234 



NEW ENGLAND FARMER, 



sepa- 

 You 



DANA'S PRIZE ESSAY ON MANURES. 



[Continued.) 

 Let us Bnalj'ze a plant. Do not be startled at 

 the word. To analyse, means to separate a conn- 

 poiinj substance into the several substances which 

 form it. This may be done by a vciy particular 

 and minute, or by a more general division. It 

 may be done, for our present purpose, by separa- 

 ting the several substances of a plant into classes 

 of compounds. Y'ou are already chemist enough 

 to undertake this mode of analysis ; in truth, you 

 have already done it again and again. For our 

 purpose, the ancient chemists had a rery good di- 

 vision of all matter into four elements — fire, air, 

 earth, and water. Now, by fire you separate 

 plants into the other three elements. You are, 

 reader, though perhaps you do not know it, some- 

 what of a practical chemist. Whenever you have 

 burned a charcoal-pit, what did you ? You 

 rated the wood into air, water, and earth, 

 drove off by heat or fire the airy or volatile parts 

 of the plant ; you left its carbon or coal : if you 

 had burnt this, you would have left ashes. Now 

 these ashes are the earthy parts of plants. If you 

 burn a green stick of wood, you drive off first its 

 water and volatile parts, which fortn soot. You 

 burn its carbon, and leave its ashes or salts. So 

 that by simply burning, you reduce the substance 

 or elements of plants to water, carbon, salts. 



AH plants, then, without exception, contain the 

 several substances in our list above, as water, car- 

 bon, and salts. To apply this knowledge to ma- 

 manure, we must say a word on the form in which 

 some of these, which we call the elements of 

 plants, exist in them. The sap is water; it holds 

 dissolved in it some salts of the plant. This sap 

 or juice forms a pretty large proportion of the 

 roots — say seventyfive to eighty parts in one hun- 

 dred of potatoes, turnips, beets, &c. This may be 

 called the water of vegetation. If we dry beet- 

 root, or any other plant, we merely drive ofl^ this 

 water of vegetation. Now what have we left .= 

 To go back to our process of analysis, let us char 

 the dried root. Wo drive off more water and vol- 

 atile parts. This water did not exist as such in 

 the plant. It existed there as hydrogen and oxy- 

 gen gas. Now this word gas is a chemical term, 

 and it means any substance in vapor, which cannot 

 be condensed into a liquid or solid at common 

 temperatures. Different gases may unite, and so 

 become solids or liquids. Steam is not gas, for it 

 is the vapor of water, and immediately returns to 

 the state of water, below 212 degrees. Perfect 

 steam is invisible ; so are most gases. The air 

 we breathe is composed of two gases, o.tygen and 

 nitrogen. We do not see them — we cannot by 



JAJr. 34, 184 



it to decay ; we obtain exactly the same products | the coal or carbon of mould without its salts 

 as we did by our analysis, that is, carbon and salts. 'this worn-out land salts, and you may by 



we leave ' ' 



But because there is not heat enoutrh 



alone bring it back not only to 



tl 

 its first vi 



th 



an it was before man 



by decay a portion of the hydrogen and n.xygen j freshness, but vou may even by salts alone n 



still united to the coal. A slow mouldering fire ' 



leaves products more like those of decay. Decay 



is a slow mouldering fire; hence the products of 



the decay of plants are very aptly termed mouU. 



It is the product of a mouldering fire— that is, an 



imperceptible union of the oxygen of the air with 



the carbon of the plant, — a union so slow that it 



gives out neither heat nor light. And yet it is in 



Its results the same as if fire had actually been 



seen and felt. Mould contains, then, a part of the 



carbon, o.vygen, and hydrogen, or, if you like the 



terms better, mould of soil consists of the water 



and coal and salts of the plants. Mould is truly 



manure. If the mould of soil, as it has thus been 



defined, were separated from the earthy portions 



ofsoil, it would deprive that SOU of the power of hold yet a great deal of insoluble coal ofm'o 



growing crops. Here then, we come to abroad 



it fairer and richer 

 cultivated it. 



Too much stress has been all along laid u 

 the kind of soil. Go now to " Flob," in W 

 Cambridge : no better farms or farmers, look 

 world through. Ask any of these practical 

 whether the sandy and gravelly soil of Old C 

 bridge Common, or even of Seekonk Plain, can 

 made to bear as rich crops as their land ? T 

 will tell you, yea. If your land will hold man 

 muck it well, and it will bo as good.* Nov 

 holding of manure belongs to the subject of sc 

 and throwing that out of consideration, it is fo 

 that even lands which do not hold 



manure, wl 

 have been worn out and exhausted by cropp 



come to a 



distinction between soil and manure. The soil is 

 the eartli on which plants grow. The mould is 

 the manure of that soil. The soil is the earthy; 

 the mould, that is, the carbon and salts together, 

 with the elements of water, are the vegetable part 

 of arable land. But though the earthy part, the 

 soil, as it is usually called, acts as a support, on 

 which plants grow, it does not play a merely me- 

 chanical part. It has a distinct, decided, and im- 

 portant action upon the manure. The action is 

 chiefly chemical ; and the fact that soils and ma- 

 nures do mutually affect the growing plant, is 

 proved by the circumstance, that the first plants 

 which grew, derived their salts from the earth. 



But this chemical action of soil does not belong 

 to the present discussion. We can understand 

 what manures are, without deciding how they act. 

 We can theorize and guess about the how of their 

 action when we have learned what they are. That 

 is chiefly what the farmer wants to know. He 

 wants to know what manure is, and what is likely 

 to act as a manure. To these points we shall con- 

 fine our present remarks. Pointing out the great 

 principles applicable to all manures, the nature of 

 soils, and the manner in which they affect manures, 

 must be left for another essay. The vegetable or 

 manure part ofsoil alone is to be now considered. 

 Consider now, reader, the groat results to which 

 our analysis has led us; that a slow, mouldering 

 fire gives us the same products as arc formed by 

 decay; that this is only a slow, mouldering fire, 

 and that mould, its product, is the natural manure 

 of plants. It follows, that whatever substance 

 produces mould, that is, water, carbon, and salts, 

 may be used instead of this natural manure. 



cooling or compression make air lake other shape | Among the salts found in mould, some are volatile 

 it, on ;r,.,:„;Ki» „;. tu;. ;_ .l- i . ^ ._ i . _ _ -i ,■ ... _ . 



than invisible air. This is the general properly of 

 gas as distinguished from vapor or steam. Oxygen 

 and hydrogen in plants exist in just the propor- 

 tions to form water, but we do not know that they 

 are united in these proportions. We have com- 

 pelled them to unite by heating the substance or 

 root. The carbon is by this same process con- 

 sumed, and you know, has thus formed carbonic 

 acid. Besides this, a portion of the carbon unites 

 with some of the hydrogen of the plant. This 

 forms light, inflammable air. Now you may col- 

 lect this light, inflammable air in any stagnant wa- 

 ter where plants are decaying. Decay gives ex- 

 actly the sa.me products as are formed in making 

 charcoal. Decay is only slow combustion or burn- 

 ing ; no matter whether we char the plant or leave 



and are easily dissolved by water. Others are 

 fixed, that is, not evaporating easily, or not at all, 

 and are quite insoluble in water. Now the first 

 or volatile and soluble, first act when used in ma- 

 nure. They act quick and are quickly done. The 

 fixed and insoluble act slower ; they last longer. 

 The volatile act in the early stages of growth ; the 

 fixed in the later periods. The great difference 

 in the action of manures, depends almost entirely 

 upon the salts which they contain. These are the 

 most important and essential. It is not so much 

 the vegetable mould of manure that you want, as 

 the salts which it contains. This is a well settled 

 principle. Land which has undergone the skin- 

 ning process — old, worn out and run out land, still 

 contains a very large portion of vegetable matter ; 



They want salts, and something which will m 

 this inert, dead vegetable matter of the soil, act 

 The mould is active in proportion as it is mor< 

 less dissolved by water. Mould consists of 

 parts ; one is dissolved, though only in a sli 

 degree, by water; the other is not dissolved 

 water. Some substances, however, do rer 

 mould very easily dissolved by water. Henct 

 you reflect a moment on these facts, it will be s 

 that mould itself, being valuable in propnrtioi 

 the ease with which water dissolves it, that wI 

 ever substance so enables mould to dissolve, r 

 be added to it, and thus increase its value. N 

 the things which do this are the alkalies, sc 

 potash, and ammonia. 



These principles being well settled, we may i 

 ler on the consideration of each different manu 

 They will bo valuable in proportion to the quani 

 and kind of salts each contains, added to the pov 

 they may have of producing by their decay si 

 stances which make their mould soluble. N 

 this last property, that is, the property of produci 

 a substance which makes mould soluble, depei 

 wholly upon the nitrogen of the manure. This 

 trogen, in the process of decay, becomes volal 

 alkali, or ammonia. The word ammonia will c 

 cur so often in the present discussion, that 

 should endeavor to fix some definite idea to 

 You need not, reader, be acquainted with all 

 chemical properties. I suppose every man w 

 will be likely to read these remarks, has smell 

 ammonia. It has been already said, that it giv 

 the peculiar pungent smell to the common sme 

 ing bottle. This is volatile ammonia. It is ; 

 ways formed when animal or vegetable bodies c 

 cay. 



It has been already said, and is now repeated 

 order that it may never be forgotten, that amni 

 nia is formed by the union of hydrogen and nitt 

 gen. Hydrogen and nitrogen, two airs, nitrog 

 forming four-fifths of the air we breathe — let th 

 be borne in mind, and without going into the chei 

 istry of ammonia further, or the inode of calcul 

 ting how much ammonia a pound of nitrogen w 

 make, it may be laid down, and must be remembe 

 ed, too, that every pound of nitrogen may be call< 

 two and a halfpounds of sal volatile, or smellir 

 salts of the smelling-bottle. Two and a half lb 

 of volatile ammonia formed from one pound of r 



"The reader will bear in mind that Dr. Dana ua 

 " muck" as a general term for manure — not moanit 

 simply the muck of the meadow. — Ed. 



