Chap. XXXI.
PRINCIPLES OF PROPORTION.
1605
at Salisbury. The masonry of the arches is admi-rably constructed, and the joints all radiate to a com-mon centre.
The total width of this cathedral from face to faceof the buttress is 86 feet 5 inches, and that ofthe nave 31 feet 10 inches, instead of 28 feet 9±inches, as it would have been if a third had beenadopted; the side aisles are also diminished in conse-quence, being only 13 feet 7^ inches in the clear;they are, however, equal to the buttress, outerwall, and main pillar added together, the first pro-jecting 2 feet 8 inches, the second or outer wallbeing 6 feet in thickness, and the piers 5 feet diame-ter; whilst the width of the side aisle measures 13feet 7£ inches, an approximation sufficiently near tosuppose that the proportions of thirds was still adoptedm practice. The nave has been increased at theexpense of the side aisles, and its height is 68 feet9 inches to the top of the vaulting from the pave-ment.
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Fig. 3005.
TRIFORIUM, INSIDE.
Chapter House atWells, erected betweenthe years 1293 and1302, is an octangularbuilding of greatbeauty. A sectionthrough the but-tresses shows thattwo equilateral tri-angles crossing eachother have determinedthe mass and void,which are in the pro-portion of one to two,or the thickness of thetwo walls is equal toone-third the entirediameter: the baseline of the triangle,on which the supportsof the crypt are placed,clearly indicates thisarrangement. Of thetwelve equilateral tri-a ngles comprised in theParallelogram formedb y uniting the bases°f the two larger, eachouter wall and buttressoccupy two, or thewo walls and theirbuttresses four of thetwelve divisions,caving eight for the8 pace between them.
Fig. 3007. CHARTER-HOUSE AT WELLS.
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