or in little "books" which contain about twenty- five or fifty strips of the paper, about 

 one-half inch wide and two or three inches long. This is the most convenient form in 

 which to have the test paper. If the sheets are purchased, they may be cut into strips 

 the size of those in the books and placed in a clean, dry, wide-mouthed, well-corked 

 bottle, to keep them from acid fumes. When this paper comes in contact with an 

 acid it turns red. 



A very simple method and a very satisfactory one, in our experience, of applying 

 the test, is to make a ball of damp soil, break it open and lay the paper on the broken 

 surface, then squeeze the parts together again and allow to stand for from three to five 

 minutes. On opening the ball, if the paper has turned red, we may conclude that the 

 soil is sour, and in need of lime. It is apparent that the hands must be free from acid, 

 and the soil damp enough to press into shape. Unless the soil is very dry, we have 

 usually found, that by getting a sample three or four inches below the surface, there 

 was enough moisture to answer the purpose. 



Lime has two main types of action; it supplies basic material which is very necessary 

 for the soil, and it impfoves the physical condition of both sands and clays. The 

 necessity for a base is very definitely marked, for, in its absence the soil becomes acid and 

 is "sour." Such soil is not well suited to plant growth and will not carry luxuriant 

 crops. Certain weeds, however, grow well, notably sorrel and Scouring Rush or Horse 

 tail. The sourness is not only inimical to plants, but also to micro-organisms, and the 

 differences seen in vegetation are probably no greater than those existing in the nature 

 of the organisms that live in the two classes of soils. Just as certain plants naturally 

 predominate in sour soils, so also do certain micro-organisms, and, apparently, some of 

 these at least, prevent the growth of the most desirable forms. Thus a soil may contain 

 an abundance of organic matter; but, if sour, there will be little or no nitrogen in the 

 form of nitrates, because the nitrifying organisms required for their production cannot 

 develop under the existing conditions. 



The alteration in physical condition brought about by liming is probably due to 

 the binding together of the small particles of clay, causing them to act like soils made up 

 of larger particles. Or, in other words, the deflocculated or sticky clay is converted 

 into the flocculated or friable form. The coarse particles of sandy soils are also bound 

 together through the action of the lime and the soil becomes firm and does not dry out 

 so readily. 



In addition to correcting acidity and improving physical state, it is probable that 

 lime is absorbed from its solution by certain constituents of the soil, and displaces some 

 of the substances previously absorbed. In this way, lime causes the liberation of a 

 certain amount of potash from the soil so that a dressing of lime may to some extent 

 take the place of an application of potash. When potash is so scarce as it is at the 

 present time, this is an important point. 



Taking into consideration all the important functions of lime in the soil and the 

 fact that our soils are steadily losing their lime and that none of our farm crops will grow 

 in an acid soil, it is evident why the application of lime is so important. 



Lime may be purchased in the form of quick-lime, hydrated and air-slaked lime, 

 and limestone dust. Hydrated lime is simply the quick-lime slaked, screened and 

 bagged. The air-slaked material is the quick-lime that has slaked without the direct 

 addition of water. It differs from the hydrated lime in that it has taken up some carbon 

 dioxide from the air and part of the lime has passed back into the carbonate condition. 

 Thus quicklime is the oxide of lime (CaO), the hydrated, the hydroxide of lime (Ca(OH 2 ) 

 the air-slaked, a mixture of the hydroxide and carbonate of lime (Ca(OH 2 ) and (CaC0 3 ), 

 and the limestone dust, the carbonate of lime (CaCOs). 



Gypsum, or land-plaster, sulphate of lime (CaS0 4 ), has all the good effects of lime 

 in the soil, excepting that it will not neutralize acid. It is more soluble than the other 

 forms of lime and may be applied at a much less rate per acre. 



When considering which of the above forms should be applied, it is well to remember 

 that the fresh lime hastens the decay of organic matter. On soils of free aeration where 



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