Heidelberg, PA Chemical Plant Explosion Dec 1917

Munition Factory Near Pittsburgh Shattered by Mistake in Mixing
Special to The Inquirer.
PITTSBURGH, Pa., Dec. 5.-- At least ten men were killed, twenty-five were injured, some probably fatally, and damage estimated at $250,000, was caused by a terrific explosion in the Aetna Chemical plant, one of the largest munition plants in this end of the State, at Heidelberg, eight miles west of here, shorly after 3 o'clock this afternoon.
The big plant, where "Tnt," one of the highest explosives being used by the allies in the European war, and lately ordered by the United States Government, was being manufactured, was shattered by the force of the explosion. Death and destruction were wrought on all sides, and buildings within a radius of several miles suffered from the blast. Fire quickly followed the explosion and for a time it appeared that the entire plant would be destroyed, but acid fumes from the wrecked portion of the plant quenched the tongues of flames within a short time.
Six Bodies Recovered
Five bodies were taken out of the wreckage within an hour after the explosion, and a sixth was found this evening. Company officials announced after the finding of the sixth body that two men were missing. Local hospitals are filled with wounded, many of whom were injured beyond recognition. Two hundred men were at work in the plant at the time of the explosion. Many men had left a few minutes before and a large number were en route to the plant from a nearby car station, when the charge let go. People in the vicinity were hurled violently to the ground and a near panic accurred in Heidelberg and at Carnegie, a mile distant. Windows in buildings two miles away were shattered, and in houses at a great distance, pictures were hurled from the walls and broken.
Federal agents and company officials were rushed to the scene soon after the explosion and are investigating to determine if the explosion was the work of German or Austrian plotters. The plant is in the heart of a big coal mining and mill district where thousands of Austrians and Germans are employed, but company officials scouted the theory that a plot was responsible for the blast, stating that an error in acid mixing was the cause.
Previous Explosions
Several explosions have occurred at other plants of the company in the same vicinity in the past year and many deaths occurred, but though many arrests were made, Federal officials were unable to attach blame to any suspects. Several months ago a chief chemist of the company was taken in custody by Federal agents and interned as an alien enemy.
Grace Lyons, telephone operator at the plant, proved herself a heroine. With one wall of the building in which her board was located, blown away, the girl stuck gamely to her post and sent out call after call for assistance until her wires were burned away and her board rendered useless.
The Philadelphia Inquirer, Philadelphia, PA 6 Dec 1917