112 THE ARCHITECTURE
OF
HUMANISM
domeofSt.Peter'sweseeaconstruction,thegrandeur
ofwhichlies preciselyinthe self-containedsense
ofits mass,andthe vigorous,;powerful contour
whichseemstocontrolandsupportitsbody. Yetactuallythe very attempt to give it thischaracter,
to addthis majestically structural effect to the
resourcesofarchitecturalart,meant that MichaelAngelo
rancounter to the scientific requirements of
a dome.)The masswhich gives sosupreme
a senseof
power
is,in
fact,weak. MichaelAngelowasforced
torelyuponagreatchaintoholditinitsplace,
andtothishissuccessors
addedfivegreatchainsmore.) Hadhe
adhered,as hismodern critics w6ulddesire,
totheByzantinetypeofdome,whichalone
wouldofitselfhave beenstructurally
sufficient, he must havecrowned St. Peter's with a mass that would
haveseemed relatively lifeless, meaningless,
and inert.Structural'truth*mighthavebeengained.
Struc-tural vividnesswould havebeen
sacrificed. It wasnot,therefore, from any
disregard of the essentialconstructiveorfunctionalsignificanceofarchitecturalbeautythathe sodesigned the
greatdome,but,onthe contrary,from
a determination tosecure
thatbeautyandtoconveyit.j Itwasonly
fromhisgraspoftherelativeplacefor
architectureofconstructionalfact and constructional appearance,
that he wasenabled,insosupreme
ameasure,tosucceed. Anditwasbytheirsenseofthesame
distinctionthatthe