598 



Index. 



Milk, odors and flavors in, 14 : deodoriz- 

 ing of, 16; cooling of, 17, 34; value 

 of, in heat units, 33. 



Mixed herbage, nitrogen used by, 82. 



Molecules, 6 ; composed of atoms, 7 ; 

 not in contact, 8 ; movements of, 8, 

 13 ; diffusion of, 8 ; relation to elastic- 

 ity, 8; velocities of, 9; number ui per 

 gram, 10, 11 ; size of, 9 : relation of 

 to steam pressure, 19 : movements in 

 evaporation, 24 ; dissociation of in so- 

 lution, 48. 



Monsoons, 570. 



Morin Gen., draft of wagons, 443 ; fric- 

 tion, 540. 



Motors, farm, 486. 



Mulches, effectiveness of, in marsh soil, 

 186 ; sandy loam, 186 ; clay loam, 

 186 ; character influenced by frequency 

 o*f cultivation, 187 : depth of, 189, 

 191 : depth and frequency of stirring 

 should vary with season, 191 ; de- 

 veloped by rolling, 193 : other than 

 soil, 193; for alfalfa fields, 193; for 

 meadows. 193. 



Miintz. denitrification. 90. 



Muscles, as motors, 487 ; temperature of 

 in action, 488 : power of, 488 : of hock, 

 49*. 



Mustard, temperature of germinatioa. 

 212 



Nitrates, seasonal changes under corn, 

 96: in cultivated and uncultivated 

 ground. 100 : relation of to total sol- 

 uble salts. 101 ; closeness of removal 

 of by plants, 101 ; in fallow and crop- 

 ped ground compared, 103. 10.~> : loss 

 of during winter, 104 ; development 

 influenced by cultivation, 105 ; by late 

 fall plowing, 182 ; loss of lessened by 

 cover crops, 183 ; developed by early 

 tillage, 185 ; air required for develop- 

 ment 206 : temperature for formation, 

 212, 215. 



Nitric acid, amount of in soils, 84 : In 

 fallow ground, 84 ; action of ozone and 

 peroxide of hydrogen in formation of, 

 86 ; formation of, 89 : formed by niter 

 germs, 89 ; in atmosphere, 557. 



Nitric nitrogen, in soil, 84 ; limiting 

 amount for corn and oats, 102. 



Nitrification, process of, 89 ; tempera- 

 ture for. 212. 



Niter germs, forming nitric acid, 89 ; 

 temperature for growth of, 212. 



Nitrogen, essential to plant life, 69; 

 form of used by plants, 70 ; from 

 humus, 76 ; amount removed by crops, 

 79, 82 ; amount stored in soils, 82 ; 

 forms of occurrence in soil, 82 ; dis- 

 tribution of in soil, 83 ; source of in 

 soil, 85 : accumulated bv symbiosis, 

 87 ; Increased in soil, by ventilation, 

 206 ; of plants derived from air, 554 ; 

 amount in air, 556 ; functions of, 558. 



Nobbe, function of potash, 70. 

 Nobert, ruling of ylass by, 9. 

 Nollet, Abbe, 41. 

 Northers, of Texas, 586. 



Oak value of one pound of In heat 

 units, 35. 



Oats, water used by, 141 ; nitric nitrogen 

 limiting growth, 102 ; extent of root 

 development, 150, 155. 



Odors, 8, 13; in dairy products. 14; 

 accumulation of in dairy products. 14 ; 

 removal of, 16. 



Oemler, specific heat of soils, 215. 



Orchards, late tillage of to conserve 

 moisture, 182; early plowing for, 185. 



Osmosis, phenomena of, 41; principles 

 of, 42; measurement of pressure, 43; 

 In plant feeding, 46. 



Osmotic pressure, 42; influence of tem- 

 perature on, 46; increased by dissocia- 

 tion of salts, 48. 



Oxalic acid, action in plant growth, 70, 



Ox-bows. 55, 57, 62. 



Oxygen, absorption of in breathing, 6 ; 

 rate of molecular motion, 9 ; size of 

 molecules, 10 : essential to germina- 

 tion, 204 : uses in soil, 204 ; essential 

 to plant breathing, 204 ; amount con- 

 sumed by man varies with tempera- 

 ture, 345 ; demand for necessitates 

 ventilation, 350 ; amount in air, 557 ; 

 functions of, 557. 



Ozone action of in forming nitric acid, 

 86 ; in atmosphere, 557. 



Paper, function of In walls. 348 ; es- 

 sential qualities, 348; for ventilators, 

 364 ; for silos, 400, 407, 415. 



Peas, temperature for germination, 212. 



Peat, formation of, 62. 



Percolation, rate Influenced by pore 

 space, 115; of soil moisture, 158; 

 rate of through sand and soil, 1"9 ; 

 through dry soil. 160: rate of in- 

 creased by sub-soiling, TOO; influence 

 of on soil ventilation. 209 ; rise of 

 ground water due to, 260. 



Pfeffer. osmotic pressui-" M. 4^. 



Peroxide of hydrogen, action of In form- 

 ing nitric acid, 86. 



Perspiration controls body tempera- 

 ture. 33. 



Phosphoric acid, in soil, 74, 78, 80; 

 amount removed by crops. 79. 



Phosphorus essential to plant life, 69 ; 

 function of, 70. 



Pillars, strength of, 330; bearings for, 

 330. 



Piston, of steam engine. 519 ; of gasoline 

 engine, 525 ; size of for pumps. 547. 



