REINS PILLAR.—Those affixed to the centrical pillars of a RIDING SCHOOL are so called; as are those likewise, by which the horse is kept confined ready for his rider, when saddled, bridled, and turned round in his stall. RELAY.—A relay of HORSES is a supply of fresh ones fixed at some particular spot, to exchange either upon a journey, or during the chase. A relay of HOUNDS more particularly applies to hunting excursions, where a part of the pack is alternately detached to a certain place of destination, that, by a relay of both HORSES and HOUNDS, the sport may be continued daily, without intermission, during the week. REPOSITORIES—are placed in the metropolis, where horses are received for PUBLIC or PRIVATE sale, and where they are regularly _bought_ and _sold_ by AUCTION, on certain days in every week. This is an accommodation of so much convenience and utility to those who have occasion either to BUY or to SELL suddenly, that the succession of horses is incessant, and the PROPRIETORS never feel a want of public patronage. The three long-established repositories are TATTERSAL'S, near HYDE PARK CORNER; ALDRIDGE'S, in ST. MARTIN'S LANE; and LANGHORN'S, (called the City Repository,) in BARBICAN. The days of sale at the first are MONDAYS and THURSDAYS; at the second, on WEDNESDAYS; and at the latter, on FRIDAYS. TATTERSAL'S is the principal receptacle for horses in high estimation, as running horses, stallions, brood mares, hunters, and the superior kind of hacknies. CARRIAGES and HARNESS may be deposited here for sale by auction, or private contract; as may also HOUNDS, POINTERS, SPANIELS, GREYHOUNDS, or any sporting stock whatever. ALDRIDGE'S was the original as a repository, and the first institution of the kind in the kingdom. It was opened upon speculation by a MR. BEAVER, in which he acquired fame and fortune. This is principally appropriated to the sale of hunters, light carriage horses, famous trotters, sporting-like hacknies, and others of every description; from which universality of accommodation (notwithstanding the great extent of the premises) there is but very seldom a single stall to spare. The sales at LANGHORN'S principally consist of stage-coach, waggon and cart horses, hacks, and occasionally government horses of the dismounted cavalry.