BAS

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BAS

anciently raised over the body of a distinguished person.Barrows are considered as the most ancient sepulchral monu-ments in the world.

BAS-KELIEF. See Basso Eelievo.

BASALT, a hard dark-coloured rock, of igneous origin,formed of columnar or stratified parts, very useful in building,paving, &c. Basalt , when calcined and pulverized, is an ex-cellent substitute for puzzolana, in the composition of mortar:by undergoing these operations, it acquires the property ofhardening under water.

BASE, in architecture, is the lowermost part of a body,consisting of one, or an assemblage of parts, taken in itsaltitude, being separated from its upper part, which is a nakedor plain surface.

Base of a Boom, is the lower projecting part, consistingof two portions, the lower of which is a plain board adjoiningthe floor, called the plinth, and the upper consists of one ormore mouldings, which, taken collectively, are called thebase-mouldings. The plinth in the best work is tonguedinto a groove in the floor, by which means, the diminutionj of breadth in the shrinking never shows any aperture, orj j cavity, between its under edge and the floor ; and the upper| ; edge of the plinth is rebated upon the base. Bedrooms,

I lobbies, passages, and staircases, are often finished withoutj the dado and surbase, as also sometimes vestibules and halls,j Booms which have pavement-floors, have their bases, ini general, consisting of stone plinths, and wooden base-mould-' ings, which are not so liable to be broken as stoneI mouldings.

BASEMENT, the lowest story of a building, on whichj an order is placed, consisting of a base, die, and cornice.

The choragic monument of Lysicrates is a beautiful example1 of an antique basement. In modern buildings, the height' of the basement will vary according to the character of the1 edifice: it is proper, however, to make the basement nohigher than the order of the next story, for this would bemaking the base of more importance in the composition thanthe body to be supported. If the cellar story is the base-ment, and if the height does not exceed five or six feet atthe most, it may be plain, or with rustics, or formed into acontinued pedestal ; but if the basement is on the groundstory, the usual manner of decorating it is with rustics, sup-ported on a base, and surmounted with a crowning stringcourse: the base may be either a plain or mouldedplinth ; and the cornice may either have a platband ormouldings under it, or may form a cornice of smallprojection. The rustics are either of a rectangular ortriangular section, supposing one of the sides of thesesections to be a line extending across the front of the joints.The joints of the rustics may be from one-eighth to a tenthpart of their height ; the depth of the triangular joints maybe half their breadth ; that is, making the two planes bywhich they are formed a right angle; and the depth of therectangular from one-fourth to one-third of their breadth.The ancients always marked both directions of the jointsof the rustics, whereas the moderns employ not only theancient manner, but sometimes make them with horizontaljoints alone ; the latter, however, represent rather a boardedsurface than that of a stone wall, which must have two direc-tions of joints.

The height of the string course should not exceed theheight of a rustic with its joints ; nor the plinth, orzocholo, be less than the height of the string course.When the basement is perforated with arcades, the impostsof the arches may be a plat-band, which may be equal tothe height of a rustic, exclusive of the joint. When thestring course is a cornice, the base may be moulded,

the projection of the cornice being two-thirds of its height,so as to be less prominent than that which finishes thebuilding. The height of the cornice may be about one-eighteenth part of the height of the basement, and that ofthe base, about twice as much, divided into six parts, of whichthe lower five-sixths form the plinths, and the upper sixththe mouldings.

BASIL, among carpenters and joiners, the iron side ofthe angle of a tool, ground so as to bring the end of the toolto a cutting edge. If the angle be very thin, the tool willcut more freely, but is in danger of breaking into notches,if not duly tempered : to remedy this, it is sometimes foundnecessary to grind it thicker.

BASILICA (from fianXevc, king , and oikoq, house, signi-fying royal house) a building originally used as a court ofjustice. Among the Bomans, it was a large hall adjoiningthe forum, where the magistrates judged the people undercover, which distinguished it from the fora, where they heldtheir sittings in the open air. Basilicas were in planparallelogrammic, divided lengthwise into three or moreaisles, the centre one of which was called the testudo, andthose at the sides porticos. The testudo was covered by aroof supported on two rows of columns, situate on eitherside between it and the adjoining porticos. These porticoswere divided vertically by two galleries, one above the other,which ran round three sides of the building, and were coveredby a lean-to roof, meeting the above-named columnsbelow their capitals, so as to leave an open space betweenthe roofs of the porticos and the testudo, for the admissionof light. At that end of the testudo where the gallery wasdiscontinued, stood a raised platform, on which was placedthe tribunal for the magistrate. The above is as clearly ascan be discovered, a correct description of the ancientbasilica, and agrees in all its principal features with a build-ing which has been discovered in the ruins of Pompeii .

The proportions of these edifices are given by Vitruvius as follows :—“ The breadth,” he says, “ is not to be lessthan a third, nor more than the half of the length, unlessthe nature of the place opposes the proportion, and obligesthe symmetry to be different; but if the basilica has toomuch length, chalcidicce (supposed to be apartmentson the sides of the tribunal, separated from the body bya partition) are taken off the ends, as in the basilica of JuliaAquiliana. The columns of the basilica are made as highas the porticus is broad; which again is equal to the third partof the space in the middle. The upper columns are less thanthe lower, as above written. The pluteum (a kind of podiumor continued pedestal) which is between the upper columns,should also be made a fourth part less than the same columns,that those who walk on the floor above, may not be seen bythe negotiators below. The epistylium, zophurus, and coronabelow, are proportioned to the columns, as in my thirdbook.

“ Nor will basilicas such as that at the colony of Julia ofFanum, which I designed and executed, have less dignityand beauty, the proportions and symmetry of which are asfollows: The middle testudo, between the columns, is onehundred and twenty feet long, and sixty feet broad. Theporticus around the testudo, between the walls and columns,is twenty feet broad. The height of the continued columns,including their capitals, is fifty feet, and the thickness five,having behind them parastatse (attached pilasters) twentyfeet high, two feet and a half broad, and one foot and a halfthick, which sustain the beams that bear the floors of theporticus. Above these are other parastatae, eighteen feethigh, two feet broad, and a foot tjiick, which also receivebeams sustaining the canthers of the porticus, which are laid

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