Sewerage and Sewage Treatment

by Harold E. Babbitt

INDEX

• A. B. C. process of sewage treatment, [4]
• Abandonment of contract, [225]
• Access to work, [228], [229]
• Accident, contractor’s responsibility, [221], [224]
• Acetylene, explosive, [347]
• Acid precipitation. See Miles Acid Process.
  • of sludge, [503]
• Acids as disinfectants, [489], [490]
• Activated sludge. Chapter XVIII, [465]–479
  • advantages and disadvantages, [469], [470]
  • aëration tank, [471], [472]
  • air diffusion, [475], [477]
  • air distribution, [473]–478
  • air quantity, [475], [476]
  • area of filtros plates, [478]
  • colloid removal, [358]
  • composition, [465]–469
  • cost, [478], [479]
  • definition, [466]
  • dewatering, [468], [469], [497]–505
  • fertilizing value, [469], [470]
  • historical, [470], [471]
  • how obtained, [478]
  • nitrogen content, [468]
  • patent, [471]
  • process, [465]
  • quantity, [469]
  • reaëration tank, [473]
  • results, [467], [468], [476]
  • sedimentation tank, [472]
• Advertisement, [214]
• Aëration, effect on oxygen dissolved, [373]–375
  • of sewage, [371], [376], [465]–479
• Aërobes, [363]
• Aërobic decomposition, [366], [367]
• Aftergrowths, [492]
• Aggregates, specifications, [172]–174
• Air, see also ventilation, activated sludge, compressed air, etc.
  • ejectors, [150]
  • lock dosing apparatus. Chap. XXI, [506]–512
  • machinery for activated sludge, [473], [474]
• Algæ, [363]
• Alkalinity, [358]
• Alleys, sewers in, [80]
• Alum, [407], [408]
• Alvord tank, [427], [429]
• Ammonia, [366], [367], [374], [375], [410]
  • explosives, [297]
• Analyses, bacteriological, [364]
  • chemical, [354], [355]
  • mechanical of sand, [182]
  • physical, [352]–354
  • sewage, [352]–364
• Anaërobes, [363], [365]–367
• Anaërobic, action, [410]
  • bacteria, [363]
  • conditions, [367]
  • decomposition, [365]–367
• Ann Arbor, Michigan, Population, [14]
• Annual expense, method of financing, [157], [158]
• Ansonia air ejector, [150], [151]
• Antibiosis, definition, [363]
• Appurtenances to sewers. Chap. VI, [99]–115
• Arch, analyses, [204]–208
  • • elastic method, [206]–208
    • vouissoir analysis, [204]–206
  • brick construction, [312], [313]
  • centers for brick sewers, [313]
  • concrete construction, [318]–321
• Ardern and Lockett, development of activated sludge, [467], [468], [471]
• Area of cities, [31]
• Asphyxiation in sewer gas, [336]
• Assessments, special, [15], [16]
• Augers, earth, [21]
• Automatic, regulators, [117]–121
  • siphons, flush-tanks, [110]
    • double alternating, [507]
    • multiple alternating, [508]–512
    • timed, [510]
    • timed and multiple alternating, [510]–512
    • triple alternating, [508]
• Bacillus, definition and morphology, [362], [363]
• Backfilling, [328]–331
• Backfill, puddling, [330]
  • weight of, [199], [201]
• Backwater curve, [73]
• Bacteria, definition and morphology, [362], [363]
  • good and bad, [363], [364]
  • nature of, [362], [363]
  • nitrifying, [431], [432]
  • sanitary significance of, [364]
  • in sewage, [362], [363]
  • total count, [364]
• Bacterial analyses, results in sewage, [364]
• Baffles, scum, [404], [413], [414], [421]
  • • in sedimentation tanks, [404]
    • in septic tanks, [413], [414]
    • in Imhoff tanks, [421]
• Balls, for cleaning sewers, [338]
• Band screen, [384]
• Barring, definition, [263]
• Bars for screens, [390]
• Basins, sedimentation, baffling, [404]
  • bottoms, [404]
  • cleaning arrangements, [404]
  • depth, [401]
  • economical dimensions, [401]–403
  • inlets and outlets, [404]
  • scum boards, [404]
  • types, [395]
• Basket handle sewer section, [67], [69]
• Bathing beaches, pollution, [381]
• Bazin’s formula, [54]
• Bearings, for centrifugal pumps, [131], [137], [138]
  • thrust, [138]
• Bellmouth, [121], [122]
• Bends in pipe, loss of head in, [116]
• Berlin, sewage farm, [460], [461]
  • sewers, date of, [3]
• Bids, proposal, [217]–219
• Bidder’s duties, [215]–217
• Bio-chemical oxygen demand, [359]–361
• Biolysis of sewage, [366], [367]
• Black and Phelps dilution formulas, [377]–379
• Blasting and explosives, [294]–304
  • caps, [297], [299], [300]
  • detonators, [294], [297]–300
  • firing, [302]–304
  • fuses and detonators, [297]–300
  • fuses, delayed action, [291], [300]
  • fuses, electric, [299], [300]
    • splicing, [303]
  • gelatine, [296]
  • loading holes, [303]
  • powder, [295]
  • precautions, [300]–302
  • priming and loading, [303]
  • rock, [269]
  • size of charge, [304], [305]
  • tunneling, [290], [291]
• Bleach, characteristics of for disinfection, [491]
• Block sewer, construction, [311]–314
  • hollow tile as underdrains, [126]
• Blocks, vitrified clay, [189], [190]
• Boilers, steam, [147]–150
• Boilers, efficiencies, [149]
  • horse-power, [149]
• Bond, contractor’s, [213], [214], [232]
  • issues, [14]
• Bonds, definition and types, [14]–16
• Boring underground, [20]
• Bottom, activated sludge aëration tank, [472]
  • Imhoff tanks, [423]
  • sedimentation tanks, [404]
  • trickling filter, [451], [452]
• Box sheeting, [272]
• Branch sewer, defined, [7]
• Breast boards, [288]
• Brick, arch construction, [312], [313]
  • and block sewer construction, [311]–315
  • invert construction, [311], [312]
  • sewer construction, [311]–315
    • arch centers, [313]
    • invert, [311]–312
    • organization, [314], [315]
    • progress, [314]
    • row lock bond, [312]
  • specifications, [188], [189]
  • sewers, life of, [351]
• Bricks for sewers, [316]
• British Royal Commission on Sewage Disposal, [4]
• Broad irrigation. See under Irrigation.
• Bucket excavators, [246], [255], [256]
• Building material, weight of, [201]
• Burkli-Ziegler formula, [47], [425]
• Butyrine, [366]
• Cableway excavators, [246], [250]–252
• Cage screen, [384], [385]
• Caisson excavation, [285], [286]
• Calcium carbide, explosive, [347]
• Calumet pumping station, [128], [142]
• Cameron septic patent, [411]
• Capacity of sewers, diagrams, [57]–60
• Capital, private invested in sewers, [17]
• Capitalization, method of financing, [157]–160
• Caps, blasting. See blasting.
• Carbohydrate, [366], [367]
• Carbon, analysis for, [356]
  • dioxide, [366], [367]
• Carson Trench machine, [250], [251]
• Cast-iron pipe, [122], [164], [190], [191]
  • joints, [164]
  • quality, [101], [102], [190]
• Castings, iron, [101], [102]
• Catch-basins, [99], [107]–108, [217]
  • cleaning, [343], [344]
  • inspection, [337]
• Catenary sewer section, [69]
• Cellars, depth of, [88]
• Cellulose, [367]
• Cement. See also Concrete,
  • pipe, specifications, manufacture and sizes, [171]–179
  • vs. concrete, [164]
• Centrifugal pumps. See pumps, centrifugal.
• Centrifuge for sludge drying, [501], [502]
• Cesspool, [411], [416], [417]
• Champaign, Illinois, septic tank, [415], [416]
• Changes in plan, [222], [223]
• Channeling, definition, [263]
• Character of surface, [44]
• Chemical analyses, [354]–362
• Chemical precipitation, [371], [405]–409
  • chemicals used, [405]–407
  • preparation of chemicals, [407], [408]
  • results, [408], [409]
  • at Worcester, [408]
• Chezy formula, [52], [53]
• Chicago. See also Sanitary District of Chicago.
  • drainage canal, [374], [375]
  • dilution requirement for sewage, [380]
  • early sewers, [3]
  • method of sewage disposal, [374]
  • population and density, [29], [30]
  • trench excavation in, [248]
• Chlorine. See also Disinfection.
  • disinfectant, [489]–493
  • in sewage, [358], [374], [375]
• Chlorine liquid, application, [491], [492]
• Cholera, transmittable disease, [364]
• Chromatin, [365]
• Chutes for concrete, [187]
• Circular sewer section, hydraulic elements, [65], [66], [69]
  • types, [70], [71]
• City, growth of area, [31]
  • growth of population, [24]–28
  • legal powers, [219]
• Clay, life of pipe, [349]–351
  • manufacture of pipe, [165]–167
  • specifications for pipe, [168]–170
  • unglazed for pipe, [165]
  • vitrified blocks, [167], [189], [190]
  • vitrified pipe, [165]–171
• Cleaning, grit chambers, [398], [400]
  • sedimentation basins, [404]
  • sewers, cost, [341]
  • in N. Y. City, [332]
  • methods, [337]–343
  • tools, [338]–340
  • up after completion of work, [228]
• Coccus, [362]
• Coefficient of uniformity of sand, [456]
• Coffin sewer regulator, [117], [118]
• Colloid, nature of, [358]
  • treatment for, [358]
• Color of sewage, [352], [353]
• Combined sewer system, [78], [79]
• Commercial districts, characteristics of and sewage from, [32], [34], [35]
• Compensators for pumps, [142]
• Compressed air. See also ventilation, tunneling, drilling, etc.
  • activated sludge, [473]–475
  • for drilling, [264]–268
  • in tunnels, [292]–294
  • transporting concrete, [320], [321]
• Concentration, time of flood flow, [41]–43, [96], [97]
• Concrete, aggregates, [172]–174
  • mixing and placing, [184]–188
  • pipe, details, [175]–179
    • manufacture, [171]–179
    • reinforcement, [177], [178], [209], [210]
  • pipe, steam process, [176]
    • sizes, [175]
  • pressure against forms, [232], [323]
• Concrete, proportioning, [179]–183
  • qualities, [179], [180]
  • reinforcement, placing, [178], [326], [327]
  • reinforcing steel, quality, [191]
  • sewer construction, [314]–328
    • arch, [318]–321
    • form length, [319]
    • labor costs, [327], [328]
    • in open cut, [314]–320
    • in tunnel, [320], [321]
    • invert, [315]–320
    • organization for, [328]
    • working joints, [319]
  • sewer costs, [327]–329
  • strength, [181]
  • waterproofing, [184]
• Conduits, special sections, [67], [70], [71]
• Connections to sewers, ordinances, [344], [345]
  • record of 92, [238]
• Construction of sewers, Chap. XI, [233]–331
• Construction, elements of, [233]
  • organizations, [315], [328]
• Contact bed, [432]–437, [506]
  • advantages and disadvantages, [432]–434
  • automatic control, [437], [506]
  • cleaning, [435]
  • clogging, [435]
  • construction, [434]–436
  • control, [437], [506]
  • cycle, [436], [437]
  • depth, [434]
  • description, [432], [433]
  • design, [434]–436
  • dimensions, [434], [435]
  • loss of capacity, [435]
  • material, [435], [436]
  • multiple, [433], [435]
  • operating conditions, [432]–437
  • rate, [435]
  • results, [433], [434]
  • ripening, [432]
• Continuous bucket excavators, [246]–250
• Contour interval on maps, [79], [80]
• Contracts, Chap. X, [211]–232
  • abandonment of, [225]
  • assignment, [228]
  • completion of, [222], [228]
  • bond, [213], [222]
  • content, [213], [230], [231]
  • cost-plus, [212], [213]
  • disputes, [220]
  • divisions of, [213]
  • drawings, [213]
  • engineer as an arbitrator, [220]
  • the instrument, [230], [231]
  • interpretation of, [220], [234], [235]
  • lump sum, [212]
  • nature of, [211], [212]
  • sample, [230], [231]
  • time allowed, [222]
  • types, [212], [213]
  • unit-price, [213]
• Contractor, absence of, [222]
  • bond, [232]
  • claims against, [228]
  • duties, [221]
  • liability, [224]
  • relations with other contractors, [228], [229]
• Contractor’s powder, [294]
• Control devices, automatic, for sewers, [117]–121
  • • for filters, [500]–512
  • inspection of, [336], [337]
• Copper sulphate, disinfectant, [490]
• Copperas, precipitant, [406]–408
• Cordeau Bickford, [298], [303]
• Corrugated iron pipe, [165]
• Cost. See under item wanted.
• Cost, annual. Method of financing, [157]–160
  • capitalized. Method of financing, [157]–160
  • classification of, [235]–238
  • comparisons of. Methods for
  • making, [157]–160
  • collection of data, [10]–14, [235]–238
  • estimate. Method of making, [10]–14
  • overhead, [237], [238]
• Couplings, flexible for shafts, [138]
• Covers, Imhoff tanks, [424]
  • septic tanks, [415]
  • trickling filters, [451]
• Crops on sewage farms, [463], [464]
• Cunette, [67], [70]
• Cut, depth of excavation, [88], [92]
• Cycle, contact bed, [436]
  • life and death, [367], [431]
  • nitrogen, [367], [368]
  • trickling filter, [441]
• Cylinders, stresses in, [194], [202]–204
• Cytoplasm, [365]
• Damages, liquidated, [222]
  • material, [221], [224]
• Darcy’s formula, [52]
• Day labor, [211]
• Decomposition of sewage, [365]–367
• Definitions. See word defined.
• Deflagration, definition, [294]
• Delays in contract work, [228]
• Delayed action fuses, [291], [300]
• Densities. See population.
• Depreciation, of sewers, [348]–351
  • rate of, financial, [158]
• Depth of sewers, [88]
• Design conditions, [88]–92
  • economical, mathematics of, [401]–403
  • preparations for, [17]–23
• Detention period, grit chamber, [397]
  • Imhoff tank, [419]
  • plain sedimentation, [392]–395, [401]
  • septic tank, [415]
• Detonation, definition, [294]
• Detonator. See blasting cap.
• Diameter of sewers, [57]–60, [72], [88]–92
• Diaphragm pump, [257], [258]
• Diesel engine, [152], [154]
• Digestion chamber, Imhoff tank, [422], [423]
• Digestion of sludge in separate tank, [427]–430, [497]
• Dilution, amount needed, [377]–380
  • conditions for success, [372], [373]
• Dilution, definition, [372]
  • formulas for quantity, [378]–380
  • governmental control, [380], [381]
  • preliminary studies, [381], [382]
  • in salt water, [376], [377]
  • in streams, [372]–376
  • of sewage, [370] and Chap. XIV, [372]–382
• Diseases, water-borne, [364]
• Disinfection, [489]–493
  • action of, [489]–491
  • bleaching powder, [491]
  • chlorine, liquid, [491]
    • amount of, [492]
  • disinfectants, [489], [490]
  • purpose, [489]
  • selective action of disinfectants, [492], [493]
• Disk screen, [384]
• Disposal of sewage, See sewage treatment.
• Disputes, engineer to settle, [220]
• Dissolved oxygen. See Oxygen dissolved.
• Distribution of sewage,
  • contact beds, [436]
  • irrigation, [461], [462]
  • nozzles, [442]–449
  • sand filter, [450]–458
  • traveling distributor, [442]
  • trickling filters, [441]–451
• Districts, character of, [29], [30], [32]–37
  • classification of, [34], [35]
• Domestic sewage, defined, [6], [7], [352]
• Dorr Thickeners, [472], [504]
• Dortmund tank, [404]
• Dosing devices, [506]–512
  • alternating and timed siphons, [500]–512
  • Alvord device at Lake Forest, [506]
  • four or more alternating siphons, [509]
  • operation of automatic siphon, [110]
  • three alternating siphons, [508]
  • timed siphons, [510]
  • two alternating siphons, [507]
    • types, [506]
• Dosing tank design, for trickling
  • filter, [446]–450
• Doten tank, [429], [430]
• Drag line excavators, [255], [256]
• Drainage areas, [81], [84], [94]
• Drills, electric, [267]
  • jack hammer, [264], [265]
  • punch, [20]
  • size of cylinder for, [266]
  • tripod, [264], [265]
• Drilling, methods, [20]–23, [264]–270
  • depth, diameter and spacing of
  • holes, [268]–270
  • power for, [267], [268]
  • rate of, in rock, [267]
  • steam and air, [267], [268]
• Drop manhole, [100], [101]
• Drop-down curve, [73], [77]
• Drum screen, [384]
• Dry weather flow, [24], [38]
• Drying sludge. See sludge drying.
• Dualin, [296]
• Duty of contractor. See Contractor, duties
• Duty of engineer. See Engineer, duties.
• Duty of inspector. See Inspector, duties.
• Duty of a pump, defined, [135]
• Dynamite, [296]–298, [300]–302, [304], [305]
  • cartridge, [268], [296], [302]
  • thawing, [301], [302]
• Dysentery, [365]
• Earth pressures, theories, [274], [275]
• Economical dimensions, mathematics of, [401]–403
• Effective size of sand, defined, [456]
• Efficiency of a pump, defined, [135]
• Effluents, character of
  • activated sludge, [467], [468]
  • chemical precipitation, [408]
  • contact bed, [434]
  • Imhoff tank, [414], [424], [425], [432]
  • lime and electricity, [489]
  • Miles acid process, [484], [485]
  • sand filter, [453]
• Effluents, sedimentation tank, [401]
  • septic tank, [412]–414
• Egg-shaped section, [67], [68], [70]
• Ejectors, air, [150], [151]
• Elastic arch analysis, [206]–208
• Electric motors, [150]–152
• Electrolytic treatment, [487]–489
• Elevations, method of recording, [92]
• Emergencies, duties of engineer, [235]
• Emerson pump, [261]
• Engines, internal combustion, [152]–154
  • steam, types, [142]–144.
• Engineer, absence of, [221]
  • defined, [220]
  • disputes settled by, [220], [234]
  • duties of, [9], [10], [220], [233], [234], [238]
  • individuality and personality, [9], [234]
  • qualifications, [9]
  • sanitary, definition, [2]
• Engineering News pile formula, [125], [126]
• Entering sewers, precautions, [335], [336]
• Enzymes, [365]
• Equipment for construction, [237]
• Equivalent sections, defined, [72]
  • solution of problems in, [67]–72
• Estimates, cost and work done, [10]–14
  • when made, [226]
  • data for, [235]
• Excavation, depth of open cut, [284]
  • drainage, [252], [262]
  • hand, [242]–245, [249]
    • economy, [245]
    • laborer’s ability, [243]
    • lay out of tasks, [243]
• Excavation, hand, opening trench, [243]
  • • vs. machine, [245], [249]
    • tools, [242]
  • machine, [244]–246
    • economy, [245]
    • limitations, [246]
    • vs. hand, [245], [249]
  • specifications, [240], [241]
• Excavating machines, bucket, [246], [255]
  • cableway and trestle, [246], [250]–252
  • Carson machine, [250], [251]
  • continuous belt, [246]
    • bucket, [246], [247]
  • drag line, [255]
  • Potter machine, [251]
  • steam shovel, [252]–254
  • tower cableway, [252]
  • wheel excavators, [246]–250
• Excavation, machine, organization, [249]
  • pumping and drainage, [256], [257]
  • quicksand, [256]
  • rock, [263], [264]
    • payment for, [230]
  • specifications, [240], [241]
  • trench bottom, [241], [304], [311]
• Explosions in sewers, [108], [336], [346]–348
  • causes of, [346]
  • historical, [346]
  • prevention, [108], [348]
• Explosives. See also Blasting.
• Explosives, and blasting, [294]–304
  • ammonia compounds, [297]
  • blasting gelatine, [296]
  • contractor’s powder, [294]
  • deflagrating, [294]
  • detonating, [294]
  • detonators, [294], [297]–300
  • “Don’ts,” [300], [301]
  • dynamite, [296]–298, [300]–302, [304], [305]
  • fuses and detonators, [297]–300
  • gelatine dynamite, [296]
  • gunpowder, [295]
  • handling, [300]–302
  • nitro-glycerine, [295]
  • nitro-substitution compounds, [295]
  • permissible, [297]
  • quantity, [304], [305]
  • requirements, [294]
  • strength of, [297], [298]
  • T.N.T., [295]
  • types, [294]–297
• Exponential formulas for flow of water, [54], [55]
• Extra work, compensation, [227]
• Facultative bacteria, [363]
• Fanning’s run-off formula, [49]
• Farms, septic tanks for, [416], [417]
• Farming with sewage. See irrigation.
• Fats in sewage, [357]–359, [366], [367]
  • from Miles acid process, [485]–487
• Feathers, for splitting rock, [264]
• Ferrous sulphate, precipitant, [406]–408
• Fertilizer from sludge, [470], [495], [497]
• Fertilizing value of, activated sludge, [470]
  • sewage, [459], [460]
• Filter press for sludge, [500], [501]
• Filters. See under name of filter.
• Filtration, of sewage, [370], [371], [431]–459
  • action in, theory of, [431]
  • cost, [458], [459]
• Filtros plates, [477], [478]
• Finances, mathematics of, [157]–160
• Financing, methods of, [14]–17
• Flamant’s formula, [54], [56]
• Flies on trickling filters, [438]
• Flight sewer, [101], [102]
• Flood, crest velocities, [42], [43]
  • flow computations, [94]–98
    • McMath formula, [94], [96], [97]
    • Rational method, [95]–98
• Flow, laws of, [52]
  • velocity of, [52], [90], [91]
• Fluctuations, in rate of sewage flow, [33]–38
  • in quality of sewage, [368]–370
• Flush-tanks, automatic, [109]–113
  • capacity, [111]
  • details, [110], [112]
  • inspection of, [336], [337]
  • payment for, [217]
  • siphon sizes, [111]
• Flushing, [109]–113, [341]–343
  • amount of water needed, [112]
  • methods, [341]–343
  • manhole, [109]
  • sewer, defined, [8]
• Foaming of Imhoff tanks, [425], [426]
• Foot valves, [141]
• Force main, defined, [8]
• Forms, design of, [322], [323]
  • length of, [319]
  • materials, [321], [322]
  • oiling, [174], [186], [322]
  • specifications, [322]
  • steel, [325], [326]
  • steel-lined, [325]
  • support for, [316], [318]
  • time in place, [319]
  • wooden, [323], [324]
• Formulas, hydraulic, methods for solution, [55]–61
  • for flow of water, [52]–55
  • for rainfall. See Rainfall,
  • for run-off. See Run-off.
• Foundations, [99], [124]–126
• Franchises for sewers, [17]
• Free ammonia, [366], [367], [374], [375], [410]
• Freezing, catch-basins, [108]
  • concrete, [186], [187]
  • dynamite, [301], [302]
• Fresh sewage, characteristics, [352]–354
• Friction losses. See Head losses.
  • flow in pipe, [51], [52]
• Fuel, consumption by prime movers, [153]
  • costs, [153]
  • heat value, [150]
• Fungus growth in sewers, [333]
• Fuses. See blasting fuses.
• Ganguillet and Kutter’s formula, [52]–65
• Gas, chamber in Imhoff tank. See Scum chamber.
  • engines, [152]–154
  • illuminating, explosive, [347]
  • sewer, [335], [336]
• Gasoline, explosive, [108], [109], [335], [346], [347]
  • engines, [152]–154
  • and oil separator, [109]
  • odors, significance, [335], [353]
• Gearing, reduction for turbines, [140], [146]
• Gelatine dynamite, [296]
• Glycerol, [366]
• Gothic section, [67]
• Governmental control, stream pollution, [380], [381]
• Grade, of sewers. See also Slope.
  • how given, [281]–284
  • selection of, [90]
  • stakes, [221], [281]–283
• Gravel, specifications, [172]
• Grease, in sewers, [99], [108], [333], [345]
  • cutter, [340]
  • ordinance concerning, [345]
  • traps, [99], [108]
• Gregory’s imperviousness formulas, [44], [46]
• Grit, clogs sewers, [333]
  • chambers, [127], [397]–401
    • description, [395], [398]
    • design, [397], [398]
    • dimensions, [397], [398]
    • existing, [398]–400
    • outlet arrangements, [400]
    • results, [397]
    • retention period, [397]
    • sludge analyses, [397]
    • units, number of, [400], [401]
    • velocity of flow in, [396]–398
  • quantity and character of, [397]
• Grooves in concrete, working joints, [319]
• Ground water in sewers, [38], [39], [85], [87], [256], [352]
• Gun cotton, [296]
• Gunpowder, [295]
• Hazen, theory of sedimentation, [392]–395
  • dilution formula, [380]
• Hazen and William’s formula, [55], [57]
• Head loss, in bends, [116]
  • entrance, [115]
  • friction in straight pipe, [51], [52], [115]
• Hercules powder, [296]
• Hering, Rudolph, dilution recommendations, [380]
• Hering, Rudolph, introduction of Imhoff tank and hydraulic formulas, [425]
• Historical résumé of sewerage and sewage treatment, [2]–5
• Hitch, tunnel frame, [286], [287]
• Holes, drill. See Drill holes.
• Holidays, work on, [221]
• Hook for lifting pipe, [304], [306]
• Horse-power, boiler, [149], [150]
  • of pumps, [144]–146
• Horseshoe sewer section, [71]
• House, connections, record of, [92], [234]
  • drains, [7], [88], [90]
  • sewer, defined, [7]
• Hydraulic, elements, [65], [69]
  • formulas, [52]–55
  • jump, [73]–74
  • principles, [51], [52], [72], [73]
  • value of settling particles, [393]
• Hydraulics of, sewers, Chap. IV, [51]–77
  • circular pipes partly full, [65], [66]
  • equivalent sections, [72]
  • non-uniform flow, [72]–77
  • sections other than circular, [67]–72
  • use of diagrams, [61]–65
• Hydrocarbon, [367]
• Hydrogen sulphide, [353], [366], [410]
• Hydrolytic tank, [427], [428]
• “Hypo” as a disinfectant, [491]
• Hytor Turbo blower, [473], [474]
• Illinois River, self-purification, [374]–376
• Imhoff tank, and chlorination, costs, [487]
  • cover, [424]
  • description, [417]–419
  • design, [419]–424
  • digestion chamber, [422]
  • inlet and outlet, [421]
  • operation, [426]–427
  • patent, [418]
  • results, [414], [424], [425], [439], [467]
  • sedimentation chamber, [419]–422
  • scum chamber, [424]
  • slot, [422]
  • sludge, [414], [467]
  • sludge pipe, [423], [424]
  • status, [425], [426]
  • and trickling filter, cost, [479]
• Impeller, for centrifugal pump, [131], [136]
• Imperviousness, relative, [40], [42], [44]–46, [95]–97
• Industrial, districts, [32]–37
  • wastes, defined, [7], [352]
  • tannery, [491]
• Information and instructions for bidders, [213], [215]–217
• Inlets, street, [93], [94], [99], [104]–107
• Inspection, contract stipulations, [221]–224
  • during construction, [233], [234]
  • for maintenance, [104], [333]–337, [348], [349]
• Inspector, absence of, [221], [222]
  • duties, [233]–234
  • qualifications, [234]
• Institutional sewage treatment plants, [416], [417]
• Intercepting sewer, defined, [7]
• Intermittentsand filter. See Sand filter.
• Internal combustion engines, [152]–154
• Inverted siphon, [113]–116
• Iron, ferrous sulphate, precipitant, [406]–408
  • cast. See cast iron.
• Irrigation. See also Farming and Sewage farming.
  • area required, [463]
  • Berlin sewage farm, [460], [461]
  • crops, [463], [464]
  • description, [459]
  • fertilizing value of sewage, [460], [470], [495], [498]
  • vs. farming, [459]
  • operation, [461]–463
  • preliminary treatment, [462], [463]
  • preparation for, [461]–463
  • process, [459], [460]
  • sanitary aspects 463
  • status, [460], [461]
  • theory, [432]
  • in the United States, [461]
• Jack hammer drill, [264], [265]
• Jetting method, [21]–23
• Jet pump, [259], [341], [343]
• Joints, bituminous, [309]–311
  • in cast-iron pipe, [164]
  • cement, [307], [308]
  • inspection of, [234]
  • lead, [164]
  • mortar, [307]
  • open, [307]
  • poured, [309]–311
  • cement, [309], [311]
  • riveted steel, [195], [196]
  • sulphur and sand, [309]
  • types, for pipe, [307]
  • working, in concrete, [319]
• Junctions, [99]
• Kuichling, run-off rules, [46], [47], [49]
  • storm intensity formulas, [50]
• Kutter’s formula, [52]–65
• Labor, day vs. contract, [211]
  • costs on concrete sewer, [328], [329]
• Labyrinth packing rings, [136], [137]
• Lagging, tunnel frames, [287]
  • for forms, [322]
• Lagooning sludge, [495]–497
• Laitance, [186], [188]
• Lakes, self-purification of, [376]
• Lampé’s formula, [54]
• Lampholes, [99], [104]
• Lateral sewer, defined, [7]
• Lawrence Experiment Station, [4]
• Leaping weir, [118]–121, [337]
• Legal requirements, construction, [224]
  • dilution, [380], [381]
  • in design, [9]
• Liernur system, [5]
• Life, organic in sewage, [363], [364]
  • of sewers, [348]–351
• Lime as a precipitant, [405]–408
  • with electricity, [488], [489]
  • with iron, [406], [407]
• Line and grade, [281]–284
  • how given, [281]–283
• Liquefaction of sludge, [411]–413, [496], [497]
• Liquid chlorine. See also Chlorine, [491]
• Liquidated damages, [222]
• Loads on, pipe, [198]–202
  • Marston’s method, [198]–202
  • trench, [199]–202
• Lock bar pipe, [197]
• Lock-joint pipe, [177]
• Long loads, [201]
• Machine excavation. See Excavation.
• Macroscopic organisms, [363], [368]
• Main sewer, defined, [7]
• Maintenance of sewers, Chap. XII, [332]–351
  • catch-basin cleaning, [343], [344]
  • cleaning sewers, [337]–343
  • complaints, [333]
  • cost, [341]
  • entering sewers, [335], [336]
  • flushing, [109]–113, [341]–343
  • hand cleaning, [341]
  • inspection, [333]–337
  • organization, [332]
  • protection of sewers, [344], [345]
  • repairs, [337]
  • tools, [338]–341
  • troubles, [333]
  • work involved, [332]
• Man, shoveling ability, [243]
• Manholes, [81], [99]–104
  • bottom, [100]
  • cover, [102]–103
  • drop, [101]
  • flushing, [109], [342]
  • location and numbering, [81]
  • payment methods, [217], [218]
  • steps, [100], [103], [104]
• Manning’s formula, [55]
• Map, preliminary, [17], [79], [80], [82], [83]
• Marsh gas, [347], [366], [367], [410], [415]
• Marston’s methods for external loads on buried pipe, [198]–202
• Materials, for sewers, Chap. VIII, [164]–193
  • measurement of, [236], [237]
  • record of, [237]
  • unit weights, [201], [202]
• McMath’s formula, [47], [48], [94], [95]
• Meem’s theory of earth pressure, [274], [275]
• Mercaptan, [367]
• Metabolism, [365]
• Methane, [347], [366], [367], [410], [415]
• Methylene blue, [360]
• Microscopic organisms, [363], [364], [368]
• Miles acid process, costs, [487]
  • amount of acid, [483]
  • analyses of sludge, [485]
  • description, [482]
  • results, [483]–487
  • sludge, [485]
• Mineral matter in sewage, [357]
• Mirror, inspecting device, [334]
• Money retained by city, [227]
• Mosquitoes in catch-basins, [108]
• Motors, electric, [150]–152
• Municipal, bond, [14], [15]
  • corporations, [15]
• n, value of in Kutter’s formula, [53]
• New York City, density of population, [29], [31]
  • siphons under subway, [114]
  • grease and gasoline trap, [108], [109]
  • aëration of sewage, [377], [470]
  • cleaning sewers, [332]
  • depreciation of sewers, [348]–351
• Needle beam, [286], [287]
• Night, soil, [5]
  • work, [221]
• Nitrates, [355], [356]
• Nitrites, [355], [356]
• Nitrifying organisms, [431], [432]
• Nitrobacter, [431], [432]
• Nitro explosives, [295], [296]
• Nitrogen, cycle, [367], [368]
• organic, [355], [356]
• Nitro-glycerine, [295]
• Nitrosomonas, [431], [432]
• Nomograph, [55], [56]
• Non-uniform flow, [72]–77
• Nozzles. See also Trickling filters.
  • coefficients of discharge, [446]
  • types, [445]
• Numbering, drainage areas, [81], [94]
  • manholes, [81]
• Nye steam pump, [260], [263]
• Obstructions to construction, [235]
• Odor of sewage, [353]
• Oil in sewage, [108], [344]–348
• Oiling forms, [174], [186], [322]
• Olein, [366]
• Ordinances, for protection of sewers, [344], [345]
• Organisms in sewage, [363], [364], [368]
• Organic matter, composition, [366]
• Organizations for construction, [315], [317], [328]
• Orders, to whom given, [222]
• Outfall sewer, defined, [8]
• Outlets, [99], [122]–124, [373]
• Overflow weir, [118]–121
  • inspection of, [337]
• Overhead, costs, division of, [10], [237], [238]
  • -track excavators, [246], [250], [251]
• Oxidation in streams, [373]–376
• Oxygen, absorption of, [374]–377
  • consumed, [355], [356]
  • demand, [359]–361
  • computation of, [360]
  • bio-chemical, [359]–361
• Oxygen dissolved
  • exhaustion of, [366]
  • in dilution, [381]
  • solubility, [362]
  • supersaturation, [361]
  • concentration for successful dilution, [377]–380
  • formulas for concentration, [378]–380
  • significance of in sewage, [359]–362
• Oysters, contamination of, [372], [489]
• Packing rings, labyrinth type, [136], [137]
• Palmatin, [366]
• Parasites, [365]
• Paris sewage farm, [460]
• Patents. Protection of City by contractor, [224], [225]
• Pathogenic bacteria, [364]
• Pavement, replacing, [329]
• Payment, final on contract, [228]
• Payments, methods of making, [217], [218]
• Periscope inspecting device, [334], [335]
• Permissible explosives, [297]
• Phenolphthalein indicator, [408]
• Photographic records, [238]
• Piles for foundations, [123]–126
• Pills for cleaning sewers, [338]
• Pipe, bedding, [230], [304], [328]
  • cast-iron. See under cast-iron pipe.
  • design of ring, Chap. IX, [194]–210
  • external loads on, [198]–202
  • joints. See Joints.
  • sewer construction, [304]–311
  • laying, line and grade, [282]–284
  • organization, [311]
  • method of laying, [304], [306], [307]
  • steel, design, [195]–197
  • stresses in, external forces, [194], [202]–204
  • stresses due to internal pressure, [194]
  • stresses in buried pipe, [198]–204
  • stresses in circular ring, [202]–204
  • wood design, [197], [198]
• Plankton, defined, [363]
  • in sewage, [368]
• Plans, changes in contract, [222], [223]
• Plug and feathers for splitting rock, [264]
• Pneumatic, collection system, [5]
  • concreting, [320], [321]
• Poling boards, in open cut, [271], [272]
  • in tunnel, [287]
• Pollution, legal features, [380], [381]
• Population, density, [28]–31
  • predictions, [24]–27
  • served by sewers in the U. S., [3]
  • sources of information, [27], [28]
  • and quantity of sewage, [31], [32]
• Potter trench machine, [251]
• Powder. See Blasting.
• Power pump, [132], [133]
• Precautions in entering sewers, [335], [336]
• Precipitants, chemical, [405]–407
• Preliminary, map, [17], [79], [80], [82], [83]
  • work, [9], [17]–23
• Present worth, [158], [160]
• Pressing sludge, [500], [501]
• Priming explosives, [302]–304
• Private, capital, [17]
  • sewers, [17]
• Privy, [5]
• Profile, for brick sewers, [312]
  • sewer, [92]
  • surface, [88]
• Progress, rate of, [222]
  • reports, [238]
• Promotion (inception of sewers), [9]
• Proportioning concrete. See Concrete proportioning.
• Proposal (contract), [213], [217]–219
• Protection of sewers (ordinances), [344], [345]
• Protein, [366]
• Puddling, backfill, [330]
• Pulsometer pump, [260], [261]
• Pumping, in excavations, [256]–263
  • selection of machinery, [154]–156
  • equipment, cost comparison, [162]
  • station, [128], [142]
    • costs, [156]–163
    • equipment, [127], [128]
• Pumps, air ejector, [150], [151]
  • capacity, [129], [160]–163
  • capacity of units, [160]–163
  • centrifugal, details, [130], [131], [136]–138
    • automatic control, [141], [142]
    • characteristics, [138]–140
    • efficiency, [140]
    • for excavation, [262]
    • motors for driving, [150]–152
    • performance, [138]–140
    • protection of, by screens, [386]
    • selection of, [154]–156
    • setting, [140]–142
    • turbine, [130]–132, [154]
    • types, [130], [131]
• Pumps, centrifugal, volute, [130]–132, [154]
  • character of load, [129]
  • costs, [156], [157]
  • description of types, [130]–134
  • for construction work, [256]–263
  • diaphragm, [257], [258]
  • direct-acting, [133]
  • duty of, [135], [136]
  • efficiencies, [135], [136]
  • ejector, [134], [150], [151], [259], [341], [343]
  • jet, [259]
  • need for, [127]
  • number of units, [160]–163
  • packing of, [133], [134]
  • piston, [133]
    • speed, [133], [134]
  • plunger, [133]
  • power, [132], [133]
  • reciprocating, [130], [132]–135, [154]–156
    • for excavation, [262]
  • reliability, [127]
  • sizes, [135]
  • steam, [134], [135], [142]–146
    • consumption, [144], [145]
    • vacuum, [259], [262]
  • improvised for trench work, [257]
  • turbine, [130]–132, [154]
  • volute, [130]–132, [154]
• Putrescibility, [359], [360]
• Quantity, of sewage, [24]–50, [84]–87
  • variations, [33]–38
  • storm water, [40]–50, [94]–98
• Quicksand, definition, [256]
  • excavation in, [256]
  • safeguards, [235]
• Quiescent water, self-purification, [374]
• Racks. See Screens.
• Rainfall, [17], [40], [41], [50], [96], [97]
  • data, [17]
  • rate, [96], [97]
• Rangers, [270]–274, [276]–279
• Rankine’s theory of earth pressure, [275]
• Rapid sand filtration of sewage, [458]
• Rational method of run-off determination, [40], [95]–98
• Reaëration tank in activated sludge, [473]
• Receiving well, capacity, [129], [130]
• Reciprocating pumps. See Pumps, reciprocating.
• Records, character of, on construction, [238]–240
• Rectangular sewer section, [67]–69
• Regulators, [99], [117]–121, [337]
  • inspection of, [337]
• Reinforced concrete sewer design, [209], [210]
• Reinforcing steel, specifications, [191]
  • placing, [326], [327]
• Reinsch Wurl screen, [384]
• Relative stability numbers, [359]
• Relief sewer, defined, [7]
• Repairs to sewers, [337]
• Report, engineer’s preliminary, [10]
• Reservoir, collecting capacity, [129], [130]
• Residences, septic tanks for, [416], [417]
• Residential districts, characteristics, [32]–37
• Residue on evaporation, [356], [357]
• Rideal’s dilution formula, [379]
• Ring, design. Chap. IX, [194]–210
  • stresses in circular, [202]–204
• River pollution, legal features, [380], [381]
• Rivers, self-purification of, [373]–376
• Riveted joints, properties, [196]
• Rock, blasting, [268], [290], [291]
  • definition, [263]
  • drill, data on, [266], [267]
  • drilling. See also Drilling.
    • by hand, [264]
    • by power, [264]–268
    • rates, [267]
  • excavation. See also Excavation.
    • payment for, [230]
  • measurement of, in place, [235]
  • tunnels, [290], [291]
• Rods, sewer, [338]
• Roman ordinance relative to sewers, [2]
• Roofs. See Covers.
• Root cutters, [340]
• Roots, [333], [340]
• Row lock bond for bricks, [312]
• Running water, self-purification, [373]–376
• Run-off, computations, [17], [40], [46]–50, [94]–98
• Safeguards during construction, [221], [241]
• Salt water, dilution in, [376], [377]
• Sand, effective size, [456]
  • uniformity coefficient, [456]
  • filters, [452]–459
    • action in, [431], [432], [452]–454
    • control, [458], [506]–510
    • description, [452]
    • dimensions, [456]
    • distribution systems, [433], [456]–458
    • dosing, [454]–456
    • dosing devices, [506]–510
    • materials, [456]
    • operation, [454], [455]
    • preliminary treatment, [455]
    • rate, [455]
    • results, [452], [453]
    • size of sand for, [456]
    • thickness, [456]
    • in winter, [455]
• Sanitary District of Chicago,
  • dilution factor, [380]
  • specifications, for manhole covers, [101], [102]
  • tunnel cover, [284]
  • tunnel ventilation, [291]
• Sanitary engineering, [1], [2]
• Sanitary sewage, defined, [7], [352]
• Saph and Schoder’s formula, [54]
• Saprophytes, [365]
• Screed, [316]
• Screens, [383]–391
  • chlorination and fine screens, costs, [487]
  • coarse, [386], [391]
  • data on fine, [388], [389]
  • design of, [389]–391
  • fine, [381], [382], [387]–389
  • fixed, [385], [390]
  • medium, [386]
  • movable, [385], [386], [389]–391
  • moving, [384]–386
  • openings, [386]–389
  • protection to pumps, [127], [141]
  • purpose, [383]
  • results, [386]–389
  • sewage treatment by, [371], [381]
  • size and performance, [386]–389
  • sizes, [386]–391
  • types, [384]–386
• Screening, vs. sedimentation, [383]
  • purpose, object, [383]
• Screenings, character of, [386]–389
• Scum, boards for, septic tanks, [413], [414]
  • • Imhoff tanks, [421]
  • chamber in an Imhoff tank, [424]
  • definition, [495]
• Sediment, velocity of transportation, [396], [397]
• Sedimentation, [383]–405
  • definition, [383]
  • Hazen’s analysis, [392]–395
  • hydraulic values, [393]
  • a method of treatment, [370]
  • object, [383]
  • Peoria Lakes, [376]
  • protection of siphons, [113], [114]
  • results from plain sedimentation, 401
  • theory of, [391]–395
  • transportation of debris, [396]
  • velocity of, [392], [393]
  • vs. screening, [383]
  • velocities, limiting, [396], [397]
• Sedimentation, basins, arrangement, [394]
  • baffling, [404]
  • cleaning, [404]
  • dimensions, [401]–403
  • inlet and outlet, [404]
  • operation, [411]
  • types, [395]
  • chamber, Imhoff tank, [419]–422
• Self-purification of lakes, [376]
• Self-purification of streams, [373]–376
• Separate sewer systems, [78]–80
• Septic action, [353], [365]–368, [371], [410], [411], [496], [497]
  • results, [412], [413]
  • vs. sedimentation, [411]
• Septic tank, [411]
  • baffling, [413], [414]
  • capacities of small tanks, [417]
  • for country homes, [416], [417]
  • covers for, [415]
  • definition, [411]
  • design, [413]–417
  • explosions in, [415]
  • results, [412], [413]
  • seeding, [413]
  • sludge storage, [414]
  • small, [416], [417]
  • units, [415]
• Septic sludge analysis, [414]
• Septicization. Chap. XVI, [410]–430
  • a method of treatment, [371]
  • the process, [410], [411]
  • results, [412], [413]
• Settling solids, [357]
• Sewage and water supply, [32]
  • aëration, [371], [376], [465]–479
  • alkalinity of, [358]
  • analyses, chemical, [355], [369], [467]
    • interpretation of, [356]–362
    • physical, [352]–354
  • average, [352]–355
  • bacteria, [362]–365
  • biolysis of, [366], [367]
  • changes in, rate of discharge of, [33]–38
    • characteristics, [368]–370
  • characteristics of, [352]–354
  • chemical constituents, [354]–356
  • classification of, [6], [7], [352]
  • collection, [5]
  • color, [352], [353]
  • components and properties, [352]–356
  • decomposition of, [365]–367
  • definition, [6], [7], [352]
  • disposal. See also Sewage treatment.
  • methods, [6], [370], [371]
    • purposes, [370], [371]
  • domestic, [7], [352]
  • farming. See Irrigation.
  • fertilizing value, [459], [460]
  • flow fluctuations, [33]–38
    • ratio of maximum to average, [36], [37], [85]
  • fresh, [352]–354
  • gas, [335], [336], [353]
  • industrial, defined, [7], [352]
  • life in, [363]–365, [368]
  • odor, [353]
  • physical, analyses, [352]–354
    • characteristics, [352]–354
  • quality variations, [368]–370
  • quantity. Chap. III, [24]–50, and [84], [87]
    • and population, [31], [32]
    • of sanitary, [24]–40
    • variations, [33]–38
  • sanitary, defined, [7], [352]
  • septic, [353], [365]–368, [371], [410], [411], [496], [497]
  • stability, [359], [360]
  • stale, [353]
  • storm, defined, [7], [352]
  • strong, [355]
  • temperature, [353]
  • turbidity, [353]
  • treatment processes, [370], [371]
    • A. B. C., [4]
    • activated sludge, Chap. XVIII, [465]–479
    • biological, [371]
    • chemical, [371]
    • contact bed, [432]–437, [506]
    • costs, [459]
    • dilution. Chap. XIV, [372]–382
    • disinfection, [489]–493
    • electrolytic, [487]–489
    • filtration, [431]–459
    • increase of, [3]
    • irrigation, [431], [459]–464
    • mechanical, [471]
    • Miles acid process, [482]–487
    • purpose of, [6], [370]
    • résumé, [6], [370], [371]
    • sand filter, [452]–458
    • screening, [383]–391
    • sedimentation, [391]–409, [411]
    • septicization. Chap. XVI, [410]–430
    • trickling filters, [437]–452
  • weak, [355]
  • and water supplies, [31], [32]
• Sewerage, definition, [7]
  • demand for, [2]
  • design, [78]–98
  • growth of, [2]–4
  • historical, [2]–4
• Sewers, ancient, [2], [3]
  • capacity, diagrams, [56]–60
  • cost, [10]–14
  • definitions of various types, [7], [8]
  • depth of, [88]
  • diameter, [58]–60, [88]–92
  • flat grades, [73], [109]
  • flight, [101], [102]
  • inspection of, [333]–337
  • life of, [348]–351
  • location of, [80], [81], [94]
  • materials. Chap. VIII, [164]–193
  • medieval, [3]
  • pipe, properties of concrete, [175]
    • design. Chap. IX, [194]–210
    • vitrified clay, properties, [169]–171
  • profile, [89], [92]
  • section of different types, [67]–72
  • separate system, [78], [79], [82], [86], [87]
  • slope, [88]–92
  • storm-water system, [78], [79], [83], [93], [94]
  • stresses in, [194], [198]–204
• Shafts, for tunnels, [284]–287
• Sheeting, [270]–280
  • alignment, [240], [241]
  • backfilling, [330]
  • box, [272]
  • design, [275]–280
  • driving, [273]
  • length, [273]
  • lumber, [277]
  • moving, [248]
  • poling boards, [271], [272], [287]
  • pulling, [274]
  • skeleton, [270], [271]
  • stay bracing, [270]
  • steel, [252], [280], [281]
  • thickness, [276]–278
  • types, [270]
  • vertical, [270], [272]–274
  • Wakefield piling, [273]
• Shellfish contamination, [372], [489]
• Shields, tunnel, [288]–290
• Short loads on trenches, [202]
• Shovels, for hand excavation, [242]
  • steam. See Steam shovels.
• Shovel vane screen, [384]
• Shoveling by hand, height raised, [244]
  • performance by one man, [243]
• Symbiosis, definition, [363]
  • example, [432]
• Sinking fund, [158]
• Siphons, automatic. Chap. XXI, [506]–512. See also under Dosing devices.
  • in flush-tanks, [109]–110
  • inspection, [337]
  • operation, [109]–110, [506]–512
  • for trickling filter, [448]–451
  • true and inverted, [113]–117
• Skeleton sheeting, [270], [271]
• Slope, of sewers, [88]–92
  • of tank bottoms, Imhoff, [419], [423]
    • sedimentation tank, [404]
• Skewback, [204]
• Sludge. Chap. XX, [495]–505
  • activated. Chap. XVIII, [465]–479. See also under Activated sludge.
  • analyses, [414], [467], [468], [485], [496]
  • characteristics, [495]
  • definition, [495]
  • digestion tanks, [427]–430, [497]
  • disposal methods, [495]
  • drying, [497]–505
    • acid flotation, [503]
    • beds, [498], [500]
    • centrifuge, [501]–502
    • heat, [502], [503]
    • press, [500]–501
    • thickeners, [504], [505]
  • fertilizing value, [470], [495], [497]
• Sludge, filters, [498]–500
  • lagooning, [495], [496]
  • measurement, [427]
  • press, [500], [501]
  • sedimentation, [401]
  • septic analysis, [434]
  • treatment methods, [495]
• Soaps, [357]
• Soil, bearing value, [125]
  • stack, definition, [7]
• Solids in sewage, [356]–368
• Special assessment, [15], [16]
• Specifications. Chap. X, [211]–232
  • general, [219]–229
  • special, [230]
  • technical, [229], [230]
• Spiling. See Piles.
• Spirillum, [362]
• Spores, [363]
• Springing line, [204]
• Sprinkling filter. See Trickling filter
• Square sewer section, [68], [69]
• Stability, relative, [359]–361
• Stagnant water, [374]
• Stakes, contractor to provide, [221]
  • where driven, [281], [282]
• Stationing, [92]
• Stay bracing, [270]
• Steam boilers, [147]–150
• Steam, consumption by, pumps, [144], [145]
  • turbines, [144], [147]
  • engines, [144], [145]
  • pumping engines, [142]–146
  • pumps. See Pumps, steam.
  • shovels, [246], [252]–254
  • turbines, [146], [147]
• Stearin, [366]
• Steel, forms. See Forms, steel.
  • pipe, [164], [191], [192]
    • design, [195]–197
    • specifications, [191]
  • reinforcement for concrete, [191], [326]–327
  • sheet piling, [252], [280], [281]
• Stench, historic in London, [4]
• Sterilization. See Disinfection.
• Storm, sewage, definition, [7], [352]
• Storm, sewer system design, [93]–98
  • water, quantity, [40]–50
• Storms, extent and intensity, [50]
• Stream pollution, regulation, [380], [381]
• Streams, self-purification, [373]–376
• Street, inlet. See Inlets.
  • wash, definition, [352]
• Stresses, in buried pipe, [198]–204
  • in circular ring, [194], [202]–204
• Sub-main, defined, [7]
• Subsurface surveys, [18]–20
• Suction for centrifugal pump, [141]
• Sulphur and sand joint compound, [309]
• Sunday work, [221]
• Surface, elevation, [92]
  • of ground, character, [44]–46
  • profile, [88]
  • water, [7], [352]
• Surveys, underground, [18]–20
• Suspended matter, [357]
• Talbot’s run-off formula, [49]
• Tamping, backfilling, [328]–331
• Tannery wastes, disinfection, [491]
• Taxation, general, [16], [17]
• Taylor nozzles, [444], [445]
• Temperature of sewage, [353]
• Templates, brick sewers, [312]
• Thawing dynamite, [301], [302]
• Tide gate, [122]
• Timbering tunnels, [286]–288
• Timber, strength of, [277]
• Time of concentration, [41]–43, [95]–97
• Tools, for cleaning sewers, [337]–341
  • excavating, [242], [246]
• Tower cableways, [252]
• Trade wastes. See Industrial wastes.
• Traps, in catch-basins, [107]
  • grease, gasoline, and oil, [108], [109]
  • in street inlets, [104], [105]
• Travis tank, [427], [428]
• Tree roots, [333], [340]
• Tremie, [187], [188]
• Trench, backfilling, [328]–331
  • blasting in, [244], [269]
  • bottom, shape of, [241], [304], [311]
  • breaking surface, [243], [244]
  • drainage, [256]–263
  • excavating, by hand, [242]–245
    • machine, [244]–256
  • guarding and lighting, [221]
  • layout of tasks, [243]
  • length of open, [241], [248]
  • line and grade, [281]–284
  • location, [243], [281]
  • opening, [243], [244]
  • pumps, [256]–263
  • sheeting, [270]–280
  • width, [240], [241], [246]
• Trestle excavators, [250], [251]
• Trickling filter, [437]–452
  • advantages, [438], [439]
  • covers for, [451]
  • depth, [441], [442]
  • description, [437], [438]
  • dimensions, [442]
  • distribution of sewage, [442]–451
  • dosing siphon, [446]–451
  • dosing tank, [446]–451
  • head lost, [438]
  • insects, [438]
  • material, [441]
  • nozzles, [442]–451
    • layout, [447]–451
  • odors, [438], [439]
  • operation, [441]
  • rate, [441]
  • results, [439], [440]
  • siphon size, [449]–451
  • underdrainage, [451], [452]
  • unloading, [431], [437]
• Tripod drill, [265]
• Triton, [295]
• Troubles with sewers, causes, [333]
• Trumpet arch, [121]
• Trunk sewer, defined, [7]
• Tunnels, [283]–294
  • backfilling, [331]
  • breast boards, [288]
  • brick invert, [313]
  • compressed air in, [292]–294
  • concrete construction, [320], [321]
  • depth of cover, [284]
  • line and grade in, [283]
  • machines, [290]
  • rock, [290]–292
  • shafts, [284]–286
  • shield, [288]–290
  • timbering, [284]–288
  • ventilation, [291], [292]
• Turbidity of sewage, [353]
• Turbine, for cleaning sewers, [340]
  • pumps, [130], [132]
  • steam, [146], [147]
• Typhoid fever, [364]
• U-shaped sewer section, [67], [69], [71]
• Underdrains for, sewers, [126]
  • trickling filters, [451], [452]
• Underground surveys, [18]–20
• Unexpected situations, [235]
• Uniformity coefficient of sand, [456]
• Unloading of filters, [431], [437]
• Urea, [367]
• Valuation of sewers, [332], [348]–351
• Velocities, depositing, [395]–397
  • distribution of, [51]
  • flow in sewers, [90]
  • over surface of ground, [42]
  • limiting for sedimentation, [396], [397]
  • limiting in sewers, [396], [397]
  • principles of flow in sewers, [51]
  • transporting, [396]
• Ventilation, air pressures, [291]
  • compressed air, [292]–294
  • pipes, [291]
• Ventilation, of sewers, [102], [103], [335]
  • tunnel, [291]
• Vertical sheeting, [270]–274
• Vitrified clay. See Clay vitrified.
• Volatile matter in sewage, [357]
• Volute pumps, [130], [132], [154]
• Vouissoir arch analysis, [204]
• Wakefield piling, [273]
• Wales, [288]
• Waste pipe, defined, [7]
• Wastes. See Industrial wastes.
• Water consumption, [31]–33
  • flow of, [51]–77
  • rate of steam engines, [144], [145]
  • supply and sewage flow, [31]–33
• Watershed. See Drainage area.
• Weight, of backfill, [199]
  • of building material, [201]
  • of moving loads, [200], [202]
• Well, hole, [101]
  • points, [262], [263]
• Wheel excavator, [246]–250
• Wing screen, [384]
• Wood, forms. See Forms.
  • pipe, materials, [164], [165], [190], [192], [193]
    • design, [197], [198]
  • working strength of, [277]
• Work, extra, [227]
  • preliminary to design, [9]
  • Sunday, night, and holiday, [221]
• Workmen, competent, [227]
  • dishonesty, [233], [234]

---

[1]. Frontinus and the Water Supply of Rome, p. 81, by Clemens Herschel.

[2]. Estimated by G. W. Fuller, Trans. Am. Society of Civil Engineers, Vol. 44, 1905, p. 148. The total population connected with sewerage systems was assumed to be the total population in the United States in cities over 4000 in population.

[3]. Estimated by Metcalf and Eddy, American Sewerage Practice, Vol. III, p. 240.

[4]. Computed from report of the United States Census, 1920, on the same basis as Fuller’s estimate for 1905.

[5]. Cosgrove, History of Sanitation.

[6]. Sedgwick: Sanitary Science and Public Health.

[7]. No detrimental effect on the public health was noted as a result of this condition however. It has never been conclusively proven that such nuisances are detrimental to the public health.

[8]. Moore and Silcock, Sanitary Engineering, p. 67, 1909.

[9]. Similar to the definition proposed by the Am. Public Health Assn.

[10]. Definition recommended by Am. Public Health Assn.

[11]. Ibid.

[12]. Ibid.

[13]. Eng. News, Vol. 76, 1916, p. 781. See also Eng. News-Record, Vol. 85, 1920, pp. 22, 1175.

[14]. For a more extensive treatment of the subject see Principles and Methods of Municipal Administration by W. B. Munro, 1916.

[15]. Eng. Record, Vol. 74, 1916, p. 263.

[16]. Professional paper No. 46, United States Geological Survey, 1906, p. 97.

[17]. United States Geological Survey, Water Supply paper No. 257, 1911.

[18]. From Eng. Cont., Vol. 41, 1914, p. 698.

[19]. Max. represents only the average maximum, not the greatest maximum.

[20]. Eng. News-Record, Vol. 80, page 1233, 1918.

[21]. Infiltration of Ground Water into Sewers. Transactions of the American Society of Civil Engineers, Vol. 76, 1913, p. 1909.

[22]. A comprehensive discussion of rainfall formulas will be found in Vol. 54 of the Transactions Am. Society of Civil Engineers, 1905.

[23]. Formula devised by H. E. Babbitt from Allen’s 25–year curve.

[24]. See Note under Table 14.

[25]. Sewerage by A. P. Folwell.

[26]. From an article by E. Kuichling in Transactions American Society of Civil Engineers, Vol. 65, 1909, p. 399.

[27]. Trans. Am. Society Civil Engineers, Vol. 58, 1907, p. 483.

[28]. Trans. American Society of Civil Engineers, Vol. 58, 1907, p. 498.

[29]. Ibid.

[30]. The principles governing the run-off from large areas are explained in Elements of Hydrology, by A. F. Meyer, 1917.

[31]. Transactions of the American Society of Civil Engineers, Vol. 51, 1903, p. 11.

[32]. Municipal and County Engineering, Vol. 58. 1920, p. 164.

[33]. Industrial waste Treated as ground water.

[34]. For diagrams for the Solution of the Rational Method, see Eng. News-Record, Vol. 83, 1919, p. 868 and Vol. 85, 1920, p. 151.

[35]. Municipal and County Engineering, October, 1909.

[36]. “Cleaning and Flushing Sewers.” Journal of the Association of Engineering Societies, Vol. 33, 1904, p. 212.

[37]. Notes on the Design and Principles of Sewage Siphons, Eng. News-Record, Vol. 85, 1920, p. 1041.

[38]. From A. E. Phillips, Trans. Am. Society of Municipal Improvements, 1898, p. 70.

[39]. Trans. Am. Society of Civil Engineers, Vol. 15, 1886.

[40]. True Siphon at East Providence, Eng. News-Record, Vol. 85, 1920, p. 862.

[41]. “The Effect of Mouthpieces on The Flow of Water Through a Submerged Short Pipe,” by F. B. Seely. Bulletin No. 96, 1917, of the Eng’g. Experiment Station of the University of Illinois.

[42]. Trans. Am. Society of Civil Engineers, Vol. 49, 1902.

[43]. Described by W. L. Stevenson before the Boston Society of Civil Engineers in 1916.

[44]. Multiple Outlet for Calumet Intercepting Sewer, by S. T. Smetters, Eng. News-Record, Vol. 83, 1919, p. 728.

[45]. “Direct Acting Steam Pumps,” by F. R. Nickel, 1915.

[46]. From Heat Engines, by Allen and Bursley.

[47]. “The Economy Resulting from the Use of Variable Speed Induction Motors for Driving Centrifugal Pumps” by M. L. Enger and W. J. Putnam. Journal Am. Water Works Ass’n., 1920, Vol. 7, p. 536.

[48]. C. A. Hague in Trans. Am. Society of Civil Engineers, Vol. 74, 1911, p. 20.

[49]. Includes screen chamber, collecting reservoir, and building.

[50]. Computed on the assumption that the pumps may be operated at 50 per cent overload for short periods, the rated capacity being equal to the loads given in Table 33.

[51]. For description of type see note under Table 35.

[52]. Proceedings Illinois Society of Engineers, 1916, page 81.

[53]. Municipal Engineers’ Journal for April, 1918.

[54]. Workability involves ease in placing and smoothness of working.

[55]. Johnson’s Materials of Construction, 5th Edition, 1918, p. 432.

[56]. Trans. Am. Society of Civil Engineers, Vol. 59, 1907, p. 146.

[57]. L. N. Edwards, Trans. Am. Society Testing Materials, 1918, and R. B. Young, Eng. News-Record, Vol. 82, 1919, p. 33.

[58]. Bulletin No. 1, Structural Materials Research Laboratory, Lewis Institute, Chicago, Illinois.

[59]. Proportioning Concrete by Voids in the Mortar, A. N. Talbot, read before Am. Society Testing Materials, June 22, 1921. Abstract in Eng. News-Record, Vol. 87, 1921, p. 147.

[60]. Trans. Am. Society of Civil Engineers, Vol. 81, 1917, p. 1122.

[61]. See also Tentative Specifications for Concrete and Reinforced Concrete submitted by the Joint Committee to its Constituent Organizations, June 4, 1921.

[62]. Journal Illinois Society of Engineers for 1916, p. 75.

[63]. See A. S. T. M. Standards for 1918, p. 148.

[64]. Trans. Am. Society Civil Engrs., Vol. 82, 1918, p. 459.

[65]. See Trans. Am. Society Civil Eng., Vol. 82, 1918, p. 482.

[66]. See Trans. Am. Society Civil Engr., Vol. 41, 1899, p. 76, and Vol. 82, 1918, p. 433, Eng. News, Vol. 74, 1915, p. 400, and Vol. 75, 1916, p. 911.

[67]. Trans. Am. Soc. Civil Engrs., Vol. 82, 1918, p. 433.

[68]. Bulletin No. 31 of the Engineering Experiment Station of the Iowa State College of Agriculture.

[69]. From bulletin No. 31, Engineering Experiment Station, Iowa State College of Agriculture.

[70]. From Bulletin No. 31, Engineering Experiment Station, Iowa State College of Agriculture.

[71]. From Bulletin No. 31, Engineering Experiment Station, Iowa State College of Agriculture.

[72]. From Vouissoir Arches by Cain.

[73]. Baker’s Masonry, 10th Edition, p. 676.

[74]. Business Law for Engineers, C. Frank Allen, McGraw-Hill, 1917; Engineering Contracts and Specifications, J. B. Johnson, McGraw-Hill, 1904; Contracts in Engineering, J. I. Tucker, McGraw-Hill, 1910; The Law Affecting Engineers, W. V. Ball, Archibald Constable, 1909; Law and Business of Engineering and Contracting, C. E. Fowler, McGraw-Hill, 1909; The Economics of Contracting, D. J. Hauer, E. H. Baumgartner, 1915; The Elements of Specification Writing, R. S. Kirby, John Wiley & Son, 1913; Contracts, Specifications and Engineering Relations, D. W. Mead, McGraw-Hill, 1916; Engineering and Architectural Jurisprudence, J. C. Wait, John Wiley, 1912.

[75]. See article by E. W. Bush in Eng. News-Record, Vol. 85, 1920, p. 122.

[76]. An unbalanced proposal is one in which the bids on some of the items are obviously low and on other items are obviously or suspiciously high. The purpose of submitting unbalanced bids is to keep secret the true or supposed cost of the work to the contractor or to obtain more money by bidding high on those items which are believed to have been underestimated by the Engineer. A low bid is made on other items in order to keep down the total amount of the bid.

[77]. Taken mainly from specifications of the Sanitary District of Chicago and the Baltimore Sewerage Commission, with miscellaneous selections from other sources.

[78]. Restrictions are placed on work done outside of ordinary working hours in order that the Contractor may not perform work in the absence of an engineer or inspector.

[79]. Cost Keeping and Management, by Gillette and Dana. Practical Cost Keeping for Contractors, by F. R. Walker. Cost Keeping in Sewer Work, by K. O. Guthrie in Eng. Contracting, Vol. 28, p. 238, 1905. Sewer Construction Records at Scarsdale, Eng. News-Record, Vol. 83, p. 111, 1919.

[80]. See Planning and Progress on a Big Construction Job, by Chas. Penrose, Eng. News-Record, Vol. 84, 1920, pp. 554 and 627.

[81]. See also “Ownership and Operation of Trench Excavators by the Water Department of Baltimore,” by V. B. Seims, presented before Am. Water Works Association, June 9, 1921.

[82]. Eng. and Contracting, Vol. 48, 1917, p. 492.

[83]. Earth Excavation by A. B. McDaniel.

[84]. Courtesy, Sanitary District of Chicago.

[85]. See article by J. R. Gow, Journal New England Waterworks Ass’n, Sept., 1920, also Public Works, Vol. 50, p. 98.

[86]. Diameter of diaphragm.

[87]. Gallons per minute.

[88]. Eng. News, Vol. 75, 1916 p. 1050.

[89]. Mun. Engineering, Vol. 53, p. 6.

[90]. For types of drill bits see article by T. H. Proske, Mining and Scientific Press, March 5, 1910.

[91]. These intermediate holes are seldom more than 3 feet apart.

[92]. Earth Pressures, Old Theories and New Test Results, Eng. News-Record, Vol. 85, 1920, p. 632.

[93]. Trans. Am. Society Civil Eng’rs, Vol. 60, 1908.

[94]. Adopted by the Am. Ry. and Maintenance of Way Ass’n in 1907.

[95]. Tunneling Machines Successful on Detroit Sewers, Eng. News-Record, Vol. 84, 1920, p. 329.

[96]. Rules on Compressed-Air Work of N. Y. State Industrial Commission, Eng. News-Record, Vol. 85, 1920, p. 1225.

[97]. Taken mainly from the Engineer Field Manual of the U. S. Army; Safety Factors in the Use of Explosives by W. O. Snelling, Technical Paper No. 18, U. S. Bureau of Mines; and an article in Eng’g and Contracting, Vol. 52, 1919, p. 585.

[98]. See paper by C. T. Hall before Am. Inst. Chemical Engineers.

[99]. Per cubic yard of material displaced.

[100]. Eng. News, Vol. 75, 1916, p. 592.

[101]. Pressure of Concrete on Forms Measured in Tests, by E. B. Smith, before Am. Concrete Institute, Feb. 15, 1920. Abstracted in Eng. News-Record, Vol. 84, 1920, p. 665.

[102]. See, also, Concrete Form Design, by E. F. Rockwood, Eng. and Contracting, Vol. 55, 1921, p. 528.

[103]. Includes 6 cents per foot for excavation. Labor for this was 58 per cent of the total labor cost.

[104]. Cement at $1.25 per barrel.

[105]. Mun. Journal, Vol. 36, 1914, p. 736.

[106]. Mun. Journal, Vol. 39, 1915, p. 911.

[107]. Formerly the Municipal Journal.

[108]. See Eng. Record, Vol. 75, 1917, p. 463.

[109]. Eng. Record, Vol. 73, 1916, p. 141, and Eng. News-Record, Vol. 79, 1917, p. 1019.

[110]. Eng. Record, Vol. 72, 1915, p. 690.

[111]. Eng. Record, Vol. 71, 1915, p. 256.

[112]. Eng. and Contr., Vol. 41, 1914, p. 250.

[113]. H. J. Kellogg in Journal Connecticut Society of Civil Engineers, 1914, and Technical Paper 117, U. S. Bureau of Mines.

[114]. Eng. News, Vol. 70, 1913, p. 1157.

[115]. Technical Paper No. 117, U. S. Bureau of Mines.

[116]. Eng. News, Vol. 71, 1914, p. 84.

[117]. Eng. News, Vol. 71, 1914, p. 82.

[118]. Similar to definition proposed by the Am. Public Health Ass’n.

[119]. Economic Values in Sewage and Sewage Sludge, by Raymond Wells, Proceedings Am. Society Municipal Improvements, Nov. 12, 1919. Eng. News-Record, Vol. 83, 1919, p. 948.

[120]. Sample boiled for five minutes.

[121]. Sample immersed in boiling water for 30 minutes.

[122]. Four months.

[123]. One week in March, 1914.

[124]. R represents any chemical element such as K, Na, etc.

[125]. Standard Methods of Water Analysis, American Public Health Association, 1920.

[126]. Routine tests are ordinarily incubated for this period only, and if not decolorized in this time are recorded as stable.

[127]. Determination of the Biochemical Oxygen Demand of Sewage and Industrial Wastes, by E. J. Theriault, Report of the U. S. Public Health Service, Vol. 35, May 7, 1920, No. 19, p. 1087.

[128]. Standard Methods of Water Analysis, American Public Health Association, 1920.

[129]. Jordan, General Bacteriology, 1909, p. 91.

[130]. Ibid.

[131]. Reprinted in Vol. III of Contributions from the Sanitary Research Laboratory of Massachusetts Institute of Technology.

[132]. Formerly Chief Engineer of the Sanitary District of Chicago.

[133]. From “Sewage,” by Samuel Rideal, 1900, p. 16.

[134]. See Am. Civil Engineers’ Pocket Book, Second Edition, p. 982.

[135]. Trans. Am. Society Civil Engineers, Vol. 58, 1907, p. 988.

[136]. Not defined by the American Public Health Association.

[137]. Trans. Am. Society Civil Engineers, Vol. 78, 1915, p. 892.

[138]. Removal of Suspended Matter by Sewage Screens, Cornell Civil Engineer, 1914. Abstracted in Engineering and Contracting, Vol. 41, 1914, p. 451.

[139]. “The Clarification of Sewage by Fine Screens,” Trans. Am. Society Civil Engineers, Vol. 78, 1915, p. 1000.

[140]. Langdon Pearse, Trans. Am. Society Civil Engineers, Vol. 78, 1915, p. 1000.

[141]. Meshes per inch.

[142]. See article by Henry Ryon in Cornell Civil Engineer, 1910.

[143]. The hydraulic coefficient is defined as the rate of settling in mm. per second.

[144]. Definition suggested by the American Public Health Association.

[145]. Computed from formula by Gilbert in “Transportation of Debris by Running Water,” U. S. Geological Survey, Professional Paper No. 86, 1914. Diameter in mm. = 1.28 (velocity)^2.7
Sp. gv. − 1.

[146]. Computed from Annual Report of the Superintendent of Sewers, Nov. 30, 1919, and 1920.

[147]. These figures are for 1919.

[148]. These figures are for 1905.

[149]. These figures are for 1902.

[150]. Report of the Ohio State Board of Health, 1908, page 425.

[151]. Definition proposed by the Am. Public Health Assn.

[152]. See Eng. News. Vol. 73, 1915, p. 410.

[153]. Sewage Treatment from Single Houses and Small Communities, by L. C. Frank. U. S. Public Health Service, Bulletin 101, 1920.

[154]. Eng. News-Record, Vol. 78, 1917, p. 566.

[155]. Municipal Engineering, Vol. 54, p. 149.

[156]. Eng. Record, Vol. 68, 1913, p. 452.

[157]. Am. Sewerage Practice, Vol. III, p. 437.

[158]. Trans. Am. Society Civil Engineers, Vol. 83, 1920, p. 337.

[159]. Eng. News-Record, Vol. 83, 1919, p. 510.

[160]. See Eng. News, Vol. 70, 1913, p. 1112; Eng. Record, Vol. 68, 1913, p. 440, and Eng. News, Vol. 75, 1916, p. 1028.

[161]. See Eng. Record, Vol. 67, 1913, p. 232.

[162]. The use of half-spray nozzles is not always advocated as it is considered that their use does not markedly improve the distribution. Where half nozzles are used, a margin of 18 inches to 2 feet should be allowed between the edge of the filter and the nozzle, to prevent the blowing of raw sewage from the filter.

[163]. From paper by E. G. Bradbury in Proceedings of the Ohio Eng. Society, 1910, p. 79.

[164]. The effective size of sand is the diameter in millimeters of the largest grain in that 10 per cent, by weight, of the material which contains the smallest grains.

[165]. The uniformity coefficient is the ratio of the diameter of the largest particle of the smallest 60 per cent, by weight, to the effective size.

[166]. Interest at 6 per cent.

[167]. Worcester figures.

[168]. This method may show a profit from the sale of sludge.

[169]. Sewage Disposal, 1919, p. 223.

[170]. See Eng. News, Vol. 9, 1883, p. 203, and Vol. 29, 1893, p. 27.

[171]. American Sewerage Practice, Vol. III.

[172]. Reference 11, at end of this chapter.

[173]. Reference 15.

[174]. Reference 2.

[175]. For mechanical methods of drying sludge, see Reference 22, p. 1127, and No. 33, p. 843.

[176]. Reference 10.

[177]. Reference 13.

[178]. University of California, Bulletin 251, 1915.

[179]. Reference 25.

[180]. See Report by Black & Phelps of Metropolitan Sewerage Commission, 1911, reprinted as Vol. VII of Contributions from the Sanitary Research Laboratory of the Massachusetts Institute of Technology.

[181]. See Reports, Mass. State Board of Health.

[182]. Reference 47.

[183]. Reference 10.

[184]. Reference 10.

[185]. Reference 10.

[186]. Hatton, reference 33.

[187]. Reference 18.

[188]. Reference 1, at end of this chapter.

[189]. Reference 2.

[190]. Reference 6.

[191]. Reference 5.

[192]. Reference 6.

[193]. Reference 6.

[194]. Reference 8.

[195]. Reference 20.

[196]. Reference 17.

[197]. Reference 19.

[198]. Reference 21.

[199]. Reference 24.

[200]. Inorganic Chemistry, by Alexander Smith.

[201]. American Public Health Association definition.

[202]. Sewage Sludge by Allen.

[203]. Sewage Disposal by Kinnicutt, Winslow and Pratt.

[204]. Sewage Disposal by Fuller.

[205]. Sewage Sludge by Allen.

[206]. From Eng. News-Record, Vol. 84, 1920, p. 995.

[207]. A Simple Mechanical Control for Dosing Sewage Beds, by P. Thompson, Eng. News-Record, Vol. 84, 1920, p. 1018.

[208]. Sewage Disposal by Kinnicutt, Winslow and Pratt.

[209]. Design of Siphon by G. H. Bayles, Eng. News-Record, Vol. 84, 1920, p. 974.

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TRANSCRIBER’S NOTES

1. Silently corrected typographical errors and variations in spelling.
2. Archaic, non-standard, and uncertain spellings retained as printed.