Besides the miscellaneous poets, the dramatic ones numbered Congreve, Vanbrugh, Farquhar, Colley Cibber, Nicholas Rowe—already mentioned—Savage, Lansdowne, Ambrose Philips, and others. In many of the plays of these authors there is great talent, wit, and humour, but mingled with equal grossness. Congreve's dramas are principally "The Old Bachelor," "The Incognita," "The Double Dealer," "The Way of the World," comedies, and "The Mourning Bride," a tragedy. Vanbrugh, the celebrated architect, produced "The Relapse," "The Provoked Wife," "The Confederacy," "The Journey to London," and several other comedies. Farquhar's principal plays are "The Beaux's Stratagem," "Love and a Bottle," and "The Constant Couple." Savage was the author of the tragedy of "Sir Thomas Overbury;" Nicholas Rowe, of five or six tragedies and one comedy, the most popular of which are "The Fair Penitent" and "Jane Shore." Rowe also translated Lucan's "Pharsalia." As for Colley Cibber, he was a mere playwright, and turned out above two dozen comedies, tragedies, and other dramatic pieces. Lord Lansdowne was the author of "The She-gallants," a comedy, and "Heroic Love," a tragedy of some merit; and John Hughes wrote "The Siege of Damascus," a tragedy, which long remained on the stage.

James Bradley (b. 1692), who succeeded Halley as the third Astronomer Royal, held that post till 1762, when he died. He had in 1728 distinguished himself by his discovery of an unanswerable proof of the motion of the earth by his observations on the apparent alteration in the place of a fixed star. His second great discovery was that of the mutation of the earth's axis, showing that the pole of the equator moves round the pole of the elliptic, not in a straight but in a waving line. Bradley gave important assistance to the Ministry in their alteration of the calendar in 1751, and the vast mass of his observations was published after his death, by the University of Oxford, in two volumes, in 1798.

COSTUMES OF THE PERIOD OF GEORGE II.

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Halley's quadrant was constructed and made known by him to the Philosophical Society, in 1731, though Thomas Godfrey, a glazier, of Philadelphia, is said to have made a similar instrument a year before. As early, however, as 1727 Newton had described such an instrument to Halley, that is, a very little time before his death. This invaluable instrument has since been improved, first into a sextant, and ultimately into a complete circle. In 1758 appeared John Dollond's corrections of Newton's views of the dispersion of refracted light, and in the following year his achromatic telescope, based on his accurate discoveries.

In 1720 Colin Maclaurin, the successor of James Gregory in the mathematical chair at Edinburgh, published his "Geometrical Organica," a treatise on curves; in 1742 his admirable treatise on Fluxions; and in 1748 his treatise on Algebra. Dr. Robert Simson, professor of mathematics at Glasgow, published a restoration of the "Loci" of Apollonius, and an English translation of Euclid, which continued down to a late period in use, both in Scotland and England. In 1717 James Stirling published a Latin treatise on lines of the third order, and another on Fluxions, called "Methodus Differentialis," in 1730. William Emerson, a mathematician and mechanist, wrote on fluxions, trigonometry, mechanics, navigation, algebra, optics, astronomy, geography, dialling, etc., but a considerable portion was only in part published during this period. Thomas Simpson, a weaver, of Market Bosworth, at the age of seven-and-twenty suddenly discovered himself as an extraordinary mathematician, and went on till his death, in 1761, publishing works on fluxions, the nature and laws of chance, on mixed mathematics, on the doctrine of annuities and reversions, on algebra, elementary geometry, trigonometry, etc. James Ferguson, also, the son of a day-labourer, in Banffshire, studied mathematics whilst tending sheep, and published a number of works on the phenomena of the harvest moon, astronomy, mechanics, hydrostatics, pneumatics, and optics. Ferguson had a remarkably lucid and demonstrative style, both in writing and lecturing, and his example excited a keen spirit of inquiry amongst the working classes, so that he is said to have diffused the knowledge of physical science amongst the class from which he sprang more than any other man.

In electricity great strides were made. Between the years 1705 and 1711 Francis Hawksbee published in the Transactions of the Royal Society several experiments, in which he had, for the first time, discovered the production of the electric spark by friction, and electrical attraction and repulsion. In 1720 Stephen Gray, a pensioner of the Charterhouse, published the result of his experiments on this subject, with a list of the substances which showed electricity under friction; and in 1732 he discovered the conducting property of non-electrical bodies. Before 1739, Dufray, keeper of the King's Garden at Paris, discovered the repellent power of two similarly-electrified bodies, and the attraction of these positively and negatively electrified—or, as he termed it, possessing the vitreous and the resinous electricity. Cuneus and Lallemand discovered the mode of accumulating the electric fluid in what was called the Leyden jar in 1745. This discovery gave a new impetus to inquiry, and Nollet, in France, and Watson, in England, conceived the hypothesis of the jar being overcharged on one side and undercharged on the other. This growing perception of the positive and negative conditions of the electric fluid received confirmation from the experiments of Benjamin Franklin, in America. Franklin soon improved the Leyden jar into an electrical battery; and, in 1752, he proved the identity of electricity and lightning by his grand experiment of the kite. On this he recommended lightning conductors, which, however, were not used in England till ten years afterwards.

On the laws of heat and cold, and atmospheric changes under their influence, many interesting facts were ascertained by the aid of the thermometers of Fahrenheit and Réaumur. Dr. Martin, of St. Andrews, distinguished himself in these inquiries, and published his discoveries and deductions in 1739 and 1740. In 1750 Dr. Cullen drew attention to some curious facts connected with the production of cold by evaporation. Dr. Joseph Black discovered what he called latent heat, and continued his researches on this subject beyond the present period.

Chemistry also received valuable extensions of its field. Dr. John Mayow published new facts respecting nitre, and on the phenomena of respiration and combustion, as revealed by experiments on this and other substances. At the commencement of the eighteenth century Stahl, a German chemist, propounded his theory of phlogiston as the principle of combustion, which was only exploded by the further discoveries of Dr. Black, Cavendish, and Priestley. Soon after, Dr. Hales threw new light on aëriform bodies, or, as they are now termed, gases; and finally, Dr. Black demonstrated the presence of a gas in magnesia, lime, and the alkalies, which had long before been noticed by Van Helmont, but had been forgotten. This was then termed fixed air, but has now acquired the name of carbonic acid gas, or carbon dioxide. At the end of this period chemistry was extensively studied, and was rapidly revealing its secrets.