316 



GOTHIC ARCHITECTURE 



difficulty of the yielding of the haunches in the 

 semicircular arch. They were thus led to the adop- 

 tion of the pointed form for their transverse arches 

 as a structural expedient, and still retained the 

 semicircular form in the groins. The next question 

 which engaged attention, and the solution of which 

 led to the further use of the pointed arch, was the 



Fig. 4. 



vaulting of oblong spaces. This had been tried 

 with semicircular arches, but it was found that 

 with that form the vault would require to be very 

 much domed the diameter of the arches c, c ( fig. 

 1 ) being so much smaller than that of a, a 

 whereas by using pointed arches, of different 

 radii, for the transverse and side arches all might 

 be kept to about the same height. This is 

 more fully explained by fig. 5. If AB be the dia- 

 meter of the transverse arch ( aa, fig. 1 ) and AC 

 that of the side arches (cc), it is clear that the 

 semicircular side arch ADC cannot reach the height 



B B' A 7 AT 



Fig. 6. 



of the transverse arch AEB, even when stilted as at 

 D'. But in the pointed arch CEB the same dia- 

 meter rises to very nearly the height of the trans- 

 verse arch. The pointed arches ACB and A'CB' 

 (fig. 6) show how easily arches of this form, what- 

 ever their diameter, can be carried to the same 

 height. By the introduction of this new form of 

 arch the vaulting was strengthened, and the 

 thrust brought to bear steadily on single points. 



We have now traced the history of vaulting from 

 the time of the Romans to the 12th century, when 

 the principles of Gothic pointed vaulting were fully 

 developed ; and we have dwelt particularly on this 

 subject, because it includes the principles which 

 regulated the whole of the Gothic style. Gothic 

 was not the invention of an individual, but a 

 necessary growth a gradual development from 

 structural requirement. This is clearly the case 

 with regard to the vaulting, as we have en- 

 deavoured to show above, and the same might be 

 proved regarding every member of the style. Thus 

 it might be shown how the ribs became gradually 

 more decided, expressing the part they bore in the 

 support of the roof ; how the nave piers or pillars 

 were subdivided by degrees into parts, each shaft 

 bearing on a separate cap a separate member of the 

 vaulting; how the buttresses were developed as 



they were required to resist the thrust of the groins 

 concentrated on points ; and how the flying but- 

 tresses were forced upon the Gothic architects much 

 against their will, as a mode of supporting the 

 arches of the roof. 



The history of the flying buttress is curious. The 

 thrust of the tunnel-vault was sometimes resisted 

 by half- tunnel-vaults over the side-aisles (see fig. 4). 

 The latter, therefore, required to be high, and a 

 gallery was usually introduced. In the Narthex at 

 Vezelay ( fig. 7 ) we have this gallery with the vault- 

 ing used as a counterpoise to thatof the central vault. 

 This is a fine example of vaulting in the transition 

 state, that of the gallery resisting the main vault, 

 as in fig. 4, and being at the same time groined. 



Fig. 7. 



This leaves rather a weak point opposite the trans- 

 verse arches, to strengthen which the part of the 

 semi-tunnel-vault (fig. 4) opposite the transverse 

 arch is left standing, although the rest is altered by 

 the groining. At Vezelay ( fig. 7 ) this arch timidly 

 shows itself as a small flying buttress above the 

 roof. It is easy to see how this idea would gradu- 

 ally develop itself into the bold ' arc-boutant ' of a 

 later date. The galleries were, in later examples, 

 dispensed with to admit of larger clerestory windows, 

 and the flying buttresses were left standing free. 

 The architects finding them indispensable, then 

 turned their attention to render them ornamental. 

 Pinnacles may also be shown to owe their origin 

 to their use ; they acted as weights to steady the 

 buttresses and piers. We shall, under their 

 separate heads, point out how each element, of 

 Gothic architecture was in the strictest sense con- 

 structional, the decoration being in harmony with 

 its actual use, or as Pugin has said, ' decorated 

 construction, not constructed decoration.' 



The full development of Gothic vaulting, which 

 was the forerunner of the whole style, was first 

 carried out in the royal domain in France about 

 the middle of the 12th century. ^ 



The Normans had settled in the north of France 

 more than two centuries before this, and had applied 

 their talents and the fruit of their conquests to the 

 building of splendid temples in honour of their 

 victories. In doing so they followed out the round- 

 arched style, and brought it forward by a great 

 stride towards true Gothic. See NORMAN ARCHI- 

 TECTURE. 



South of the royal domain, in Burgundy, there 

 had existed for centuries great establishments of 

 monks, famous for their architecture. The abbey 

 of Cluny was their central seat, whenuo they sent 

 out colonie^, and built abbeys after tl ; ^ model of 

 the parent one. The style in which t^jy worked 

 was also an advanced Romanesque, bt t different 



