market-town of England, county of Suffolk, on the Bret, a tributary of the Stour, 9 miles W.S.W. of Ipswich. It was formerly a corporate town, and a place of considerable trade, but it has lost its charter; and its trade, which was chiefly in cloth, has declined. Silk-spinning is carried on to some extent, but the inhabitants are chiefly employed in agriculture. The church is a large and handsome building, with a tower and spire. Dr Rowland Taylor, rector of Hadleigh, was burned here in the reign of Queen Mary, the spot being marked by a stone with this inscription, "—1555. Dr Taylor, in defending that was good, at this pass left his blode." Market-day, Monday. Pop. (1851) 3338.

Hadley, John (——1744), a distinguished English astronomer, of the details of whose life almost nothing is known. He was a member and afterwards a vice-president of the Royal Society, to whose Transactions he made some valuable contributions. He was the inventor of the sextant which bears his name, or at least the first who made it practically useful at sea; for the idea had been long before struck out by Hooke and perfected by Newton. Some important changes and improvements have since been made upon it by Mayer and Borda.

Hadrianopolis, in Ancient Geography, the name of several cities founded by the Emperor Hadrian, by whose name they were called. The largest and most important of these was that in Thrace, at the confluence of the Hebrus and Tonzus, which seems to have occupied the site of the more ancient city of Uscudama. It stood in the midst of a country of remarkable fertility, and its commerce and manufactures soon raised it to great importance. Its arms were noted over the East. It was besieged by the Goths in 378, but it soon recovered the shock, and was for many centuries the largest city in the Eastern Empire after the capital. (For its modern history, see Adrianople.) There were three other minor towns of this name, one in Bithynia, another in Phrygia, and a third in Illyricum, half-way between Nicopolis and Apollonia. The name of the last was changed into Justinopolis by the Emperor Justinian, who fortified and repaired it.