Two headers (Kitchen-Sink Drainage and Cesspools) were added to the Table
of Contents based on their formatting in the text. Minor typos have been
corrected. Illustrations were moved to prevent splitting paragraphs.
Figure 21. was moved adjacent to the directions and specifications on Page
32. Due to space considerations in the text only version, emphasis of
column headers were sometimes eliminated and some of the tables were
rearranged.