SKYLIGHT. Including under this term every mode of admitting light into an apart ment through its roof or ceiling, we may here briefly notice that particular fashion of sky light distinguished in gothic architecture by the name of Lantern, though lanterns in gothic buildings were not so much intended to admit light as to supply ventilation and the means of escape to smoke. But the term lantern is also applied to the lower part of a tower placed at the intersection of the tran septs with the body of a church, which, being open below, forms a loftier portion of the interior, lighted by windows on each side ; and again to an upper open story, that is, one entirely filled with on the summit of a tower, and frequently forming a superstruc ture different in plan from the rest, as in Fotheringay Church, and that at Boston, Lin: colnshire, in both which examples the lantern forms an octagon placed upon a square. The upper portion of the tower of St. Dunstan's, Fleet Street, London, may also be described as a lantern.
Of skylights, however, properly so called (that is, which are nearly in the same plane as the general sin-face of the ceiling), no ex amples are to be met with in our ancient architecture ; nor does anything of the kind occur in Italian architecture, except it be in the form of a cupola over a central saloon. An example of a church lighted entirely from above, without lateral windows, is furnished by that of St. Peter-le-Poor, Broad Street, London, which is a rotunda, covered by a cove, and a large circular lantern, whose tambour forms a sort of clerestory, consisting of a continuous series of arched windows, while the ceiling makes a very flat or slightly con cave dome. Sir John Soane was one of the first who attempted to give importance and decorative character to skylights and ceiling windows, or windowed ceilings, as they may be termed, making them ornamental features in his interiors, varied in their design, and producing great diversity of striking effects, occasionally heightened by the light being transmitted through tinted glass, so as to diffuse a warm sunny glow over the apartment.
The offices at the Bank of England afford many studies of the kind, while his own house, in Lincoln's Inn Fields, shows what he accom plished by a similar mode of treatment, upon a very limited scale.
The form of skylights more generally used for picture galleries, libraries, and other apart ments of that class, is of the simplest kind, being lanterns, not like those in gothic archi lecture, of narrow and straight proportions but spacious and low, and occupying a consi derable surface of the ceiling. The light h admitted through the sides of the lantern which are mostly filled in with panes of glass, so as to form a window continued on ever) side, without other divisions than the bars in its framework. Of other forms of lanterns and skylights in picture-galleries and sculpture galleries, examples are furnished by those at the British Museum and the National Gallery, London, and the Fitzwilliam Museum at Cambridge, some of which are double skylights, a smaller skylight being raised over the first one.
There are a variety of other modes of light ing rooms from their ceilings, dependingin a great measure on the taste and skill of the architect, and the necessities frequently im posed by the situation or purpose of the building.
The ridge and furrow skylights (if we may thus term them) of the Exhibition Building in Hyde Park, afford the largest and simplest example ever yet constructed ; as thereof and the skylight are identical.