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ftSOURCES:^ LINDSAYS.^ COOK,^ BALLSTATE^ U.;^ MAXIME^L’HÉRITIER,^PARIS^8U.;^STEPHEN^ MURRAY,^COLUMBIA^ U.;^ TONYAM.^OHNSTAD,LORENZO^ DE^ ALMEIDA,^ CATHOLICU.^ OF^ AMERICA;^ ROXANE^ROUSSEL;^DANY^ SANDRONET^AL.,NOTREDAME^ CATHEDRAL,^2020;^ PHILIPPE^VILLENEUVE,^ MINISTÈRE^ DE^ LACULTURE;^ LABORATOIRE^ DERECHERCHEDES^ MONUMENTSHISTORIQUES:^ THIERRYZIMMER;^AURÉLIAAZÉMA,^ DELPHINESYVILAY(METAL);^ WITOLD^ NOWIK,^MARIE^PARANT(PAINTING);^CLAUDINE^LOISEL,^ BARBARA^TRICHEREAU(STAINED^ GLASS);^LISECADOT- LER
OUX,^ JEAN- DID
IER^MERTZ^(STONE);^ EMMANUEL^MAURIN(WOOD)3 D^ MODEL:^ CHANTIERSCIENTIFIQUE^NOTRE-DAME^ DEPARIS;^ CNRS;^FRENCHMINISTRY^ OF^ CULTURE;GEA;^ LIFE^3 D;^ MAP;^ THE^LATE^ANDREWTALLON,^ VASSAR^COLLEGE^
MURAL^ PHOTO:JOSEPHANDALOROFRAGILEARTLeadresiduewill^bedusted^offofNotre^Dame’s^130stainedglass^windows,^ barely^damaged^ duringthe^fire.^The^ uppermost^25windows^ wereremoved^ to^ prevent^accidentalbreakage.CLUES^ IN^STONEHeat^damaged^30percent^ofthe^ topareaofthe^walls^(orangelines).^ When^limestoneisheated,^it^changes^ color,^ revealing^different^ levels^of^damage.^
THE^ SOUNDOF^ HISTORY^The^ “voice”^ that^ reverberatedfrom^the^ grand^ organ^ wassilenced^after^lead^ dust^ settled^within^the^instrument.^ A
n^ effort^tocarefully^cleanits8 ,000 pipes^ isunder^ way.REVIVINGMURALSPreservationists^tested^ myriadsolvents^ in^ thelab.^Theyfound^ agel^thatcouldbeappliedtovacuumedmurals^ to^ ridthemofleadand^pollution^ without^ damagingthem.^
A^ layer^of^gypsumplaster^ laid^as^a^ firestop^ in^ the18
00
s^slowed^ the20
19
fire.^
Fixing^ thestone^Expertsdrill^ small^ holes^into^ cracked^ stones,insertpins,and^ fill^ them^with^specialized^ grout^as^reinforcement.Stones^ are^cataloged^and^ scanned^ as^ three-^dimensional^ images.
Restoring^the^ archesMore^than^80 percent^of^thefallen^ stones^were^recovered.^They’ll^berepaired,^or^new^stonescut^ to^ original^specifications.^Models,3 D
printed,^ test^theprobable^positionofeach^stonein^an^arch.New^ stones^ will^ be^ cut^to^replace^ those^lost^ or^structurallyunsound.
Hard,densestones^ wereused^ for^arches,^theskeletonofthebuilding.
Thin,light^stones^ wereused^ as^ web-
bing^ between^thearches.