0;^ the Failure of the Red Clover. 329 



phosphoric acid — so that, if the analysis had contained only '001 

 per cent., it would have contained 27 lbs. ; nay, if it had contained 

 •0005, it would have contained 13i lbs., which is nearly sufficient, 

 not only of phosphoric acid for the red clover, but which would 

 also be a sufficient quantity of chlorine, sulphuric acid, magnesia, 

 and soda, for either a crop of barley, rye-grass, or wheat. This 

 shows that even the analyses of soils given by Professor Liebig 

 are not sufficiently minute, although they exhibit the thousandth 

 part per cent, of the substance analysed; yet, before it can be 

 asserted that any soil is deficient in alumina, soda, sulphuric acid, 

 or magnesia, chemists must, owing to the small quantity of matter 

 required in so large a mass, give us less than one-half of the 

 decimal parts afforded in those given by Professor Liebig. In 

 fact, before it could have been predicated whether the clover on 

 this soil had failed for the want of alumina, it must have been 

 ascertained whether the soil even contained '0000 11 per cent, of 

 that earth. 



But in addition to the positive evidence afforded by the com- 

 parison of the two analyses of the soils that there is no exhaustion 

 of the food of the clover, we have the high authority of Professor 

 Liebig, who says, *' In some neighbourhoods clover will not thrive 

 till the sixth year, in others not till the twelfth ; flax in the second 

 or third year. All this depends on the chemical nature of the 

 soil ; for it has been found by experience that, in those districts 

 where the intervals at which the same plants can be cultivated 

 with advantage are very long, the time cannot be shortened even by 

 the use of the most powerful manures. The destruction of the 

 peculiar excrements of one crop must have taken place before a 

 new crop can be produced." — Chemistry applied to Agricul- 

 ture, p. 1 57. 



Indeed, Mr. Legard himself almost proves that its failure can- 

 not on the chalk wolds be ascribed to the want of any ingredient 

 of the clover, when he says " that for a period of eighteen years 

 he has used bones to the turnip-crops at the rate of 2 quarters 

 per acre, to the clovers rich farm-yard dung 10 tons per acre, 

 and to the wheat-crops rape-dust at the rate of 12 bushels per 

 acre, and that the clover-crops have been consumed on the ground 

 by sheep." Surely, if land be manured in this way, no exhaustion 

 of the soil can take place : and upon the magnesian limestone it 

 is scarcely possible that exhaustion of any specific ingredient can 

 be the cause of failure, because it is the custom to sow beans upon 

 these '^clover-sick" lands, wherever the soil is not very shallow; 

 and, if a good crop of beans can be grown on the same lands, it 

 follows that certain fixed ingredients must have been present in 

 the soil ; for beans contain as much potash, soda, magnesia, alu- 

 mina, and silica, as red clover, but a little less gypsum, phosphoric 



VOL. III. z 



