1608
THEORY AND PRACTICE OF ENGINEERING.
Book II.
Westminster Abbey , commenced in the year 1245, is in that style which for many yearsprevailed in France : the fine church at St. Denys, near Paris , is exactly similar in all itsdetail. The windows are wide, divided by mullions,and have their heads filled in with plain circles, theorigin of the cusp, or that kind of decoration whichevery pointed arch afterwards received. This style,which succeeded the Lancet, is found throughoutEngland, and many of the parish churches exhibitfine examples of it. Stone Church, in Kent, ofwhich the writer has published an account, may becited as one of the best; its ornament shows theskill and taste that prevailed among the free-masons at that period. Salisbury, Wells, and \orkCathedrals abound with rich foliage and sculpturesof the highest merit executed at the same time, andit is wonderful to observe to what a state of perfec-tion the artists of this country had arrived. Theeffects of the chisel of the Pisan school were dis-played upon marble, but our sculptors worked uponan inferior material; yet the draperies of theirfigures, as seen in the front at Wells, and else-where, are quite equal to those wrought bythe pupils of Italian masters at the same time.
The circle and its intersections at this period werealone employed for the plans of piers, sections ofmouldings, and the filling in of windows and.doorways: from them we trace the origin of thestyle which immediately succeeded.
The cathedrals of Cologne, Amiens , Beauvais, theSainte Chapelle at Paris , and numerous other ex-amples on the continent, exhibit the same propor-tions and style with that of Westminster ; the loftypointed arches, which rest upon the main cluster, aredecorated with numerous small mouldings ; the tri-forium, in some instances glazed, have their pointedarches filled in with trefoils, cinquefoils, or sexfoils,and the clerestory, carried up to the very apex ofthe vaulting, is similarly adorned. Westminster Abbey is one of the finest examples of buildingexecuted in the thirteenth century.
Tracery and Geometric Forms —To comprehendthoroughly the principles which directed the free-masons of the middle ages in the execution ofall their works would require far greater illustra-tion than can be bestowed upon the subject inthe present volume: it must be sufficient if wepoint out a few which influenced the design ofsome of their best examples, and show that it is aperfectly erroneous opinion to suppose they wereexecuted without a thorough knowledge of certainrules, originating with themselves, and perfected bya constant study of what was not only useful, butproductive of the best effect. Those who inquireinto this subject must collect the data upon whichan opinion can be formed, for it is scarcely possible,without positive measurement, to arrive at any con-clusion upon the matter: the admirer of the Greek,or the commentator upon Vitruvius , alone canscarcely hope to be successful : it is true that inone of the early printed Italian editions of thevaluable author quoted, there are several dia-grams which seem to point to the subject, butthe student will find only the nucleus aroundwhich the lovers of geometry in the middle agesarranged their varying and beautiful forms ; this is the equilateral triangle, and byinclosing the plan, section, or elevation of a building within it, the several proportionscan be accurately measured, and if sub-divided into a number, either of the triangleswould show the proportion it bore to the whole area.
IM