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amount of £1,300,000. Regarded as a man, his character presents little to be admired. With all his immense wealth, he does not appear to have encouraged learning and science in any other way than by keeping a valuable library, open to the use of literary men. To these he confined his society, but even in the circles of his most intimate friends, he was occasionally shy and silent.

Of parade and compliment he had an absolute horror; a singular instance of which is related to have occurred at one of the Sunday meetings at Sir Joseph Banks's. Dr. Ingenhouz came up to him, in a pompous manner, with an Austrian gentleman in his hand, whom he formally introduced to him by all his titles. The gentleman then began a speech, in which he assured Mr. Cavendish that his principal reason for visiting London, was his ardent desire to see and converse with one of the ornaments of the age, and the most illustrious of philosophers. Mr. Cavendish stood with his eyes cast down, not answering a word, and betraying every sign of distress and confusion. At length, spying an opening in the circle, he darted through it, and, with all speed, escaped to his carriage, and drove directly home.

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He scarcely maintained any communication with his family, and is said only to have seen once a-year, and that for a few minutes, the relative to whom he left the bulk of his property. fore the discoveries of Priestley, Scheele, and Lavoisier, the experiments of Mr. Cavendish had opened a path of chemical investigation equally new and splendid. As a mathematician he has been excelled by many of his predecessors; but none of them, it is to be observed, had attempted to employ their powers of investigation in the pursuit of physical discovery. "Whatever the sciences revealed to Mr. Cavendish," says Cuvier, "appeared always to exhibit something of the sublime and the marvellous; he weighed the earth; he rendered the air navigable; he deprived water of the quality of an element; and he denied to fire the character of a substance. The clearness of the evidence on which he established his discoveries, new and unexpected as they were, is still more astonishing than the facts themselves which he detected; and the works in which he has made them public, are so many masterpieces of sagacity and methodical reasoning, each perfect as a whole and in its parts, and leaving nothing for any other hand to correct.'

NEVIL MASKLELYNE.

NEVIL, son of Edmund Masklelyne, of Preston, in Wiltshire, was born in London, in October, 1732, and educated at Westminster School and the University of Cambridge. Optics and astronomy attracted his attention at an early age; and, in order to a full comprehension of these sciences, he applied himself with ardour to mathematics; and, in a few months, made himself master of the elements of geometry. After taking his bachelor's degree at the university, where he was first a member of Catherine Hall, and afterwards of Trinity College, he obtained a curacy in the neighbourhood of London, whither he removed in 1755. Here he became acquainted with Dr. Bradley, and pursued his favourite studies with such suc

cess, that his name soon became known to the scientific world. In 1758, he was elected a fellow of Trinity College, Cambridge; of the Royal Society of London, in 1759; and, in the autumn of the following year, was appointed by that body to visit the island of St. Helena, in order to observe the transit of Venus over the sun, which was to happen on the 6th of June, 1761.

On his return, he published, in 1763, a useful practical work, called The British Mariner's Guide; and, in the same year, being appointed chaplain to his majesty's ship, the Louisa, he went out to Barbadoes, by order of the board of longitude, in order to ascertain the correctness of Mr. Harrison's timekeeper. In 1765, he was appointed

astronomer-royal; and, soon afterwards, placed before the board of longitude a plan for An Annual Nautical Almanack and Astronomical Ephemeris, The former was published in 1767; and, in the same year, appeared, by order of the board of longitude, his Account of the going of Mr. John Harrison's Watch, &c., which gave rise to a controversy between him and the inventor. In 1774, were published his Tables for Computing the Apparent Places of the Fixed Stars, and Reducing Observations of the Planets. They were followed, about two years after, by the first volume, in folio, of Astronomical Observations made at the Royal Observatory, Greenwich, which were continued annually till 1803,

During the years 1774, 1775, and 1776, Mr. Masklelyne was engaged in endeavouring to determine the mean density of the earth. An unsatisfactory experiment had been previously made by Bouguer, who, in attempting to determine the attraction of mountains from the quantity by which the plumbline of the astronomical sector was affected, found only half the quantity it should have been from the size of the mountain, which he, therefore, concluded to be hollow. The subject of our memoir chose, for the place of his observation, the mountain of Schehallien, in Scotland, taking with him the sector he had used at St. Helena, after having corrected the suspension and changed the divisions. The result was such as to tend to the presumption that the internal parts of the earth contain large quantities of metals, the mean density of the earth to that of water

being calculated as nine to two, and to that of stone as nine to five.

In 1792, Dr. Masklelyne published M. Michaelis Taylor's Tables of Logarithms, to which he prefixed a very masterly introduction, containing precepts for the use of them. His communications to the Transactions of the Royal Society, which are valuable and numerous, are to be found in the volumes from the fifty-first to the seventysixth. He published, separately, few works of importance besides those already mentioned, if we except his edition of Mayer's Tables and Precepts, and his Observations on the Equation of Time, in which he has pointed out an error of La Caille and Laplace. He is said to have been the inventor of the prismatic micrometer; the idea, at all events, of employing a double refraction, is undoubtedly his. It does not appear in what year he received his doctor's degrees, but it was some time previous to 1782, in which year he was presented to the living of North Runeton, Norfolk. He died. highly respected for his amiable and pious character, in 1811, leaving one daughter.

His merits, as an astronomer, have been summed up by Delambre, who justly observes, that Masklelyne left the most complete set of observations with which the world was ever presented; "and if, by any great revolution," he adds, "the works of all other astronomers should be lost, and this collection preserved, it would contain sufficient materials to raise again, nearly entire, the edifice of modern astronomy.”

SIR RICHARD ARKWRIGHT.

RICHARD ARKWRIGHT was born of humble parents, in Preston, Lancashire, in 1732. His original occupation was a barber, and he practised that calling when he first came to Warrington, the scene of the commencement of his mechanical career, in 1767. He had, at this time, invented a contrivance of something in the nature of perpetual mution, but a watchmaker, of the name

of Kay, to whom he showed it, dissuaded him from continuing his operations. The same person, who appears to have failed in a similar attempt, remarked to Arkwright, that he might, with profit, turn his attention to cotton-spinning, and offered to describe to him the process. Arkwright, after some objections to the scheme, in consequence of its having already ruined so many, undertook

to embark in it, and, in conjunction with Kay, applied to Paul Atherton, Esq., of Liverpool, to construct an engine. This the poverty of our inventor's appearance induced the gentleman at first to refuse; but he afterwards consented, on the understanding that Kay should make the clockmaker's part of the engine, and superintend the progress of the work, in its general construction. Soon after its completion, Mr. Arkwright took out a patent for his engine, in 1769, and renewed it in 1775; but, in consequence of the above facts having been brought before the King's Bench, it was, by that court, set aside, in 1785.

Not long after he had obtained his patent, Arkwright had entered into partnership with a Mr. Smalley of Preston, but failing for want of money, they removed to Nottingham, where the assistance of some rich capitalists enabled them to erect a considerable cotton-mill, turned by horses. On the secession of Smalley, Mr. Dale, a Scotchman, was taken into partnership by Arkwright, who, as he was attacked, about this time, by other English manufacturers, used to say, that he would put into the hands of a Scotchman a razor that would shave them all.

Arkwright was knighted in December, 1786, on presenting an address from the high sheriff and hundred of Wirksworth. At this time, he resided at his works at Crumford, in Derbyshire, where, being able to make his engines go by horses, by water, and by steam, as first movers, he was rapidly amassing a large fortune. He died there on the 3rd of August, 1792, leaving behind him, it is said, property to the amount of £500,000.

Sir Richard Arkwright's invention cannot be considered as altogether new, nor is he entitled to the exclusive merit of its construction, as we have seen that Kay, the watchmaker, had a great share in it, and, indeed, suggested to Sir Richard the scheme. The crudity of the idea, however, was matured by Arkwright, and great credit is due to him for the perseverance which he used in bringing it into practical operation. He trod a path where several had previously failed, as he himself tells us, in a statement of his own case, wherein he states that, among others, one Hargrave, of Blackwell, in Lancashire, after having obtained a patent, in 1767, for an engine that would at once spin twenty or thirty threads of cotton into yarn for the fustian manufacture, had his machines destroyed by popular tumult, and was, at length, by private combination, deprived of his patent, and died in obscurity and distress. Arkwright had also to contend against many disadvantages, and he was not able to accomplish his object with any profit to himself or his partners, until a period of five years, and a sum of £120,000 had been consumed. whatever may be his merit as an original inventor, this country is certainly indebted to him for having raised the carding and cotton-spinning, from comparatively nothing, to a great national manufacture. Some idea of the influence which his invention has had upon the increase of cotton fabrics may be formed, from the fact that the annual importation of raw cotton from 1771 to 1780 averaged only 5,735,000 lbs; whilst from 1817 to 1821, it amounted to 144,000,000, of which 130,000,000 lbs. were spun in England.

But

JOSEPH PRIESTLEY.

THIS eminent philosopher was born at Fieldhead, near Leeds, in Yorkshire, in March, 1733. His father was engaged in the clothing manufacture, and was a Calvinistic dissenter; but the care of his education devolved on an aunt (Mrs. Keighly), by whom he was adopted almost from his infancy. She

was a woman of exemplary benevolence and piety, and was neither unremitting nor unsuccessful in her endeavours to instil the same qualities into her nephew. He received the first part of his education at several schools in the neighbourhood of Leeds, where he made considerable progress in the learned

languages, including Hebrew, with a view of fitting himself for the ministry. His weak health threatened, for a time, to frustrate this intention, and he, in consequence, applied himself to the modern languages, in order to qualify himself for a merchant in Lisbon. His constitution, however, becoming renovated, he resumed his original purpose; and, in 1752, went to complete his course of theological studies at the dissenting academy, kept by Dr. Ashworth, at Daventry. On his entrance into this establishment, he was found to possess a considerably greater degree of knowledge than might have been expected from his years, even with the studious habits by which they were accompanied, whilst his conduct was marked by a strict sense of religion, and displayed that vital spirit of piety, which even, in some degree, assimilated him to that class of Christians, from whose doctrines no one more widely deviated.

He remained at Daventry three years, pursuing, during that time, such a course of theological inquiry, as at length induced him to relinquish the orthodox system in which he had been educated, for that of Arianism. It was here, also, that he first read the works of Dr. Hartley, to whose theories he soon became a convert, and whose writings ever afterwards maintained a powerful influence over his whole train of thinking. On leaving Daventry, he accepted the charge of a small congregation at Needham Market, in Suffolk; but neither his style of preaching, nor the opinions which he held, were of a nature to render him a popular minister in this place. It is even said that the dissenting clergymen in the neighbourhood considered it a degradation to associate with him; and were afraid to ask him to preach, because the genteeler part of their audience always absented themselves when he appeared in the pulpit. Yet, many years afterwards, as he informs us himself, when his reputation was very high, and he preached in the same place, multitudes flocked to hear the very same sermons which they had formerly listened to with contempt and dislike. He passed, therefore, the three years of his pastorship at Needham in poverty, discountenance, and obscurity; "but still pursuing his theological and scriptural

researches with equal ardour and boldness. The consequence was, before he left Needham, a still further departure from the received systems, and, in particular, his total rejection of the doctrine of atonement.

In 1758, he appeared as a candidate for a meeting-house in Sheffield, but his trial-sermon was not approved of. In the following year, he removed to Namptwich, in Cheshire, where he officiated as minister, and also opened a school, in which he taught with indefatigable zeal. To the common objects of instruction, he added that of natural philosophy, and thus fostered in himself a taste for the pursuit of that science. In 1761, he published, for the use of his scholars, an English Grammar, on a new plan; and, in the same year, he was invited by the trustees of the Dissenting Academy at Warring ton, to fill the post of tutor in the languages. He, soon after, married the daughter of a Mr. Wilkinson, an iron master near Wrexham, a lady who is said to have been of very good understanding, and great strength of mind.

His reputation, as a man of various knowledge and active inquiry, now began to extend itself, and he was not long in supporting his claim to it by his writings in various branches of literature and science. Of these, many related to his department in the academy, which included, besides philology, lectures on history and general policy. His ideas of government, of which we shall speak hereafter, were supported by him in An Essay on Government, which was followed by An Essay on Education, with some remarks in animadversion of a treatise on the same subject by Dr. Brown, of Newcastle. About the same time also appeared his Chart of Biography, an ingenious and highly commended work. He shortly after visited London; and, during his stay there, contracted an acquaintance with Dr. Franklin, Dr. Watson, Dr. Price, and Mr. Canton, by whom he was encouraged to pursue a plan he had formed of writing A History of Electricity. This work, which he published in 1767, relates to many new and ingeniously devised experiments of his own, besides containing a very clear and well arranged account of the rise and progress of electricity. It was re

ceived with great applause, both abroad and at home; was translated into foreign languages, and went through several editions. The Royal Society immediately admitted the author a member of their body; and, about the same time, the University of Edinburgh conferred upon him the degree of LL.D. In 1767, he quitted the academy at Warrington to become minister to a large congregation of dissenters at Leeds. This he found a very agreeable change; the liberality of his opinions met with no check from those over whom he presided; and pursuing his theological inquiries with renewed ardour, he became a convert to Socinianism. This change he attributed to a perusal of Dr. Lardner's letter on the Logos; and he evinced his sincerity and zeal by a number of publications on the subject. The labours of the closet did not hinder him from discharging his more active duties as a pastor; on the contrary, his personal efforts to instruct his flock were most assiduous, and, in particular, with regard to the younger portion.

sciences, which, had he known them
earlier, might, probably, have induced
him to follow some beaten track. To
his little knowledge of chemistry, at
this time, he himself ascribes the ori-
ginality of his experiments, and the
subsequent discoveries to which they
gave rise one experiment led to ano-
ther, till he, at length, arrived at that
reputation which has insured immor-
tality to his name; but of which he
himself spoke with a modesty not often
to be met with among the most humble
favourites of fame.
"Few persons, I
believe," he says, in his autobiography,
"have met with so much unexpected
good success as myself, in the course of
my philosophical pursuits. My nar-
rative will shew that the first hints, at
least, of almost everything that I have
discovered of much importance, have
occurred to me in this way; in looking
for one thing, I have generally found
another, and sometimes a thing of much
more value than that which I was in
quest of. But none of these expected
discoveries appear to me to have been
so extraordinary as that I am about to
relate, viz. the spontaneous emission of
dephlogisticated air from water con-
taining green vegetating matter; and it
may serve to admonish all persons who
are engaged in similar pursuits, not to
overlook any circumstance relating to
an experiment, but to keep their eyes
open to every new appearance, and to
give due attention to it, however incon-
siderable it may seem.'

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But whilst he was thus rising into eminence among the dissenters, he was also following up those ideas and investigations, which ended in some of the most magnificent discoveries that have enlightened the world of science. A brewery at Leeds, which happened to adjoin his residence, first called his attention to the properties of that gaseous fluid then termed fixed air; respecting which he made a number of experiments, and at length succeeded in contriving a simple apparatus for impregnating water with it. He published an account of this in 1772; and, in the same year, encouraged by the success which his History of Electricity had met with, he published, by subscription, in one volume, quarto, The History and Present State of Discoveries relating to Vision, Light, and Colours. The performance, though one of great merit, fell short of the general expectations; and, fortunately for science, was received with a comparative cold-previously known, and he had been in ness, which induced the author to confine himself to original researches of the experimental kind. For this he was eminently fitted; his inquiring and original turn of mind being impelled by all the ardour of genius, unshackled by too strict an acquaintance with those

Dr. Priestley appears to have commenced his experiments, with regard to fixed air, as early as 1768, and it was before the former year that he procured good air from saltpetre; discovered the uses of agitation and of vegetation as means employed by nature in purifying the atmosphere, destined to the support of animal life; and that air, vitiated by animal respiration, is a pabulum to vegetable life. Factitious air bad also been procured by him in a much more extensive variety of ways than had been

the habit of using mercury, instead of water, for the purpose of many of his experiments. Of these discoveries, he gave an account in a paper read before the Royal Society, in 1772, together with an announcement of the discovery of nitrous air, and its application as a test

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