The pots were disposed in a glazed case within a cold grapery,[7] and were watered when needful with pure water. The seeds sprouted duly, and developed into healthy plants. The plants served thus as tests of the chemical effect of carbonate of lime, of slaked lime, and of salt and lime mixture, on the peat. The guano pots enabled making a comparison with a well-known fertilizer. The plants were allowed to grow until those best developed, enlarged above, not at the expense of the peat, etc., but of their own lower leaves, as shown by the withering of the latter. They were then cut, and, after drying in the air, were weighed with the subjoined results. VEGETATION EXPERIMENTS IN PEAT COMPOSTS. KEY A - _Weight of crops in grammes._ B - _Comparative weight of crops, the sum of 1. and 2. taken as unity._ C - _Ratio of weight of crops to weight of seeds, the latter assumed as unity._ -------------------------------------------+---------------+----+------- _Nos._ _Medium of Growth._ | A | B | C -------------------------------------------+---------------+----+------- 1 } | 1.61} | | 2 } Peat alone. | 2.59} 4.20 | 1 | 2-1/2 | | | 3 } | 14.19} | | 4 } Peat, and ashes of grass, | 18.25} 32.44 | 8 | 20-1/2 | | | 5 } | 18.19} | | 6 } Peat, ashes, and carbonate of lime, | 20.25} 38.44 | 9 | 25-1/2 | | | 7 } | 21.49} | | 8 } Peat, ashes, and slaked lime, | 20.73} 42.22 | 10 | 28-1/2 | | | 9 } | 23.08} | | 10 } Peat, ashes, slaked lime, and salt, | 23.34} 46.42 | 11 | 30-1/2 | | | 11 } | 26.79} | | 12 } Peat, ashes, and Peruvian Guano, | 26.99} 53.78 | 13 | 35-1/2 -------------------------------------------+---------------+----+------- Let us now examine the above results. The experiments 1 and 2, demonstrate that the peat itself is deficient in something needful to the plant. In both pots, but 4.2 grammes of crop were produced, a quantity two and a half times greater than that of the seeds, which weighed 1.59 grammes. The plants were pale in color, slender, and reached a height of but about six inches.