Eddystone, Pennsylvania (WHTM) On April 6, 1917, the United States officially entered World War I with a declaration of war against Germany.

Four days later, at Eddystone, Pennsylvania, a munitions factory blew up. The 133 people, mostly women, who died in the blast have been called America’s first WWI casualties.

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Eddystone Borough is located along the Delaware River, south and west of Philadelphia. It was here that the Baldwin Locomotive Works erected the Eddystone Armory. Why would a locomotive company be manufacturing munitions, you ask? Well, when WWI broke out in 1914, Great Britain, France, and Russia repurposed their domestic industries to produce materials of war, and contracted with Baldwin to provide locomotives.

Then Britain contracted with the Remington Company to produce rifles, and Remington subcontracted part of the work to Baldwin. And when their need for munitions outstripped their industrial capacity, Britain and France (and later Russia) also contracted with Baldwin to produce artillery shells.

The amount of work far exceeded the capacity of Baldwin’s Philadelphia plant, so they constructed two new factory buildings at Eddystone, one for rifles, and one for munitions. They were operated by the Eddystone Ammunition Corporation, a subsidiary company created by Baldwin. 

The munitions manufactured at Eddystone were shrapnel shells, an anti-personnel device. They look much like a typical artillery shell, with a brass cartridge holding a propellant (usually black powder) and a shell. But instead of carrying an explosive like most shells, the shrapnel shell was full of round balls, or bullets. A timer fuse would cause the shell to burst in midair, showering the victims below with bullets. The Eddystone plant built the entire shell, from building the shell to shaping the brass cartridge – and filling the cartridge with black powder. Most of this work was being done by women and girls.

At about 10 a.m. on April 10, 1917, a huge explosion demolished the “F” Building, where the shells were manufactured. The factory had about 18 tons of black powder stored in it, and it’s believed the powder somehow ignited. The main explosion then triggered a series of smaller blasts, as the individual shells began going off, spraying the area with shrapnel bullets. The shrapnel blasts injured not only workers but many first responders, including a fireman who lost a leg to a bullet.

People turned out en masse to help; police, fire, doctors, nurses, and just plain ol’ ordinary citizens who wanted to do anything they could.

100 cadets of the nearby Pennsylvania Military College rushed to the scene, and were put on crowd control – a crowd that rapidly grew as frantic relatives arrived, desperate to find out what happened to family members.

By 11 a.m. local hospitals filled beyond capacity, and the Chester Armory was turned into a temporary hospital. National Guardsmen, members of the Red Cross, and Boy Scouts set up cots in the drill hall.

Physicians called for blankets, and residents brought blankets, sheets, and cloth for bandages. Nearby homeowners brought hot water in any container they could find. Hot food and coffee flowed in from individuals and restaurants.

In all 133 died in the explosion, mostly women. Many others suffered severe injuries and/or burns. Of the dead 55 could not be identified, and were buried in a mass grave at Chester Rural Cemetery. The site is marked with a monument.

For many the important question wasn’t “How did this happen?” but “Who did this?” Suspicions that it was an act of sabotage were voiced almost immediately. The chief suspect, not surprisingly, was Germany, given that we’d just declared war with them. But others wanted to blame Russia. The shells being bought from America were going to the White Russians, supporters of the Czar who were locked in a civil war with the revolutionary Red Russians.

But there was a third possibility raised, that it was caused by a problem in the plant. There was a report machinery used to shake the brass casings so the black powder would settle in them had been malfunctioning, and suggesting a short circuit set off the blast.

In the end, the cause of the explosion was never determined. The plant reopened in just a few weeks, and more people (mostly women) applied for jobs than were available.

After the war, the assembly lines for rifles and artillery shells shut down, and the factories started manufacturing locomotives for Baldwin.