HOUNSLOW, a district chapelry, and formerly a market-town, partly in the parish of Isleworth, but chiefly in that of Heston, union of Brentford, hundred of Isleworth, county of Middlesex, 9½ miles (W. S. W.) from London; containing 3097 inhabitants, of whom 1666 are in the Isleworth portion. This place, anciently called Hundeslawe, is situated on the principal road to the west of England, and consists chiefly of a long street, extending from east to west, irregularly paved, and lighted with gas; the inhabitants are well supplied with water. A priory of friars, of the order of the Holy Trinity, was founded here in the thirteenth century, the revenue of which, at the Dissolution, was £80. 15. 0¼. In 1296, a charter was granted to the prior for a market on Thursday, and an annual fair; the former has been long discontinued, but fairs are held on Trinity Monday and Tuesday, and the Monday following Michaelmas-day, for the sale of horses, cattle, &c. Adjoining the town, on the west, was formerly an extensive heath, the site of ancient encampments, and at different periods a military station, or place of rendezvous for troops, especially in the reigns of Charles I. and James II. On this heath are barracks for cavalry, which afford accommodation for 360 men with their horses. The heath has been inclosed, in pursuance of an act of parliament passed in the 53rd of George III., since which many buildings have been erected here. About two miles to the south-west of Hounslow are the extensive gunpowder-mills of Messrs. Curtis and Harvey, which have been very much improved within the last few years, and where a curious pump, worked by wind-sails, raises from thirty to fifty tons of water in a minute. Here are also another gunpowder-mill, and a mill for dressing flax. The living is a perpetual curacy; net income, £125; patron, the Bishop of London. The ancient chapel of the priory, which, after the Reformation, was used as a chapel of ease to Heston, was taken down, and the erection of a new church on its site was completed in Dec. 1829, at an expense of £5310, defrayed partly by the Parliamentary Commissioners, and partly by subscription; it is a fine edifice, in the later English style, with two turrets surmounted by dwarf spires. There are places of worship for Independents and Wesleyans.