblique or skew bridges, which has since been so generally adopted throughout the country, in railway, canal, and other bridges. Before this period, (1787), whenever a road crossed the course of a canal or river, requiring the construction of a bridge, it had been usual to deviate the course, either of the road or the object it crossed, so that the crossing should be at right angles; a practice which occasioned a great waste of land and considerable expense as well as awkward and dangerous bends in the roads thus treated. In some few cases where the bridge was required to be of only a small opening, no alteration in the direction was made, but a bridge built of an oblique form, that is with abutments forming oblique angles with the road passing over it, the courses of the arch being built in lines parallel with the abutments, and the ends of the voussoirs bevelled off to coincide with the direction of the road. Bridges built in this manner consequently became highly dangerous when the span was great, or the obliquity considerable. The value of Chapman's invention consists in this, that he gave the means of building bridges on the skew principle, in any required situation, without altering the direction of the roads or wasting material, and at an expense little above that of ordinary rectangular bridges. This he accomplished by the principle of building the courses of voussoirs at right angles to the face of the arch, meeting the abutments at oblique angles, being the very reverse of the system previously practised.