HKB
Pots 5 and 6 contained each 270 grammes of peat, 10 grammes of ashes, and 10 grammes of carbonate of lime.
Pots 7 and 8 contained each 270 grammes of peat, 10 grammes of ashes, and 10 grammes of slaked (hydrate of) lime.
Pots 9 and 10 contained each 270 grammes of peat, 10 grammes of ashes, and 5 grammes of lime, slaked with strong solution of common salt.
Pots 11 and 12 contained each 270 grammes of peat, 10 grammes of ashes, and 3 grammes of Peruvian guano.
In each case the materials were thoroughly mixed together, and so much water was cautiously added as served to wet them thoroughly. Five kernels of dwarf (pop) corn were planted in each pot, the weight of each planting being carefully ascertained.
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.
Nos. 3 and 4 make evident what are some of the deficiencies of the peat. A supply of mineral matters, such as are contained in all plants, being made by the addition of ashes, consisting chiefly of phosphates, carbonates and sulphates of lime, magnesia and potash, a crop is realized nearly eight times greater than in the previous cases; the yield being 32.44 grammes, or 20-1/2 times the weight of the seed. The quantity of ashes added, viz.:--10 grammes, was capable of supplying every mineral element, greatly in excess of the wants of any crop that could be grown in a quart of soil. The plants in pots 3 and 4 were much stouter than those in 1 and 2, and had a healthy color.