There are two reference books that would be of interest to you. See the Callows of Ballaterson East, page 307 of "A History of Kirk Maughold" by J.W. & C.K. Radcliffe. It is out of print but available at the MNH Library in Douglas and sometimes at used book stores such as Abes which is online.

The other reference is "Life at the Lhen" a booklet by Wm. Kinread. It is available free online by googling the title. It was first published in 1933 but recalls events from the 1890's. Check pages 7, 8 and 19.

Two brothers of Thomas Callow (1822-1906) emigrated to Ohio. They were James Callow(1825-1854) and William Callow (1828-1907) who married Electra Williams. Descendants of this William Callow have been traced by someone at least 4 generations.

What is your connection with Captain John?