52. A straight knife coulter 96

53. An iron beam-plow with rolling coulter and double
clevis 96

54. A rolling cutter-harrow 97

55. Spring-toothed harrows 97

56. Spike-toothed harrows 104

57. A coulter-toothed harrow 104

58. A plank harrow 105

59. To show transpiration 108

60. Amount of transpiration 109

61. To show that growing leaves contain starch 114

62. To show that starch disappears from the leaf when
the plant is placed in the dark 114

63. To show that sunlight is necessary for starch-making
by leaves 115

64. To show that chlorophyl is necessary for starch
formation in the leaf 115