GREAVES (John)

, an eminent astronomer, antiquary and linguist, was born in 1602, being the eldest son of John Greaves rector of Colemore, near Alresford in Hampshire, and master of a grammar school, where his son of course was well grounded in the primary rules of literature. He then went to Baliol college in Oxford, in 1617; but afterward, on account of his skill in philosophy and polite literature, he was the first of five that were elected into Merton college. Having read over all the ancient Greek and Latin writers, he applied to the study of natural philosophy and mathematics; and having contracted an intimacy with Mr. Briggs, Savilian professor of geometry at Oxford, and Dr. Bainbridge, Savilian professor of astronomy there, he was animated by their examples to prosecute that study with the greatest industry; and not content with reading the writings of Purbach, Regiomontanus, Copernicus, Tycho Brahe, Kepler, and other celebrated astronomers of that and the preceding age, he made the ancient Greek, Arabian, and Persian authors familiar to him, having before gained an accurate skill in the oriental languages. These accomplishments procured him the professorship of geometry in Greshamcollege London, in 1630; and at the same time he held his fellowship of Merton-college.

In a journey to the Continent, in 1635, he visited the celebrated Golius, professor of Arabic at Leyden, and Claud Hardy at Paris, to converse about the Persian language. Hence he passed through Italy, and accurately surveyed the venerable remains of antiquity at Rome, visiting and corresponding everywhere with the most learned men of every nation. After visiting Padua, Florence, and Leghorn, he hence embarked for Constantinople, where he arrived in 1638. From thence he passed over to Rhodes, and Alexandria in Egypt, where he staid four or five months, and made a great number of curious observations. He next went to Grand Cairo, measured the pyramids; and while there he adjusted the measure of the foot, observed by all nations. From hence he returned again through Italy, and arrived in England in the year 1640, after storing his mind with a variety of curious knowledge, and collecting many valuable oriental manuscripts and ancient curiosities; and while at Rome he made a particular inquiry into the true state of the ancient weights and measures.

On the death of Dr. John Bainbridge, in 1643, he was chosen Savilian professor of astronomy at Oxford, and principal reader of Linacre's lecture in Merton college; an appointment for which he was eminently qualisied, from his critical acquaintance with the works of the ancient and modern astronomers. In 1645 he proposed a method of reforming the calendar, by omitting the intercalary day for 40 years to come: the paper relating to which, was published by Dr. Thomas Smith, in the Philos. Trans. for 1699. In 1646, he published his Pyramidographia, or a Description of the Pyramids of Egypt; and, in 1647, his Discourse on the Roman Foot and Denarius; from which, as from two principles, the measures and weights used by the Ancients may be deduced. He also published several other curious works concerning antiquities, &c.

Soon after publishing the last mentioned book, he was ejected, by the parliament visitors, from the professorship of astronomy and fellowship of Merton-college; and the soldiers committed many outrages, breaking open his chests, and destroying many of his manuscripts; which greatly affected him. On this occasion he retired to London, where he afterwards married, and prosecuted his studies with great vigour, as appears from several of his philosophical and theological writings. This however proved but a transient happiness to him; for he died at London, the 8th of October 1652, before he was quite 50 years of age; and left his astronomical instruments to the Savilian library in Oxford, where they are deposited.