PROCEEDINGS OF THE FARMERS' CLUB. 345 



have been for many centuries. Irrigation is a mode of applying the very 

 weakest of liquid enricliers on an extensive scale to grass lands. And all 

 farmers practicing it have a mode of accounting for its fertilizing effects. 

 Davy in his explanation imagined that a winter flooding protected the grass 

 from the evil effects of frost. He examined with a thermometer certain 

 water meadows, and discovered that the temperature of the earth was 12' 

 higher than tlie water at the surface, on a cold March morning. He also 

 remarked that waters which breed the best fish arc the best for watering 

 meadows. If river water is used, and it contains gypsum, whicli it inva- 

 riably does if the water is hard, it will be found highly fertilizing to 

 meadows, as all grasses abound in this salt. If one part of gypsum is 

 contained in two thousand parts of water, and every piece of land a yard 

 square absorbs eight gallons, then every flooding leaves a little more than 

 100 lbs. of gypsum (or sulphate of lime) on the soil, which is a quantity 

 fully equal to that spread in the powdered form by farmers upon their 

 clover, lucerne, and other crops. The generality of river waters contain 

 about twenty-six parts of vegetable and animal remains in a thousand 

 parts, consequently every soaking we give the land with such water we 

 add two tons to the acre of vegetable and animal matters, and as we usually 

 flood them five times a year, we add ten tons of organic matter to the acre. 

 River water in ten thousand parts after its suspended matters have sub- 

 sided contains: 



^Muriate of soda 0.02 



Carbonate of lime 1.90 



Organic matter , 0.02 



Sulphate of lime 0.75 



The water of inland seas contain more of the above matters than rivers, 

 and consequently are more valuable for irrigating purposes. 



If a quart of river water contains a half a grain of ammonia, then a 

 field of eighty thousand square feet must receive annually upwards of one 

 hundred and sixty pounds of ammonia, or one hundred and thirty pounds 

 of nitrogen. This is far more nitrogen than is contained in 2,900 lbs. of 

 hay, or 2,700 lbs. of wood. 



Another reason why liquids are more useful than solids is that the former 

 contains the largest portion of its ammonia in the state of salts, in which 

 form it has lost its volatility, and when presented in this shape not the 

 minutest quantity of ammonia is lost to the plants, because it is entirely 

 dissolved by water and enters by their spongioles. 



If you desire to raise asparagus, sea kale, or any other salt loving plant 

 in large quantities, irrigation with salt water will be found advantageous 

 as it contains in every thousand parts, 



25 of common salt. * 



4| sulphate of soda. 



1| muriate of potash. 



5^ muriate of magnesia. 



1| sulphate of lime or gypsum. 



Tlie sea by its continued evaporation spreads over the entire surface of 

 the earth its salts, which are furnished to the roots of all vegetable pro- 

 ductions by being carried to them by the rain, through the medium of the 



