252 



THE GENESEE FARMER. 



Nov. 



to it by the hand of the cultivator. What is this 

 important change, which so uniformly follows the 

 skilful use of rural implements, and which would not 

 ensue, if no plowing or tillage was performed ? The 

 proper answer to this question, is the first thing we 

 have to study. 



Before plowing, the ground is comparatively com- 

 pact and impervious to air. After it has been well 

 plowed and harrowed, it is exceedingly porous and 

 mellow, to the depth which the implements have 

 penetrated. The atmosphere over every field and 

 . here, always contains several gaseous bodies, 

 called oxygen, or vital air, nitrogen, or azote, car- 

 bonic acid, and occasional traces of ammonia, and 

 volatile compounds of phosphorus, sulphur and chlo- 

 rine. These gaseous substances, with the addition 

 of a few earthy substances, like pure flint, iron, lime, 

 potash, soda, and magnesia, make up the whole 

 weight of all vegetables and animals. Technically 

 speaking, a soil is formed by the intimate union of 

 pure mold, derived from partialiy decayed leaves, 

 trees, grass, weeds, the bodies of insects, and all 

 other vegetable or animal matters, with pure clay, 

 sand, and other incombustible earths. The propor- 

 tions of mold, sand, 'day, &lc, vary indefinitely. 

 Experience has demonstrated the interesting fact, 

 that a soil which is annually plowed and hoed, and 

 from which all the plants that grow are removed, 

 loses its mold, or organic matter quite rapidly. If 

 the ground be well cultivated, and no vegetable what- 

 ever be allowed to grow therein, the consumption or 

 decomposition of the remains of former vegetation, 

 will still go on quite as fast as it would, provided the 

 surface were shaded by a crop. Indeed, my own 

 opinion is, founded on what I have seen in Georgia 

 and South Carolina, that organic matter in a naked 

 plowed and hoed field, will be consumed, literally 

 burnt up, much faster than will mold, or similar or- 

 ganized matter, shaded by a forest of trees, or a forest 

 ick corn or cotton. How tillage hastens the 

 consumption of mold, and the solution of the before 

 laratively insoluble salts, which appear as ashes 



, i we burn wood or cultivated plants, deserves 

 particular notice. 



A cubic inch of hard wood, like a cubic inch of 

 hard earth, will imbibe little or no gas or air. By a 

 curious law of nature, a cubic inch of charcoal will 

 absorb and condense within its innumerable cavities, 

 ninety cubic inches of ammonia. It will also con- 

 dense other gases and vapors. In garden culture, 

 and first rate field tillage, the soil is thoroughly mel- 

 lowed, and rendered remarkably porous. 



Now let us see what nature does, man having 

 done his part. The atmospheric air, which is twenty- 

 one per cent of oxygen, penetrates as far as the plow 

 did, and is largely condensed in the pores of the soil. 

 During the day, if the air is comparatively dry and 

 the sun sliines, a pretty rapid evaporation will ensue. 

 Instead of drying a well cultivated surface, as it 

 would a compact one, moisture freely ascends from 

 the subsoil, by capillary attraction, to fill the void 

 above. In this ascent of water, is brought up what- 

 ever soluble gases, mold, and salts of potash, lime, 

 etc., rain or snow water had taken out of the sur- 

 face soil in its previous descent. If the ground be 

 covered with vegetables, a large share of this ascend- 

 ing water will enter 1 heir roots, ascend to their le 

 and there escape as a vapor into the atmosphere; 

 leaving behind those salts and gases reqaired to or- 

 ganize and bring up the plant. If no vegetation 



exists and covers the ground, the water evaporates 

 as it reaches the surface, leaving all involatile salts 

 behind, and discharging all gasses into the air. At 

 night, and when the atmosphere is quite damp and 

 the soil dry the latter condenses dew or vapors, as 

 the case may be, preparatory to feeding crops. 



A due degree of solar heat, light, moisture, and 

 of condensed oxygen, around minute particles of the 

 debris of plants in tilled ground, greatly promotes 

 the chemical combination of this oxygen with the 

 carbon in the mold, or the remains of plants. 



When mold is thus consumed, this oxygen and 

 carbon form the gas called carbonic acid; the pres- 

 ence of which in water enables it to dissolve com- 

 mon limestone. This mineral (carbonate of lime) 

 is quite insoluble in distilled water. All rain water 

 contains a little carbonic acid as it falls, which pre- 

 pares it to dissolve the inorganic food of plants. To 

 raise large crops, it is needful for water to have a 

 little more of this gas than the atmosphere can fur- 

 nish. Manure and decaying vegetables will yield 

 this in mellow soils. 



As not far from one-half of the dry weight of all 

 plants, and some forty percent of all animals is car- 

 bon, it may be a favor to readers whose knowledge 

 of chemistry is very limited, to say a few words 

 about this element. If wood, straw, coffee, wheat, 

 sugar, oil, starch, or lean meat, be slowly burnt, 

 with the air nearly all excluded, on the principle of 

 a coalpit, coal will be formed. This coal is carbon. 

 The simple element is the same in anthracite and 

 bituminous coal, as in coal produced from a crust of 

 bread. In burning, this carbon unites chemically 

 with vital air, called oxygen, in the proportion of 

 six parts by weight of carbon, to sixteen of oxvgen: 

 which, together make twenty-two parts of an invisi- 

 ble, heavy gas, called carbonic acid. 



If we examine the air thrown out of the lungs of 

 a man or other animal for this gas, it will be found 

 to contain one hundred times more carbonic acid, 

 than it did when inhaled into the lungs. As animals 

 breathe night and day during their whole lives, and 

 are ever expelling carbon from their organs of res- 

 piration, it is obvious they must supply carbon to 

 their circulating blood, in their food, at short inter- 

 vals. On comparing the dry weight of all the matter 

 excreted from the system by the bowels and kidneys. 

 with that taken into the stomach, the weight of the 

 latter exceeds that of the former by more than half. 



From some experiments which I have made, I 

 have reason to believe that the excretions of birds 

 when dried, do not exceed twenty per cent of the 

 dry matter eaten by them. If we examine the bub- 

 bles of gas that rise so freely on the surface of fer- 

 menting beer, in the large tubs of breweries and 

 distilleries, it will be found to be carbonic acid; and 

 i; i.-; often used to convert pearlash into saleratus; or 

 the carbonates of potash and soda into the bicarbo- 

 nates of those alkalies. 



There is then, a natural tendency, or rather a nat- 

 ural law, by the force of which oxygen gas combines 

 with carbon in the combustion of carbonaceous bodies, 

 in all respiration, in all fermentation, and in the rot- 

 ting of all organized substances. The reader will 

 get a clearer idea of the part which carbon plays in 

 the economy of vegetable and animal life, by a short 

 explanation of the other constituents united with it, 

 in organizing the seeds and other parts of plants. 

 The other elements of what is called "organic mat- 

 ter," are nitrogen or azote, hydrogen and oxygen; 



