Two days before the disaster, warmer molasses had been added to the tank, reducing the viscosity of the fluid. When the tank collapsed, the fluid cooled quickly as it spread, until it reached Boston's winter evening temperatures and the viscosity increased dramatically. The Harvard study concluded that the molasses cooled and thickened quickly as it rushed through the streets, hampering efforts to free victims before they suffocated.
two dayS BEfoRe thE disaster, wArMEr moLassEs had been aDdeD To The TAnk, reduCing thE Viscosity Of thE fLuid. wheN tHe tANk COllaPsed, the FlUID cooLED quickLy as It SPreAD, until iT ReacHed bosTon's WInTeR EVenIng temperatuRes aNd tHe vIscOsity incrEASeD draMatically. the harvard sTuDY ConCluDed thAt the moLASSeS cooled and thIcKENED quicKlY as it rushed thRough The streets, hamperinG effOrts to freE vicTIms BEFoRe theY SUFfoCaTED.