Sulphur in plants, 66. Sun, work of in making soils, 32, 34. Sunlight, and the farmer, 5. necessary for leaf work, 110, 111, 112. Superphosphates, 198. Swamp muck, 30. Sweet clover, 190. Sweet potato roots, 13. soils, 28, 160. Sweet potatoes, 5. Sylvinite, 199. Systems of cropping, 119. Tankage, 194. as fertilizer, 194. nitrogen in, 194. phosphoric acid in, 194. Temperature of soil, 57. Tendrils, plants climb by, 122. Testing seeds, 75. Testing soils for water, 162. for plant food, 215. Texture of soils, 37, 143, 150. Thinning fruit, 137. Thistle, 6. Thistle family, 86. Thomas slag, 198. as fertilizer, 198. phosphoric acid in, 198. Tillage and plant food, 67. and fertility, 150. Time to begin this study, 3. Time to plow, 98. Tobacco soils, 27. Tomato soils, 161. Tools, 5. and the farmer, 5. Transpiration, the fact, 110. amount of, 111. Transplanting, 87. machines, 89. Truck of plow, 95. Truck soils, 27, 28, 29, 161. Tubercles on roots of legumes, 68, 144. Turnip, 6. Type soils, 26. Under drains, 237. advantage of, 237. Underground stems, 121. Value of knowledge of flowers, 134. Vegetables, roots, 13, 14, 15. soil for, 28. Ventilation of soils, 68, 142. necessary for germination, 73. necessary for root growth, 21, 22, 23. necessary for fixation of nitrogen, 144. Water, absorption of by soil, 40, 43, 46, 142. amount used by plants, 40. capillary, 49, 153. evaporation of, 54, 155. free, 48, 153. film, 50. ground, 48. importance of to plants, 39. percolation of, 41. relation of soils to, 39. standing, 48. work of in making soils, 33, 35. Water and the farmer, 5. Water in plants, 65. Watering house plants, 51. Watermelon soils, 28, 161. Weeders, 167. Weeds, 54. how they injure crops, 54, 92. how to kill, 119. waste soil water, 54. Wheat soils, 29, 30. water used by, 40. Wheel hoes, 168. White hellebore, 117. Wind pollination, 132. Work of roots, 9, 10, 15. Work of sun in making soils, 32, 34. air in making soils, 36. animals in making soils, 37. moving ice in making soils, 35. moving water in making soils, 33, 35. plants in making soils, 36. rain in making soils, 33. Wood ashes, 199. Wool waste as fertilizer, 195. * * * * * End of Project Gutenberg's The First Book of Farming, by Charles L. Goodrich