22. ARABIAN ORNAMENTATION.
I do not mean what I have here said of the Inventive power of the Arab to be understood as in the least applying to the detestable ornamentation of the Alhambra.[105] The Alhambra is no more characteristic of Arab work, than Milan Cathedral is of Gothic: it is a late building, a work of the Spanish dynasty in its last decline, and its ornamentation is fit for nothing but to be transferred to patterns of carpets or bindings of books, together with their marbling, and mottling, and other mechanical recommendations. The Alhambra ornament has of late been largely used in shop-fronts, to the no small detriment of Regent Street and Oxford Street.
23. VARIETIES OF CHAMFER.
Let B A C, [Fig. LXXII.], be the original angle of the wall. Inscribe within it a circle, p Q N p, of the size of the bead required, touching A B, A C, in p, p; join p, p, and draw B C parallel to it, touching the circle.
Then the lines B C, p p are the limits of the possible chamfers constructed with curves struck either from centre A, as the line Q q, N d, r u, g c, &c., or from any other point chosen as a centre in the direction Q A produced: and also of all chamfers in straight lines, as a b, e f. There are, of course, an infinite number of chamfers to be struck between B C and p p, from every point in Q A produced to infinity; thus we have infinity multiplied into infinity to express the number of possible chamfers of this species, which are peculiarly Italian chamfers; together with another singly infinite group of the straight chamfers, a b, e f, &c., of which the one formed by the line a b, passing through the centre of the circle, is the universal early Gothic chamfer of Venice.
Again. Either on the line A C, or on any other lines A l or A m, radiating from A, any number of centres may be taken, from which, with any radii not greater than the distance between such points and Q, an infinite number of curves may be struck, such as t u, r s, N n (all which are here struck from centres on the line A C). These lines represent the great class of the northern chamfers, of which the number is infinity raised to its fourth power, but of which the curve N n (for northern) represents the average condition; the shallower chamfers of the same group, r s, t u, &c., occurring often in Italy. The lines r u, t u, and a b may be taken approximating to the most frequent conditions of the southern chamfer.
| Fig. LXXII. |
It is evident that the chords of any of these curves will give a relative group of rectilinear chamfers, occurring both in the North and South; but the rectilinear chamfers, I think, invariably fall within the line Q C, and are either parallel with it, or inclined to A C at an angle greater than A C Q, and often perpendicular to it; but never inclined to it at an angle less than A C Q.