Just came upon your post. I am a genealogist based in Glasgow, Scotland. I am carrying out research for USA residing descendants of David Boyle, whom you say pioneered early ammonia compression refrigeration.
Here is what I have on him: I took the said descendants to David Boyle's birthplace at Johnstone, Renfrewshire, Scotland, in 2010 and am currently carrying out more research for the. Whilst some of their family sources say that David Boyle was resident in the Chicago area after 1865, other sources, including yours place him elsewhere?
My research shows that he was born at Johnstone, Renfrewshire c.1837, to David Boyle (b.c.1800, m.1832 Johnstone, d. 1880 Kilmacolm, Renfrewshire) and Agnes Hutton (b.c.1810)). David Boyle married c.1866 to Margaretta Henry, of Irish birth (I am still working on this line). He died, according to my clients, 1891, Mobile AL. My client is his great-granddaughter, a woman in her 70s. Anything you have re his time in your area would be of interest.