generally coarse, and with very little value as a feeding stuff. The 

 action of lime on tnese S'nls is to neutralise these organic acids and 

 prevent their formation, to sweeten the soil and promote the growth 

 of the line and nutritive grasses and to kill the coarse scrub. It 

 decomposes organic matter in the soil, bringing it into a in >re 

 soluble state and lit for the plants to absorb. 



BIOLOGICAL ACTION OF LIMK. 



This is one of the most important actions in the soil of lime, 

 which is one of the most active agents in the process of nitrifica- 

 tion. Its presence enables the micro-organisms in the soil to 

 decompose and convert the nitrogenous compounds into nitric acid, 

 which combines with the lime, the lime holding the nitric acid in 

 readiness for the use of the plants. I have already shown that 

 aicidity stops the process of nitrification, and may even cause the 

 reverse process of denitrification. I have also stated that too great 

 an alkalinity will also stop nitrification, and care must be taken that 

 not too great an alkalinity is created in the soil. In the case of over 

 liming the best cure is farmyard manure. 



GYPSUM, 



This salt of lime acts much in the same way as lime. It de- 

 composes the insoluble compounds of potash, setting them free 

 and making them available to the plants. It absorbs and fixes 

 ammonia in the soil. It promotes nitrification. When super- 

 phosphates are used, the soil always receives a certain amount of 

 gypsum, as it is one of the largest component parts of superphos- 

 phates. 



The crops that are most benefited by lime are the cereals, more 

 especially barley, and clover, potatoes, turnips and mangolds. 

 The quantity that it was usual to apply unde the old method of 

 liming was from four to six tons per acre every 12 to 14 years. 

 It is now, h nvever, considered more economical to apply one 

 to two tons every three or four years. Lime should be lightly 

 harrowed in. 



SPECIAL MANURES. 



These will be best treated upon when specifying the manures 

 for the different crops. Special manures should contain potash, 

 phosphoric acid and nitrogen in some form. 



There are a great many special manures made and sold 

 as such. Some of these, I am afraid, are only special in name, 

 with very little speciality in their nature. There are certainly 

 some special manures that are all it is professed for them, made by 

 linns who not only make manures, but wish to make a name 

 for themselves also ; while there are others, and those in large 

 numbers, whose sole aim is how to make, and how to 

 increase their profits at the expense of farmers. Why buy 

 these special manures ? The farmer who does so trusts blindly to 

 what the manufacturer tells him, and throws over his own judgment. 



