122 



On the Nitrate of Soda. 



Dough. Bread, 



lbs. oz. lbs. oz. 



9 lbs. of nitred flour gave . . . ]3 8 11 6 



9 lbs. of unnitred flour .... 13 10 11 10 



It appears that in this trial the nitred flour absorbed 2 oz. less of water 

 than the other ; but this difi"erence is not sufficient to account for its 

 inferior yield of bread, since that deficiency amounted to 4 oz. Though 

 even this latter diff'erence does not appear large, it takes two loaves from 

 every hundred. It may be, however, that as much nourishment is con- 

 tained in the smaller number of loaves. The bread of the nitred wheat, 

 I must say, seemed the best and most agreeable, resembling the common 

 white bread made in the south of Spain, the wheat of which country 

 abounds, I believe, in gluten. Still, with all these abatements, the 

 nitrate appears to be a very promising manure ; and fortunately we need 

 not apprehend that, as with bones and with some other artificial manures, 

 the increase of its use should so raise its price as almost to absorb 

 the profit of its employment ; for the supply of it from the extensive 

 beds which lie near the surface in Peru must be as inexhaustible, for 

 centuries at least, as that of coals. This ample supply, as well as its easy 

 carriage, increase its importance, and render it the more desirable that 

 we should ascertain the causes of its success and its failure. At present 

 the nitrate appears most capricious in its operation ; but it is not, of 

 course, Nature who is variable, but we who are ignorant. That it has 

 a strong power over vegetation is certain : why it should have failed 

 here, on the light soils, I cannot discover ; possibly the dryness of the 

 late summer may have checked its action. The same drought, I have 

 been told, has occasioned a coat of common dung, laid on a grass-field 

 in this neighbourhood, to produce no eflect. On the grass-lands south 

 of Newbury wood-ashes are an established dressing; but they, too, I am 

 told, have been known to fail in dry weather. All top-dressings, I believe, 

 require to be followed by rain. Our light land suffers particularly in 

 the absence of rain : and the barley sometimes burns the soonest where 

 the ground has the most dung. I shall mention as a caution, that the 

 nitrate has actually produced this eff'ect in a case which has come within 

 my own knowledge. One of my neighbours dressed some wheat and 

 barley lying near each other on a free loam near Abingdon, with 140 lbs. 

 of the nitrate per acre, in the middle of May. The wheat acquired the 

 dark green, but was not benefited. The barley showed no immediate 

 eff'ect, but in the end suffered serious injury. On the part which had 

 been dressed the straw did not reach more than half its proper height, the 

 ear was blighted, the crop in fact was completely burned up. In the case 

 of Sir R. Throckmorton's wheat, the land may have been too high in 

 condition already ; for there are limits, of course, beyond which the pro- 

 duce of a given soil cannot be brought by any manure, or any quantity of 

 it. If a dressing of dung raises the yield of an acre from 32 to 40 bushels, 

 no practical man will expect that a double dressing will produce 48 

 bushels, or that three times as much dung will give 56 bushels. It is, I 

 think, very likely that the land at Buckland has been so highly farmed as 

 to bring its fertility to the utmost point, so that the nitrate would be in 

 the same relation to the soil as a third dressing of dung. Pbssibly this 



