The ancestry on the Dorothy we now believe to be the following.
Only 5 units of the 50ton Whitcomb design were ever
built, all at Eddystone, PA. They carried the rectangular builder's plate of Baldwin Lima Hamilton and even were included into the Baldwin serial numbers.(Note: Some Whitcomb units built at Eddystone had BLH plates too, but used the several different Whitcomb serials to designate different types of locos).
At least 4 of the 5 are known to still exist. The 5th could be lurking out there somewhere undetected so far.
Dorothy has been identified as built new for Standard Slag
Co. as #45 for their slag plant at Mingo Jct, Ohio. After they shut down, the unit was next seen at a loco dealer being overhauled, somewhere in Minnesota. Supposedly pictures exist of it on their property.
Next it showed up at Cargill and was used at a couple plants. The serial is BLH 76111 4/55.
Of the 5 units built, 3 were used in Ohio. Standard Slag owned another unit and this is the one that has vanished. Babcock Wilcox had a unit at Barberton,Ohio and it is still at work here in Warren,Ohio at present owner Luntz Steel Co., a scrap yard.
I'd like to extend a major thanks to Frank Vollhardt for his invaluable assistance in tracking down Dorothy's family tree.