THE FARMERS- REGISTER. 



465 



"The employment of animal manure in the cultiva- 

 tion of fiiaiii, and the vcgetabk's vviiich serve ior 

 foililer to cattle, is the most convincing proof that 

 the nitro2;en of vegetables is derived from anunonia. 

 The qnantiiy of gluten in wheat, rye, and barley, 

 is very dilierent ; these kinds of grain also, even 

 when iipe, contain this compound of nitrogen in very 

 different proportions. Proust found French wheat to 

 contain 12-5 per cent, of gluten ; Vogel found that the 

 Bavarian contained 2 1 per cent. ; Davy obtained 19 

 per cent, from winter, and 24 from summer wheat ; 

 from Sicilian 21, and from Barbary wheat 19 per cent. 

 The meal of Alsace wheat contains, according to 

 Bou.ssingault, 17.3 per cent, of gluten; that of wheat 

 grown in the '• Jardin des Plantes" 26.7, and that of 

 winter wheat 3 33 per cent. Such great difierences 

 must be owing to some cause, and this we find in the 

 ditferent methods of cultivation. An increase of ani- 

 mal manure gives rise not only to an increase in the 

 number of seeds, but also to a most remarkable dif- 

 ference in the proportion of the gluten which they 

 contain. 



" Animal manure, as we shall aftenvards show, acts 



ihj by the formation of ammonia. One hundred parts 

 of wheat grown on a soil manured with cow-dung (a 

 manure containing the smallest quantity of nitrogen,) 

 alforded only 11.95 parts of gluten, and 64.34 parts of 

 amylin, or starch ; whilst the same quantity, grown 

 on "a soil manured with human urine, yielded, the 

 maximum of gluten, namely 35.1 per cent. Putrefied 

 urine contains nitrogen in the forms of carbonate, 

 phosphate, and lactate of ammonia and in no other 

 form, than that of ammoniacal salts. 



" Putrid urine is employed in Flanders as a manure 

 with the best results. During the putrefaction of 

 urine, ammoniacal salts are formed in large quantit}', 

 it may be said exclusively; for under the inlluence 

 of heat and moisture urea, the most prominent ingre- 

 dient of the urine, is converted into carbonate of am- 

 monia. The barren soil on the coast of Peru is ren- 

 dered fertile by means of a manure called guano, 

 which is collected from several islands on the South 

 Sea.* It is sufficient to add a small quantity of guano 

 to a soil, which consists oiily of sand and clay, in 

 order to procure the richest crop of maize. The soil 

 itself does not contain the smallest particle of organic 

 i matter, and the manure employed is formed only of 

 urate, phosphate, oxalate, and carbonate of ammonia, 

 together with a few earthy salts." — (pp. 136, 137.) 



" The urine of men and of carnivorous animals con- 

 tains a large quantity of nitrogen, partly in the form 

 of phosphates, partly as urea. Urea is converted du- 

 ring putrefaction into carbonate of ammonia, that is 

 to say, it takes the form of the very salt which occurs 

 in rain-water. Human urine is the most poweiful 

 manure for all vegetables contaiiiing nitrogen ; that 

 of horses and horned cattle contains less of this ele- 

 ment, but infinitely more than the solid excrements of 

 these animals." — (p. 138.) 



" The solid excrements of animals contain com- 

 paratively very little nitrogen, but this could not be 

 otherwise. The food taken by animals supports them 

 only in so far as it offers elements for assimilation to 

 the various organs, which they may require for their 

 increase or renewal. Corn, grass, and all plants, 

 without exception, contain azotized substances. The 

 quantity of food, which animals take for their nourish- 

 ment, diminishes or increases in the same proportion, 

 as it contains more or less of the substances contain- 



* " The guano, which forms a stratum of several feet 

 in thickness upon the surface of these islands, consists 

 of the putrid excrements of innumerable sea-fowl that 

 remain on them during the breeding season. 



" According to Fourcroy and Vauquelin it contains a 

 fourth part of its weight of uric acid, with ammonia 

 and potash." 



Vol. 1X.-42 



ing nitrogen. A horse may be kept alive by feeding 

 it with potatoes, which contain a veiy small quantity 

 of nitrogen ; but life thus supported is a gradual 

 starvation ; the animal increases neither in size nor 

 strength, and sinks under every exertion." — (p. 139. J 



The deductions and priiciicrii apfilicalioiis to be 

 made from Liebiix's cliemical lacts in regard to iii- 

 Iroiren and aninionia are so imporiarit, thai we 

 may be excused from quoting siill more at length. 



" As it is evident that the nitrogen of the plants 

 and seeds used by animals as lood must be employed 

 in the process of assimilation, it is natural to expect 

 that the excrements of these animals' will be deprived 

 of it, in proportion to the perfect digestion of the lood, 

 and can only contain it when mixed with secretions 

 from the liver and intestines. Under all circumstances, 

 they must contain less nitrogen than the food. When, 

 therefore, a field is manured with animal excrements, 

 a smaller quantity of matter containing nitrogen is ad- 

 ded to it than has been taken from it in the form of grass, 

 herbs, or seeds. By means of manure, an addition 

 only is made to the nouiishment which the air supplies. 



In a scientific point of view, it should be the care 

 of the agriculturist so to employ all the substances 

 containing a large proportion ol nitrogen which his 

 !aim atfbrdsin the form of animal excrements, that 

 they shall serve as nutriment to his own plants. This 

 will not be the case unless those substances are pro- 

 perly distributed upon his land. A heap of manure 

 lying unemployed upon his land would serve him no 

 more than his neighbors. The nitrogen in it would 

 escape as carbonate of ammonia into the atmosphere, 

 and a mere carbonaceous residue of decaying plants 

 would, after some years, be found in its place. 



All animal excrements emit carbonic acid and am- 

 monia, as long as nitrogen exists in them. In every 

 stage of their putrefaction an escape of ammonia 

 from them may be induced by moistening them with 

 a potash ley ; the ammonia being apparent to the senses 

 by a peculiar smell, and by the dense white vapor 

 which arises when a solia body moistened with an acid 

 IS brought near it. , This ammonia evolved fiom ina- 

 nme is imbibed by thd soil either in solution in water, 

 or in the gaseous form, and plants thus receive a larger 

 supply of nitrogen than is afforded to them by the 

 atmosphere. 



But it is much less the quantity of ammonia, yielded 

 to a soil by animal excrements, than the form in whicU 

 it is presented by them, that causes their great influ- 

 ence on its fertility. Wild plants obtain more nitro- 

 gen from the atmosphere in the form of ammonia than 

 they require for their growth, for the water which 

 evaporates through their leaves and blossoms, emits, 

 after some time, a putrid smell, a peculiarity possessed 

 only by such bodies as contain nitrogen. Cultivated 

 plants receive the same quantity of nitrogen from the 

 atmosphere as trees, shrubs, and other wild plants ; 

 but this is not sufficient for the purposes of agriculture. 

 Agriculture differs essentially from the cultivation of 

 forests, inasmuch as its principal object consists in 

 the production of nitrogen under any form capable 

 of assimilation ; whilst the object of forest culture is 

 coufinea principally to the pioduction of carbon. All 

 the various means of culture are subservient to these 

 two main purposes. A part ordy of the carbonate of 

 ammonia, which is conveyed by rain to the sod, is 

 received by plants, becau.'^e a certain quantity of it 

 is volatilized with the vapor of water; only that por- 

 tion of it can be assimilated which sinks deeply into 

 the soil, or which is conveyed directly to the leaves 

 by dew, or is absorbed from the air along with the 

 carbonic acid. 



Liquid animal excrements, such as the urine with 

 which the solid excrements are impregnated, contain 

 the greatest part of their ammonia in the state of 

 salts, in a form, therefore, in which it has completely 

 lost its volatility when presented in this condition ; 



