The apparatus above, from page 34, powers both the dial and bells of a tower clock. The opening in the floor is for a pendulum of about 175 lbs. I find the image much more striking (pun quite intended) than those of the exterior, dials and all, of tower clocks. Besides the handsome illustrations, the book offers technical details and a description of the operation of tower clocks. There also is a directory of the companies installed tower clocks in 1911, as well as testimonials by satisfied customers.
If you are interested in historical buildings and / or engineering this book is for you.