B _B. choleræ_ suis, 31 _B. cloacæ_, 31 _B. coli_, aftergrowths, 57 in sewage, 6, 7 in water, 9, 28, 31 standard, 46 viability of, 52, 55 _B. cuticularis_, 53 _B. fæcalis alkaligenes_, 31 _B. enteritidis_, 31 _B. enteritidis sporogenes_, 53 _B. lactis ærogenes_, 31 _B. subtilis_, 53 _B. tetani_, 9 _B. typhosus_, 9, 10, 30, 31 Bacteria surviving chlorination, 50 aftergrowths, 55 nature of, 53 spores, 57 Benzidine, 83 Bleach, analysis of solution, 79 as deodourant, 3, 6 as sewage disinfectant, 6, 7 at Adrian, 11 at Boonton, 11, 16 at Bubbly Creek, 11 composition, 14 decomposition of, 25 discovery, 2 germicidal velocity, 20, 21 hydrolysis, 18, 19 production, 3 stability of, 17 toxic action, 22 treatment, 72 control of, 78 cost, 86 dosage regulation, 75 in France, 78 losses in, 81 mixing tank, 73 plant design, 72 storage tank, 75 Brest experiments, 5 C Carnallite, 1 Chicago, typhoid rate, 138 Chloramine, 114 at Denver, 124, 126 at Ottawa, 28, 116 contact period, 123 cost of, 124 decomposition of, 126 experimental results, 119 germicidal power, 116 operation of process, 126 plant design, 120 preparation of, 115 ratio of chlorine and ammonia, 116, 122 tastes and odours, 28, 64, 117 toxic action, 22, 29 Chlorides, effect of, 20 Chlorine, and ammonia, 24, 25 discovery of, 1 disinfection, effect of pabulum, 4 general reactions, 28 hydrate, 103 detection of, 81 effect on flowers, 68 estimation of, 81 in sanitary work, 4 medicinal dose, 67 oxygen equivalent, 23 liquid, 89 advantages of, 97 cost of treatment, 101 disadvantages of, 101 germicidal efficiency, 99 machines, 89 peroxide, 9 water, 102 corrosion of pipes, 69 damage to seeds, 68 decomposition of, 15 heat of formation, 27 Chlorometer, 84 Chloros, 8 Chlorozone, 105 Colour, effect on dosage, 33 Columbus, typhoid rates, 137 Complaints, 62 Contact period, effect on dosage, 44 effect on taste, 43 usual practice, 45 Cost of bleach plant, 85 bleach treatment, 86 liquid chlorine treatment, 101 Crossness experiments, 5 D Dayton cell, 107 DeChlor filters, 87 Denver, chloramine treatment, 124, 126 Dichloramine, 128 Disinfectants, 50 Disinfection, early views of, 3 Dosage, 30 determination of, 46 effect of, admixture, 39 colour, 33 contact period, 43 initial contamination, 32 light, 45 oxidisable matter, 32 standard of purity, 30, 32 temperature, 34, 36 turbidity, 45 for military work, 48 regulation of bleach, 75 relation to oxygen absorbed, 36 tanks, 75