January 15, 1919. A bulging, overheated storage tank burst, spewing a towering wave of fast-flowing molasses into Boston’s busiest commercial district, killing 21, injuring 150, and wreaking tsunami-style devastation. The incongruity of “molasses” and “disaster” tends to rob the legendary Great Molasses Flood of its gravitas. Better viewed as a horrific industrial accident, it offers up five lessons worth mulling over on its 96th anniversary. 1. Heed warning signs. The massive tank, which held more than 2 million gallons, leaked so badly that neighborhood kids used to scoop up the puddles with pails. The owner, U.S. Industrial Alcohol (USIA) Company, chose camouflage as a solution when it repainted the gray tank to match the…