Ferguson next went.into the service of a miller, expect ing to have sufficient time to study decimal arithmetic and geometry. His master, however, fond of drinking, left him the whole charge of the mill, and almost starved him for want of food. As soon as he had recovered the strength which he had lost by the poverty of his diet, he went into the service of a Dr Young, who acted in the joint capa city of a farmer and a physician, and who promised to in struct him in the medical profession. This new master, however, was as bad as the former one. He never even slimed him one of his books, and overwrought him to such a degree, that at the end of three months he was obliged to leave him in a state of great debility, and with out receiving a farthing of wages. This inhuman doctor did not even give him any medical advice, and it was only by medicines from his old friend Cantley, who lived at 12 miles distance, that he recovered his strength. About that time he constructed a wooden clock, the frame of which was of wood, the hours being struck on the neck of a broken bottle instead of a bell. Some time afterwards, when a gentleman was riding past his father's 'house, he asked him what o'clock it was ; and having received a very good-natured answer, he begged of him to chew him the inside of his watch, as he could not conceive how it went without a weight and a string. The gentleman kindly complied with this request, and not only shewed him the inside of his watch, but explained to him very clearly in what manner the box was carried round by the uncoiling of the spring. Ferguson then tried to construct a watch with wooden wheels, and a whalebone spring; but upon putting on the balance, he found that the teeth of the wheels were too weak to bear the force of the spring, al though the wheels ran fast enough when the balance was taken off. He inclosed the whole in a wooden case, a lit tle larger than a breakfast cup; but a clumsy neighbour one day looking at the watch, allowed it to fall, and crush ed it to pieces with his foot. Ferguson was next employ ed in cleaning and repairing clocks ; and when he was liv ing at th mouse of Sir James Dunbar of D urn, he painted a map ofMie celestial and terrestrial globe, upon two large spherical stones on the top of his gateway. These globes had their axes parallel to that of the earth, and not only served for dials, but exhibited a number of interesting geographical phenomena. Having drawn some patterns for needlework for Lady Dipple, (sister of Sir James Dun bar), he was very extensively employed in this work by the ladies in the vicinity, and he received so much money from his new employment, that he was often able to re lieve the wants of his indigent father. Lady Dipple had the goodness to invite him to Edinburgh, and offered him a year's bed and board at her house, that lie might have an opportunity of acquiring a knowledge of painting. He drew portraits of several persons in Edinburgh ; and, by the patronage of the Marchioness of Douglas, he obtained a considerable deal of lucrative employment, and thus be gan a profession which he followed for 26 years. During his stay of two years in Edinburgh, he took a violent incli nation to study medicine, and he forsook for a time all his favourite studies. He then went to the country with a cargo of medicines and plasters, hut with a very scanty knowledge of the art, and began to practise medicine at the place of his nativity. He soon saw, however, that he was an unsuccessful practitioner ; and finding that no one paid him for his medicines, he went to Inverness for the purpose of resuming his profession as a painter. During his stay at Inverness, he recommenced his astronomical studies, and after much labour, he invented and completed a machine called the .1stronomical Ronda, for exhibiting the eclipses of the sun and moon. Mr Macbean, one of the ministers of Inverness, compared the results given by this machine with the calculations given in the common almanac, and found them nearly the same. At his advice, he wrote to the celebrated Cohn M'Laurin, Professor of Mathematics in Edinburgh, and requested his opinion of the new instrument. M'Latirin returned him a friendly answer, and requested from him a drawing of his rotula, that he might examine it, and endeavour to procure a sub scription for the purpose of getting it engraved upon cop perplates. Mr Ferguson immediately complied with this kind request, and a handsome subscription was obtained through the influence of the Professor. The plates of the rotula were engraved and published, and went through several impressions, till the year 1753, when they were rendered useless by the change of style. When he went to Edinburgh, he was received with the greatest kindness by IVFLaurin, who shelved him his orrery, but was not able to let him see its construction. Ferguson immediately set to work, and constructed an orrery of wood, which exhi bited almost all the leading phenomena in astronomy. N'Laurin was so much pleased with this machine, that he desired Ferguson to read a lecture upon it before the ma thematical class. He soon afterwards, in 1743, made a smaller and a neater orrery, having all the wheels of ivory, and he took it with him to London, where it was bought by Sir Dudley Rider.
When he reached London, he began his old profession of portrait painting, amusing himself at his leisure hours with his astronomical studies. He now constructed a sim ple machine for delineating the moon's path and that of the earth, on a long piece of paper laid on the floor. This ma chine was shewn to Martin Folkes, President of the Royal Society, who took Mr Ferguson to the meeting of the So ciety that evening, when he skewed his instrument, and explained the use of it. When the Society was dismissed,
one of the members, Mr John Ellicott, a celebrated watch maker, asked Ferguson to dine with him at Hackney, and upon that occasion he slimed him that he had invent ed and constructed the very same machine many years be fore.
In 1747, Mr Ferguson published a dissertation on the phenomena of the harvest moon, with the description of a new orrery with only four wheels. In 1748, he read lec tures on the eclipse of the sun that happened on the 14th of July of that year. He afterwards read astronomical lectures on an orrery which he constructed, and which he has represented in the 6th and 7th Plates of his Mechani cal Exercises. He then began to construct an apparatus for lectures on mechanics and other branches of experi mental philosophy. These lectures were repeated in va rious parts of the kingdom, and added both to the fame and wealth of our author. In the year 1754. Ferguson publish ed " A brief Description of the Solar System, to which is subjoined an Astronomical Account of the year of our Sa viour's Crucifixion, and likewise an Idea of the Material Universe, deduced from a Survey of the Solar System." In 1756, he published in one vol. quarto, one of his best works, entitled "Astronomy explained upon Sir Isaac Newton's Principles, and made easy to those Who have not studied Mathematics." This work was written with such uncommon perspicuity and plainness, that it was translated into the German and Swedish languages, and has undergone no fewer than thirteen or fourteen edi tions. A new edition of it has lately been published by Dr Brewster, in 2 vols. 8 VO, containing an account of all the new discoveries in the science since the time of Fer guson.
About this time Mr Ferguson was introduced to Iris present Majesty, then Prince of Wales, who attended his lectures, and took great pleasure in conversing with him on astronomical subjects. Mr Ferguson received several presents from the prince, and when he ascended the throne, he allowed him 50/. a year out of his privy purse, which was regularly paid to hint without any deduction.
In 1760, Ferguson published his " Lectures on Select Subjects in Mechanics, Hydrostatics, Hydraulics, Pneu matics, Optics, Geography, Astronomy, and Dialling," Eke. This work, which is perhaps the best and the most useful that he ever wrote, passed through several edi tions, and contributed more to the diffusion of mechanical knowledge among all classes of people, than all the works that have been written upon these subjects. A new edi tion of it in 2 vols. 8vo, with an Appendix, containing an account of all the recent inventions and discoveries, was published by Dr Brewster in 1805, and a second edition in 1806.
In 1761, he published his " Plain Method of determin ing the Parallax of Venus by her Transit over the Sun, and thence, by analogy, the Parallax and Distance of the Sun, and of all the rest of the Planets." In 1763, he was elected a Fellow of the Royal Society of London, and was excused the payment of the usual fees, which had only been done in the case of Sir Isaac Newton, and of that ingenious and self-taught mathematician Mr Thomas Simson of Woolwich. In the same year he published his " Astronomical Tables and Precepts for calculating the true Times of New and Full Moons, and shewing the Method of Projecting Eclipses from the creation of the World to A. D. 1800, to which is prefixed a short Theory of the Solar and Lunar Motions." In 1767 he published " Tables and Tracts relative to several Arts and Sciences," and also " A Supplement to the Lectures, on Mecha nics, Hydrostatics, &c." which is annexed to all the sub sequent editions of that work. His "Young Gentleman's and Lady's Astronomy familiarly explained, in ten Dia logues," appeared in 176S, and was reprinted in 1769, under the title of, "An easy Introduction to Astronomy, for Young Gentlemen and Ladies." This little work has gone through eight editions, and was translated into German in 1771. Midame Geniis remarks, in her preface to the " Tales of the Castle," that this work is so perspicuous, that a child ten years old may completely understand the whole of it. In the year 1770, he was chosen a member of the Ameri can Philosophical Society; and, in the same year, he pub lished his " Introduction to Electricity." His "Select Mechanical Exercises, shewing how to construct different Clocks, Orreries, and Sun-Dials, on plain and easy princi ples," &c. appeared in 1773, and were accompanied with an account of his life, written by himself. In 1775, he published "Two Letters to the Rev. John Kennedy, corn taining an account of many mistakes in the astronomical part of his scriptural chronology, and his abusive treatment of astronomical authors." These were followed by a third letter on the same subject. In the same year he pub lished his last work, entitled " The Art of Drawing in Perspective, made easy to those who have no Knowledge of the Mathematics." This work has gone through seve ral editions, and was translated into French by P. R. Le veque. Besides these works, Mr Ferguson communicated several papers to the Royal Society, which were printed in the Transactions of that learned body; but as the most im portant of them were reprinted in his own works, it is un necessary to give any enumeration of them at present. Mr Ferguson had always a weak constitution ; and, after strug gling against a lingering illness, he died on the 16th of November, in 1776, in the 66th year of his age, leaving behind him an only son, who is still alive, and to whom he bequeathed a very considerable sum of money, which he had made by his lectures and his various works. (7r)