484 



Index and Glossary 



composition of, 110; decomposi- 

 tion, aerobic and anaerobic action 

 in, 117; disposal, bacteriological 

 methods of, 107, -- chemical 

 methods of, 106, 107, importance 

 of, 110, problem of, 103, 109; 

 examination of, 111; factory wastes 

 in, 123; farming, objections to, 133; 

 farms, 112, 127, 131; intermittent 

 filtration of, 115; irrigation, value 

 of, 125, 127; preliminary treatment 

 of, 132; purification, relation of 

 temperature to, 118; purification, 

 sanitary efficiency of, 134; source 

 of, 110; spent liquors in, 124; steri- 

 lization of, 108; value of, per ton, 

 127. 



Shape of bacteria, 15. 



Silage corn, 454. 



Size of bacteria, 17. 



Sludge (the material that settles out 

 of sewage, or is precipitated out 

 by means of chemicals), 126, 132. 



Smoking of foods, 440. 



Soft cheeses, 422; lactic-acid bacteria 

 in, 424; peptonizing bacteria in, 

 425; production of, in the U. S., 

 423. 



Soil, aerobic species in, 139; air, com- 

 position of, 150; anaerobic species 

 in, 139; bacteria, effect of lime on, 

 142, influence of tillage on, 141, 

 numbers of, at surface, 143, 

 physiological efficiency of, 160, 

 relation of crops to, 139, varia- 

 tions in vigor of, 159; clogging of, 

 by sewage, 129; colon bacillus in, 

 75; distribution of nitrogen in, 

 199; fertility and bacteria, 135; 

 formation of nitrates in, 178; gases, 

 151; humus, decomposition of, 

 by bacteria, 146, nitrogen com- 

 pounds in, 156; improvement, 242; 

 inoculation, 221-226, 230, 236; 

 leaching of nitrates from, 158, 174; 

 loss of nitrogen in, 157; nitrifying 

 power of, 179, 180; nitrogen, in- 



crease of, 190; numbers of bacteria 

 in, 137; proportion of nitrogen in, 

 155; removal of nitrogen from, 191; 

 source of nitrogen in, 155. 



Soils, ammonifying power of, 167; 

 arid, proportion of humus in, 145; 

 cultivated, exhaustion of humus in, 

 152; fallow, 267, 273; greenhouse 

 and market-garden, denitrification 

 in, 188; liming of, 278; sandy, green- 

 manures in, 241, 243, humus in, 

 153, value of crimson clover on, 

 249; sterilized, carbon dioxid in, 

 148. 



Souring of canned vegetables, 436. 



Soybeans, 230, 245. 



Spherical bacteria, 13, 14. 



Spiral bacteria, 13, 14. 



Spirilla (spiral-shaped bacteria), 17. 



Spontaneous generation (the forma- 

 tion of living organisms out of dead 

 matter), 3, 4. 



Spore-formation, 22. 



Spore-forming bacteria, 23. 



Spores (certain cells, formed in some 

 species of bacteria, and capable of 

 withstanding adverse conditions 

 much better than the bacteria 

 themselves), 22; discovery of, 5; 

 vitality of, 23. 



Starters, building up of, 407. 



Starters (pure or impure cultures of 

 lactic-acid bacteria added in con- 

 siderable proportion to cream that 

 is to be ripened), definition of, 406; 

 natural, 407, 409; preparation of, 

 407, 408; pure culture, 407^10. 



Sterilization (the complete destruc- 

 tion of bacteria and other micro- 

 organisms in any material), 23, 24; 

 by superheated steam, 25; of milk, 

 388, 389; under increased pressure, 

 25. 



Stilton cheese, 422, 426. 



Stocking, 365. 



Stored water, bacteria in, 82. 



Storer, 127. 



