A bee-keeper at the farmer's market in Raleigh told me that this was the last word in bee-keeping. That seems doubtful. I didn't read every word, and it was certainly a neat read in many respects, but not in the practical way I was hoping.
Langstroth, himself, was a rural Ohio Episcople priest who was given to melancholy and turned to bees as an expression of the now-obsolere amature naturalist. (See Mendel, et al.) In all the ways that the book reflectsthat tradition (as well as the type setting and wood cuts) it's a great book. As a field manual for someone wanting to keep bees, it was less helpful.