THE MUMER'S MAGAZINE. 



4/3 



dressings in as wet ti state as possible, either by 

 the water-drill, or by mixinfj them with wetted 

 ashes, or other friable substances, and also having 

 this done as near sunset as possible. Even when 

 water cannot be added, it is very desirable that the 

 ashes should be used. It was in the last number 

 of the Journal of the Royal Agricultural Society 

 that Professor Yoelcker observed, when speaking 

 of tlie application of top- dressings, "I cannot re- 

 frain from observing that all artiHcial manures — 

 such as nitrate of soda, guano, or a mixture of 

 nitrate of soda and salt -should not only be first 

 passed through a fine sieve, but they should also be 

 mixed with three to five times their own weight of 

 fine red ashes, dry soil, or sand, before sowing 

 them broadcast by hand, or, v/hat is much more 

 convenient and better, by the broadcast manure 

 distributor. Chambers' or Reeves' dry manure 

 distributor cannot be too highly recommended for 

 sowing, in a most uniform and expeditious manner, 

 top-dressings of every description." 



I certainly seem to incline very strongly to the 

 opinion, that the maximum benefit in applying 

 cui)ic petre to grass, is obtainable by applying it 

 in solution. Some experiments of the late P. 

 Pusey on a small scale decidedly support this view 

 of the case {Jour.lRoy.Ar;. Soc, vol. xiv., p. 376.) 



The recently rej)orted iield experiments of Pro- 

 fessor Voelcker on top-dressing wheat, are valuable 

 on several accounts. They not only were 

 conducted with the careful accuracy of the chemi- 

 cal philosopher, but they tend to elucidate more 

 than one diflfjcult question to which I have just 

 alluded. In the opening sentences of his essay 

 he observes {Jour. Rorj. Ag. Soc, vol. xx., p. 386) : 



" There is no lack of experiments made with 

 guano, nitrate of soda, soot, shoddy, gas-water, 

 and other nitrogenized substances, which are occa- 

 sionally used as top-dressings upon wheat. Ex- 

 perience has shown that all these manures may be 

 used, with more or less advantage, for the wheat 

 crop ; and that, generally speaking, they are the 

 more efl'ective the more nitrogen they contain. 

 Thus Peruvian guano or nitrate of soda, which are 

 both very rich in nitrogen, are justly considered 

 more powerful wheat manures than soot or shoddy 

 — two materials much poorer in this element. 

 Whilst I consider the relative proportions of ni- 

 trogen in different fertilizers, intended to be used 

 for wheat or other cereal crops, to be an important 

 element in estimating the comparative commercial 

 and agricultural value of artificial manures, such 

 as Peruvian guano, nitrate of soda, or sulphate of 

 ammonia, I am of opinion that the form or state 

 of combination in which the nitrogen is contained 

 in the manure materially affects its efficacy. Any 

 one who has tried side by side nitrate of soda, 

 Peruvian guano, and shoddy, must have felt sur- 

 ]nised at the different degree of rapidity with which 

 the effects of these three fertilizers are rendered 

 perceptible in the field. I have noticed more than 

 once that, under favourable circumstances, the 

 effects of nitrate of soda became visible in the 

 course of three or four days in the darker green 

 colour and more luxuriant appearance of the young 

 wheat, whilst it took eight or ten days in the case 

 of guano to produce a similar effect. On wheat 



dressed with shoddy no apparent effect was pro- 

 duced even after the lapse of four or six weeks. 

 So slow is the action of the latter that a superficial 

 observer might well doubt the efficacy of shoddy 

 as a wheat manure, for it often produces no visible 

 improvement in the wheat crop, and it is only after 

 thrashing out the corn that it can be ascertained 

 that shoddy has had some effect upon the yield of 

 corn. These examples appear to indicate that ni- 

 trogen in the shape of nitric acid has a different 

 practical value from that which it possesses in the 

 shape of ammonia, and that it has again another 

 value in the form of nitrogenized organic matter. 

 It must be confessed that our knowledge of the 

 comparative efficacy of nitrogen, in its various 

 states of combination, is extremely limited, inas- 

 much as we scarcely possess any sufficiently accu- 

 rate and trustworthy comparative field experiments 

 which are calculated to throw light on this sub- 

 ject. As yet the sure foundation on which an ex- 

 plicit opinion as to the relative merits of nitrogen 

 — in the shape of nitric acid, ammonia, or organic 

 matter — can be given, is altogether wanting. It 

 is true the experience of practical men affords cer- 

 tain useful indications to the scientific ooserver, 

 but nothing more. In the absence of clear, un- 

 mistakable, and sufl^iciently extensive practical 

 evidence, no definite answer can be given to the 

 question so frequently addressed to the agricul- 

 tural chemist. Shall I apply nitrate of soda or 

 guano upon my wheat?'' 



As Professor Voelcker's top-dressings were ap- 

 plied to the wheat on the 22nd of March, 1859, 

 they do not serve to indicate at how late a period 

 in the spring such dressings may be applied. The 

 following table gives the manures applied by him 

 and the produce per acre of both seed and straw, 

 the first being given in bushels, the straw in tons 

 and cwts : Seed. Straw. 



Soil simple. ..V 27 .... 17 



2^ cwt. Peruvian guano 40 1-lOth... 1 3 



1 J cwt. nitrate of soda 38 .... 1 4 



ISOlbs. of nitrate of soda., \ ,^ ,, ,„*i i 

 , ,. ^l. r •10 0-lOths.. 1 4 



1 cwt. common salt J 



4 cwt. Proctor's wheat manure 393 • • • • 1 3 



6 cwt. ditto ditto 44 l-.5th . . 1 7 



Chalk marl 4 tons 27 16 



There are some recently reported trials by Mr. 

 Dove, of Eccles Newton, Kelso, which rather en- 

 courage us to hope that certain top-dressings may 

 be applied with advantage much later in the sea- 

 son than is usually the practice. In his trials 

 {Trcais. Hifjh. Society, 1S60, p. 229), the 

 dressings to the grass were generally applied on 

 the 13th of May. The following are the reported 

 results ; those described in italics, however, had 

 the dressings divided into three portions, a third 

 being applied on the 13th of May, the others on 

 the 27th of May and the 3rd of June, the cost 

 of each manure being £1 I7s. per acre, and the 

 produce given in tons and cwts. 



Tons. Cwts. 



Soil simple 1 4 



3 (^vt. guano 2 



3 Civt. yuano 1 15 



2 ('wt. nitrate of soda .... 1 17 

 2 Cwt. nitrate of soda .... I ) 9 



K K 2 



