Part 3 — TRANSCRIBER'S NOTE.
Reading edition
1) Figure numbers (which aren't contiguous) have been preserved.
2) Part III, Chapter V. The table showing thickness of vitrified pipes reads:
4 inches diameter 1/2 inch thick
6 " " 1/16 " "
8 " " 3/4 " "
12 " " 1 " "
The thickness figure for the 6 inch pipe has been left as originally printed, but probably is incorrect (logically it should be somewhere between 1/2 inch and 3/4 inch thick).
3) A larger version of figure 1 can be viewed by clicking on the figure image.