We have a copy of that book in our museum's reference library. I'd agree with what Chas says. It's not especially rare and valuable, but it is rather hard to come across. Thomas Innes of Learney would later go on to become Lord Lyon. He was a Lord Lyon who had a special interest in tartan (and some would say even went beyond the Lyon Court's actual jurisdiction in some of his proclamations regarding tartan -- I trace the "rule" that women must wear sashes on their right shoulder back to him).

He also edited Frank Adam's benchmark work, Clans, Septs & Regiments of the Scottish Highlands, so much so that in later editions Innes of Learney is given credit as a co-author!