GATE, in Engineering, is applied to the elose-boarded doors of locks or sluices on canals or rivers, for penning up the water : in a lock these are distinguished by upper-gates and lower-gates, according as they are placed at the head or tail of the lock.
GATE-Housu, a building erected over a gate, or that through which entrance was obtained into the main building. Gate-houses were very usual in the erections of the middle ages, and were employed in all large buildings, ecclesiastical, military, and civil, also as entrances to fortified cities; thus in London we still preserve the names of several gateways in the old wall, as New-gate, Bishops-gate, Lyd-gate, &c., at each of which places was formerly a gate-house, through which entrance was obtained within the city. These build ings were often of an imposing character ; and in military works consisted, for the most part, of a large arch-way with groined ceiling• and a portcullis at each end, flanked by two massive projecting towers, pierced with loop-holes, through which to annoy the enemy, and surmounted by a battle rnented parapet. Those attached to civil and ecclesiastical
buildings were generally of a more ornamental description, sometimes consisting of only a square tower with a turret at one or more angles, having a large arch-way in the centre with groined ceiling and room above, the window of which— frequently an oriel—formed a picturesque addition to the elevation. The forms of these gate-houses were, however, various, and admitted of different degrees of ornamentation. hI sonic cases, there was a small arch-way by the side of the principal one for foot•passengers, and in others a similar one on either side; they were called posterns. Remains still exist in most of the old towns, amongst the most remarkable of which are those of Rattle A blicy, Sussex, Bristol, Bury St. Edmund's, St. John's Gate, Clerkenwell, and St. Augus tine's College, Canterbury.