On Oct. 4, 1918 a huge explosion rocked New Jersey.

According to the book, On This Day In New Jersey History, The T.A. Gillespie Shell Loading Plant in Sayreville exploded, “setting off three days of detonations” in Sayreville and South Amboy. Most reports put the number of dead at 100, with hundreds more injured. The number of dead is unclear because no comprehensive list of employees existed, plus, some of those closest to the blast were incinerated, making identification impossible.

The plant, also known as the Morgan Depot, was producing 32,000 artillery shells a day for the American war effort in World War I. It is estimated that the volume of the ammunition that exploded would have supplied the Western Front (in WWII) for sixth months (the war ended a month after the explosion). The initial and subsequent blasts leveled 300 buildings in the surrounding area, forcing evacuations in Sayreville, South Amboy, and Perth Amboy; martial law was declared to take control of the panic-filled situation.

The explosions continued for three days with the blasts felt as far away as Manhattan and rattling windows in Newark. “Hundreds of loaded shells were set off by the flames and soared through the air like monster rockets, exploding in the streets and over the roofs.”

Damages were estimated to be $18 million in 1918 dollars, which would be around $300 million today. The blast involved so much ordnance and covered such a wide area that shrapnel from the explosion was unearthed as recently as 2007. German espionage was originally suspected as the cause of the disaster but a subsequent inquiry found no evidence of that and concluded it was most likely worker error.

The post above reflects the thoughts and observations of New Jersey 101.5 talk show host Bill Doyle. Any opinions expressed are Bill Doyle's own.

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