The founder and owner of James McKay & Co of Pittsburgh, a manufacturer of metal chains, he was also active in oil and gas development, with one of the earliest producing properties in Pennsylvania.

This produced about three thousand dollars per day, but owing to the inadequate facilities of the time and the incompetency in handling the outflow, the greater part of this was lost.

The firm was changed to a stock company in 1905, and Mr. McKay retired, turning over all his interests to his three sons, the two mentioned above and Thomas J.

He was an extensive property owner in Pittsburgh, as well as in West Virginia, Kentucky, Colorado, Idaho, New Mexico, Arizona and California.

During the 1880s, the McKays purchased an island near the then-newly settled resort area of Beaumaris on Lake Muskoka in Ontario.

The island, named "Fairholm", was conceived as a family enclave for the summer, much like similar developments during this era in the Adirondack Mountains.