Subterranean Centaur Scare

It is early March of 1913 (probably the 7th, to be exact) - and hundreds of sweaty men are bustling about in the Chicksaw Mine under Kittanning, Pennsylvania. They are presumably quite desperate to see the sunlight outside, but the circumstances in which they would be forced out into the light in just a moment would haunt them for the rest of their days. Violent hoofbeats and a ghostly light seep their way through the subterranean gloom, signalling the fateful arrival of a bizarre spectre unlike any other...

The Kittanning Incident

The hoofbeats (which I have presumed must've been present) got louder and louder as the surreal form moved from room to room in the mine, ordering all the workmen to abandon their tools and leave the mine in a 'sepulchral voice'. Terrified and likely utterly dumbfounded at the sight, the workers promptly did as they were told by the incomprehensible creature - pouring from the entrance of the mine in droves, perhaps setting a new record for the speed at which a mine could be evacuated. 

The illustration that appeared in Fortean Times accompanying this story.

As my description of hooves might imply, this entity was not your average humanoid ghost. No, instead it was described as having a torso like that of 'an emaciated man' and the lower body of a horse. It was a centaur, to put it simply. In one hand, it carried an odd object which was compared to a dinner pail - from which issued 'lurid gleams' of phantasmal light. 

One John Martel was working as the driver of the mine motor, and was allegedly at his place atop the machine when the spectre came for him. It apparently manifested out of nowhere, before pointing its bony fingers at him and uttering a single word - GO. Martel found himself unable to move for a moment, being literally paralysed with sheer terror. As soon as he was once again capable of movement, he screamed in horror and dashed away from the creature. He sprinted along the tracks towards the light streaming in from the mine's entrance - only momentarily glancing back the way he came to see the motor in hot pursuit, now apparently being somehow driven by the centaur. By the time Martel finally emerged into the safety of daylight, he turned back once more to see that the motor (now driverless) was close behind him. He had only just made it. 

The miners refused to go to work the next day, and as of the time that the story was originally published (in the March 9th, 1913 edition of The Philadelphia Enquirer), it had yet to be decided how business should proceed in the Chickasaw Mine. The centaur was apparently seen as some kind of ill omen. One of my sources speculated that perhaps this was an incredibly bizarre excuse for the miners to escape work - but surely there would be less fantastical and more believable stories to be made up for this purpose? And presumably to be employed more effectively? 

Sources

I originally found this story in an issue of Fortean Times, which sadly only included a very much abbreviated version of the tale and didn't offer me any realistic way to track down the original source or even any more information. Eventually, fellow researcher Albert Rosales was able to find the full story in various newspaper clippings. I was also able to find another source online that repeated what the newspaper clippings said. Here is that source.

The most extensive (and sadly least clearly scanned) clipping on the topic.