The petrified child in the family of J.A. Kinsley, of New Philadelphia, continues to attract general attention, and is considered by all who have seen it to be the wonder of wonders. The hardness has gradually spread over the entire body, some portions being so hard that not the slightest indentation can be made. The case is said to be without parallel in the history of the country, and the singular disease has thus far baffled all medical skill. How the child can live in this solidified state is the greatest mystery. The parents are greatly grieved over its sad affliction, and are doing everything in their power for its relief.I'm not a medical expert, so there may be a better candidate, but I would submit the possibility that this was a case of fibrodysplasia ossificans progressiva (FOP), a degenerative disorder in which the muscles turn to bone, paralyzing the victim. The Mütter Museum in Philadelphia has in its collection the skeleton of an individual named Harry Eastlack, who died in 1973 at age 40. At the end of his life, Eastlack was able to move only his lips. However, from what I've been able to gather it would be extremely rare (though nothing's impossible) for FOP to be so pronounced in childhood.
The skeptic in me, though, is also doubting the account somewhat, based on a singular lack of detail about the afflicted child: no name, sex, or even age is given.
UPDATE: The doctors at the time labelled this an advanced case of scleroderma. This also took place in Ohio, not Pennsylvania.