124 



On the Nitrate of Soda, 



so differ from the other three, but they agree with them in containing 

 nitrogen in the form of nitric acid. IS^itrogen appears, then, to be the 

 active principle of the five substances. Dr. Liebig, in proving the 

 efficacy of ammonia as a manure, has shown the necessity of nitrogen 

 for forming the most nutritious part of our vegetable food, such as 

 gluten, which nitrogen again appears as a most essential element of all 

 animal frames. It is possible, however, that where a large portion of 

 nitrogen is applied to wheat-crops as manure, gluten may be pro- 

 duced in excess, and that the wheat may be deficient on the other 

 hand in some essential element, such as lime. According to Dr. 

 Liebig's principles, we should be able to remedy this defect by 

 applying lime at the same time in such a state as would be readily 

 absorbed by the plant. I mention this, however, rather as an exem- 

 plification of those principles than as a practical suggestion. But 

 having been led almost too far into this subject, I will only express 

 the hope, that men of science who are competent to do it justice may 

 be disposed to assist us by investigating the operation of manures and 

 the food of plants. I cannot but think that we are on the eve of 

 important discoveries in this department of theoretical agriculture. 

 With regard to the practical use of the manure, to which you have 

 called our attention, its effects in this neighbourhood have certainly 

 borne out the doubts which you expressed. It seems to me that we 

 should all try it, since it is of undoubted efficacy in many cases, but not 

 on a large scale at first, unless we know that it has acted well on 

 the particular soil and crop we wish to benefit, because its cost is consi- 

 derable, and it sometimes fails altogether. 



Yours, my dear Sir, very truly. 



Ph. Pusey. 



Fusey, Nov. 6, 1840. 



To D. Barclay, Esq. 



E J tract of a Letter from the Earl of Zetland. 



Upteatham^Nov. 3rd, 1840. 



My dear Barclay, 

 I HAVE received a letter from Mr. Pusey, begging me to communi- 

 cate any further information I may possess on the use of Nitrate of 

 Soda, for the use of the Journal. I have answered him that I was 

 about to write to you on the subject, and that I conceived he would 

 be satisfied to have my observations communicated through you. I 

 now enclose you some remarks made by my bailiff, John Alderson. 

 In addition to his information I have little worth communicating, 

 because I have not made accurate measurements; and having sown 

 whole fields with the nitrate, I have not the means, by my own ob- 

 servation, of making comparisons. I had two fields of wheat at 

 Marske sown with nitrate of soda. Owing to the very bad seed-time 

 last year these two fields were not sown with wheat till January. The 

 nitrate was pat on about the 13th of May. Both these fields were 



