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The reclamation of salt patches for the purpose of bringing 

 them under cultivation rests upon three chief points : 



1. Draining to carry away the excess of salt and preventing 



fresh amounts being drawn up from the subsoil below. 

 This is the one efficacious and radical way of reclaim- 

 ing salt patches of any sort. The underdrainage in 

 deep hollows is not only often impracticable but is 

 generally costly. Besides, there is often found, in con- 

 junction with these noxious salts, other chemicals of high 

 fertilising value, such as sulphates, nitrates, phosphates 

 of potash and soda, which would run away to waste in 

 the drains and be lost to the soil. Should this be the 

 case, it would in many instances be advisable to alter the 

 poisonous substances in the soil and neutralise their 

 injurious effect, so as to place them beyond the means 

 of causing any injury, and this can be affected by 



2. Neutralising the corrosive salts by means of chemicals 



and changing their nature into that of the more 

 innocuous ones. To best effect this, some cheap sub- 

 stance, which by chemically reacting on the sodium 

 carbonate would transform it into an inactive salt, is 

 necessary, and is readily found in gypsum or sulphate 

 of lime, which by a mutual shuffling or interchange 

 of the basic and acidic elements, become respectively 

 carbonate of lime or limestone and sulphate of soda or 

 Glauber's salt. The gypsum, moreover, renders 

 insoluble the humus taken up and dissolved by the 

 carbonate of soda, and thus retains it in the soil. 



3. The injurious substances having been neutralised, it is 



essential to reduce the surface evaporation which 

 would tend to accumulate on the surface layers the 

 soluble salts sucked up by means of capillary attraction. 

 This is best effected by means of deep cultivation, fre- 

 quently repeated, and by growing crops which root 

 deeply and cover the ground, as well also as salt-loving 

 plants such as plants of the cabbage and of the beet 

 tribe or such plants as asparagus, saltbushes, and a 

 variety of others. By such means the successful and 

 profitable cultivation of the soil would, in mild cases, 

 be quite feasible. 



Besides that of neutralising the injurious effects of the 

 carbonate of soda, gypsum has a correcting effect on the physical 

 conditions of the soil, which often becomes glutinous and forms a 

 clayey hardpan. It coagulates the glutinous substance formed by 

 the carbonate and destroys the puddled condition of the clay, thus 

 enabling the roots to penetrate and the waters to drain through 

 such soils. 



