Hi to Jean C-

I just found your actual question burried in the post. We don't know the age at demise for the elder John T. Gill, my great, great, great grandfather. My great grandfather was Kermode Fredrick Gill, which I would have known if I'd asked my mother before posting. It was he who actually built the Terminal Tower, as well as the first phase of the Lincoln Memorial. He passed before my time, sadly, at 82 years (I'm fairly sure), as successive generations have tended to marry a bit late.

Thanks again!
Stephen Fox