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The efficacy of all fertilisers is due to the material substances which 

 enter into their combination ; and as many of the usual components of 

 manures have a specific effect upon vegetation, it cannot be reasonably 

 expected that Q-as-lime, abounding in combinations of lime should pro- 

 duce the same results in the field as those which a phosphatic or ammo- 

 niacal manure is capable of producing. 



A glance at the preceding analysis shows plainly that gas-lime acts 

 as a fertiliser solely in virtue of the lime compounds which occur in it. 

 Like quicklime, it discharges the four following important functions : 

 (1) Gras-lime exercises a beneficial mechanical effect upon land, by ren- 

 dering stiff, heavy clay land, more porous, friable, and consequently 

 better adapted for cultivation, and by consolidating, on the other hand, 

 light, sandy soils. (2) It supplies food to plants. All our cultivated 

 plants on burning furnish ashes, containing a good deal of lime, which 

 is essential to the healthy development of all vegetable produce. As 

 plants have not the power of generating lime, it is clear either the soil 

 upon which they are grown or the manure which is put upon it must 

 contain a sufficient amount of this constituent, so necessary for the very 

 existence of all plants. Gas -lime not only supplies lime to plants, but 

 also sulphuric acid, a combination not present in any quantity in quick- 

 lime. For leguminous crops, such as Peas, or Beans, for Clover, and 

 other crops specially benefited by sulphate of lime or gypsum. Gas-lime 

 when obtainable, as is generally the case, at a trifling expense is cer- 

 tainly preferable to quicklime as a manure, (3) Gas-lime, in virtue of 

 its alkaline properties, exercises a beneficial effect upon the organic 

 matters in the soil. In this respect its action is similar to that of quick- 

 lime. Both facilitate the destruction of organic matters, the remains 

 of previous crops, and their conversion into plant food. (4) Gas-lime, 

 like quick-lime, has the power of unlocking, so to say, the naturally un- 

 available mineral stores of plant food in the soil. In many soils, but 

 more especially in clay land, we find portions of granite and other 

 minerals from which clay has been originally produced. These minerals 

 are the chief sources from which the necessary amount of alkalies re- 

 quired by plants is furnished. But as their decomposition proceeds 

 slowly, a long time must pass before potash and soda can be rendered 

 soluble, or made available for the use of the plants. Gas-lime, like 

 quicklime, materially hastens this decomposition, and thus produces an 

 effect similar to that of a prolonged fallow. 



Its Uses. 



These remarks on the functions of gas-lime in relation to vegetable 

 life at once point out the crops which are benefited by its applicati n, 

 and in a special manner, the kind of land upon which it produces the 

 most striking results. 



The crops which are particularly benefited by Gas-lime are : Clover, 

 Sainfoin, Lucerne, Peas, Beans, Vetches, and Turnips. It is also a 

 most useful fertiliser for permanent pasture, especially if the land is na- 

 turally deficient in lime. On natural grasses the best farmyard manu re 

 often produces little improvement until a dressing of lime, marl or Gas- 

 lime has been applied. The latter more particularly destroys the coarser 



