596 



Index. 



Floors, stable, 374 ; temperature of, 

 375 ; wood, 377 ; stone, 378 ; cement, 

 379 ; comparative cost, 383 ; manure 

 drop, 388. 



Foaming, in boiler, 513. 



Foot-pound 18, 27 ; equivalent In heat 

 unts, 28. 



Foot-ton, 18, 27. 



Frank, symbiosis, 88. 



Frear, Dr., soil temperatures, 214. 



Freezing, with ice and salt, 30. 



Friction, 538 ; kinds, 538 ; between sol- 

 ids, 539 ; rolling, 540 ; of fluids, 540 ; 

 lubricants, 541 ; influence of grit on, 

 542. 



Furrows, dead and back, 49. 



Gage, cocks, 510; glass, 510; pressure, 

 511. 



Galvanized iron, silo lining, 414. 



Gardens, early plowing of to save moist- 

 ure, 185 ; floating, 205 ; cultivators for, 

 230. 



Gasoline engine, 522 ; parts, 523 ; work- 

 ing cycle, 523 ; cooling of parts, 524 ; 

 types of, 524 ; construction, 525, 

 cylinder, 525, pumping mechanism, 

 525, governor, 512*3, valve mechan- 

 ism, 528 ; igniting charge, 529 ; lubri- 

 cation, 529 ; gasoline for, 530. 



Gasoline, for engine, 530. 



Germination, interfered with by green 

 manure, 201 : retarded by too early 

 seeding, 201 ; oxygen needed for, 204 ; 

 temperatures for, 213 ; rate of in- 

 fluenced by soil temperature, 214 ; of 

 weed seeds, 225. 



Glacial soils. 57. 



Governor, 521, 526. 



Grade, 428; effect on draft, 429; steep- 

 est admissible, 430; conditions which 

 determine, 433. 



Grain, ratio of to straw, 80 ; harrowing 

 after up. 192, 224; rolling after up, 

 192, 224 : fitting seed bed with disk 

 harrow, 235. 



Grapes, affected by alkalies, 93. 



Gravel, 457 ; for road surface, 456 ; char- 

 acter, 458, 459 ; altering texture, 458. 



Gravel roads, 459. 



Green manures, danger from, 201 ; plow- 

 Ing under, 253. 



Grinding, by wind mill, 531, 536. 



Ground water, movements of, 255 ; con- 

 tours of surface of, 257, 259 ; changes 

 In level of, 260 ; elevation of through 

 percolation, 260 ; changes with season, 

 260 : general movement of across wide 

 areas. 270 : fluctuations in rate of flow 

 of, 270 ; changes in rate of flow 

 due to barometric changes, 271 : 

 diurnal changes in rate of flow 

 of, 271, 272 ; rise of away from 

 Jrainage outlets. 293. 295 : observed 



surface In tile-drained field, 297 : rats 

 of change in level between tile drains, 

 297. 



Guard cells, 143; action of, 144; loss 

 of water through, 145. 



Haberlandt, temperature of germination, 

 214. 



Hail, formation of, 524. 



Harrow, spike-tooth, to save moisture. 

 185 ; disk harrow to save moisture, 

 185 ; for small grain after It is up, 

 192 ; for corn and potatoes after they 

 are up, 192 ; tilting, 225 ; use in kill- 

 Ing weeds, 224, 225 ; spring tooth, 233 ; 

 smoothing type, 236 ; should follow 

 roller, 237. 



Harrowing, influence of on soil ventila- 

 tion, 210 ; after plowing, 252. 



Hay, arrangements for unloading, 391. 



Heat, 25 ; mechanical equivalent, 28 ; 

 specific, 29 ; latent, 29, 581 ; from 

 green and wet woods, 35 ; control of in 

 animals, 343 ; normal for animals, 

 343 ; construction to prevent change, 

 345 ; produced by muscular action, 

 488 ; loss from engines 506. 



Heat unit, 28 ; number of consumed in 

 melting and in evaporation, 30. 220 ; 

 number of, in one pound of beef fat, 

 and one pound of milk, 33 ; vaiue of 

 wood in, 35 ; value of coal In, 502. 



Hedges, as wind breaks, 202. 



Hellriegel, on symbiosis, 87; effect of 

 temperature on rate of germination, 

 214. 



Hens, air breathed by, 854, 355. 



Herbst, respiration, 353. 



Hilgard, soil analyses, 71, 74, 75; 

 humus of arid climates, 76; alkali 

 salts limiting plant growth. 93 ; on 

 hygroscopic moisture, 177, 179. 



Hock Joint, 495. 



Hoops, for silos, 399, 422. 



Horse, normal temperature of, 344 ; air 

 respired by, 354 ; supply of air for, 

 355 ; as a motor, 487 ; generation of 

 energy by, 489, expended In hauling 

 loads, 490, in plowing, 491; trac- 

 tion of 491 ; principles of draft of 

 493, 494, 495, 496 ; equalizers for, 

 496, 499 ; In tread power. 500. 



Horse power, 27 ; measure of solar en- 

 ergy, 22 ; equivalent of, consumed I.i 

 melting Ice and in evaporating water, 

 30 ; of horses, 490, in hauling loads, 

 490, In plowing, 491; In tread 

 power, 500 : of engine. 530 : trans- 

 mission of by belts, 544. 



Hot box, 542. 



Hot tube, 529. 



Humus, 76 ; of arid and humid climates, 

 76 : loss from and need for In sandy 

 soils, 206 ; on sandy roads, 457. 



