Strange Cavern in the Allegheny

The following account was given in a letter which was submitted to AMAZING STORIES science fiction/science fact magazine, Dec. 1946 issue, p. 162. The letter was from a George A. Lehew of (at the time) 1918 W. Newport Ave., Chicago, ILL. Lehew wrote:

"Sirs... I have been a reader of AMAZING STORIES for a very long time... I too, know of one of these entrances into the world below. It is about fifty miles south of Pittsburgh, Pa., in the first range of the Allegheny Mountains. My experiment with the caves have been only partial explorations, consisting of traveling about a mile and a quarter down into the cave itself, and returning. The cave IS VENTILATED from below, and stays at a constant 50 degrees no matter what the outside temperature may be. It is a series of rooms or galleries with narrow passages from one to another. In about the sixth room down, there is a large tree trunk which could not have come from the surface as the stratosphere (sic) is almost completely free from local fault; and it could never have come DOWN through the openings in the cave itself as they were small at the top, and kept getting progressively larger as they got deeper.

"I traveled down as long as I could find comparatively easy travel -- about 45 degree descent all the way--and finally came to what I thought must be the end of the cave, for I could see no more openings into rooms, but on closer examination found instead a bore, about six feet across, straight down into solid rock. I turned my flash downward and could see that it must have gone straight down for at least a hundred feet, the sides were perfectly smooth, and the shaft, or bore, in a perfect round -- no apparent irregularities anywhere--I had no way of descending any further, so I retraced my steps back up through the different rooms to the top of the mountain where the cave opens into this world. I made discreet inquiries of several old timers in that region, and found that in 1915, or about that year, six surveyors took gear and equipment, and spent a month in exploration of the cave, going 18 miles from the entrance, and down almost five miles below sea level. I have never gone back, but I hope to some day in the future, with escort, equipment, and supplies. I'd certainly love to see the machine that made that bore! If you have any information on other caves in that area, let me know -- they too may tie in with this one, though if they do, their connections are very deep. Also, if you can, please describe the equipment that made that vertical shaft. Oh, yes, one more interesting item -- the surveyors in their exploration of the cave, distinctly heard the rumble of MACHINERY -- but their calculations proved they were nowhere near a large city (surface), and they were too deep for surface noises otherwise. What is the answer?"

T