[Illustration: A SUB-SURFACE IRRIGATION SEWAGE-DISPOSAL PLANT. _Sewage._ _Frontispiece._ ] Practical Methods of Sewage Disposal FOR RESIDENCES, HOTELS AND INSTITUTIONS BY HENRY N. OGDEN M. AM. SOC. C.E. _Professor of Sanitary Engineering, Cornell University_ AND H. BURDETT CLEVELAND ASSOC. M. AM. SOC. C.E. _Principal Assistant Engineer, New York State Department of Health_ _FIRST EDITION_ _FIRST THOUSAND_ NEW YORK JOHN WILEY & SONS LONDON: CHAPMAN & HALL, LIMITED 1912 Copyright, 1912, by HENRY N. OGDEN and H. BURDETT CLEVELAND PUBLISHERS PRINTING CO., 419–421 LAFAYETTE ST, NEW YORK ------------------------------------------------------------------------ CONTENTS CHAPTER I. INTRODUCTORY PAGES The problem of sewage disposal. Composition and character of 1–13 sewage. Action of bacteria. Soils and their value for sewage treatment. Three essential conditions for effective sewage purification. Rates of operation. Preliminary and final treatment. CHAPTER II. THE SETTLING TANK Function and capacity of settling tanks. Their construction. 14–36 Siphon chambers. Use of concrete. Pipe connections. Roof. Baffle boards. Imhoff or Emscher tanks. CHAPTER III. VALVES, SIPHONS, AND SIPHON CHAMBERS Hand valves. Gate valves. Flap valves. Various types of 37–54 siphons. Alternating and plural siphons. Air-lock siphons. Dosing apparatus. CHAPTER IV. SUB-SURFACE IRRIGATION Advantages of sub-surface irrigation for sewage disposal. 55–72 Details of system. Tables for use in constructing. Siphon chambers. Sub-surface tile. Alternate use of separate portions of area. Underdrainage. CHAPTER V. SEWAGE FILTERS Relative efficiency of various types. Sand Filters. Tables for 73–97 use in constructing siphons. Dosing and distribution methods. Maintenance. Contact Beds. Methods of construction. Alternate and timed siphons for filling and discharging. Table for use in constructing. Sprinkling Filters. Their construction and operation. Complicated and undesirable for small installation. CHAPTER VI. BROAD IRRIGATION