Hi Cheryl,
Interesting, the record of James Boyle in 1841 in Salford/Manchester, but it can't be "my" James. He was only born in 1827 in Leeds, so would have only been 14 in 1841 ... possibly apprenticing at the time, but surely too young to appear in a trade directory.
James' father was Archibald, and a joiner, but could the 1841 James possibly be "my" James' grandfather? As you say, trades tend to run in families, and I've been unable to locate Archibald before he turns up in Rothwell, Yorks, to marry a Grace Watson in 1822. I've only located two of their children - James and an older sister, so James could have been their oldest son, and named after the grandfather. Purely speculative, of course, but very interesting!
All the best
Tim