60 



ANALYTICAL CLASS-BOOK OF BOTANY. 



vegetable body, with a view of arriving at more just and 

 certain laws in agricultural operations. He classes cul- 

 tivated vegetables under four heads, namely : 



(1) ALKALI PLANTS, represented by Potatoes and 

 Beets ; 



(2) LIME PLANTS, represented by Clover and Peas ; 

 "(3) SILEX PLANTS, represented by the Grasses ; 



(4) PHOSPHOROUS PLANTS, represented by Wheat and 



Rye. 



325. But while the organic bases have been abun- 

 dantly supplied from the organic remains of which 

 manures are generally composed, and which constitute a 

 large portion of the rich, black earth known as humus, 

 or pure vegetable mould, little or no attention has been 

 given, to the necessary supply of proper material for 

 supporting the inorganic bases. Let cultivators who 

 now act too exclusively on the forcing system, set aside 

 the old idea, that it is the richness of the soil alone, or 

 chiefly, which will insure good crops. If this is so, why 

 do not bogs, which are exceedingly rich in humus, pro- 

 duce in abundance such plants as affect a moist soil ? 

 So far is this from being true, that bogs are very poor 

 in plants ; and those they do produce are of the 

 coarsest kinds. If the water which sometimes covers 

 them did not wash away the inorganic elements, leaving 

 little else beside humus, they would produce abundantly 

 many of the plants which now are so rarely found among 

 them. This should teach us that we cannot, by any pro- 

 cess of manuring, convert one element into another. We 

 cannot change lime into soda, potash into sand, or humus 

 into either. We cannot make Potatoes, which want 

 potash, or Grasses that call for pure silex, submit to 

 accept of the richest mould as a substitute. 



326. Let us, then, by a careful analysis, ascertain 

 the inorganic constituents of plants, and then provide 

 that every species shall have its proper mineral food pre- 

 sent in the soil, and ready to be appropriated. The 

 stalks of Grasses, and especially those of the Cereal 

 Grains, could not be formed with sufficient strength to 

 support the ripened head, without a proper quantity of 

 silex, however rich in other elements the soil may be ; 

 nor could albumen and gluten, which give to Maize, 

 Wheat, and all the cereal grains, their chief value, be 

 elaborated without the presence of phosphoric acid ; and 



His classification Alkali plants Lime plants Silex plants Phosphorous 

 plants. Instances. What bases supplied from most manures ? What other 

 bases Important name of rich black mould of what composed ? Why do not 

 bogs produce abundantly all plants that like wet? What exchanges cannot\>o 

 made ? What should be done ? What required by grass stalks what to form 

 albumen what sugar, starch and cellulose is the alkaline salt taken up by 

 them ? What should all plants have ? What analysis, and what ascertained by 



although there is not a particle of alkaline salt in sugar 

 starch and cellulose, neither of them could be produced 

 without the presence of such salts. Thus all plants 

 should have a full supply of the mineral nutriment which 

 their constitution demands. By burning and analyzing 

 the ashes of a healthy plant, it can be ascertained pre- 

 cisely what elements are taken up, and therefore what 

 kinds, and in what proportion, should be supplied. This 

 explains the necessity of a rotation of crops; for the 

 whole secret consists in regulating the condition of the 

 soil to the demand of the crop, or the reverse, in adapt- 

 ting the crop to the soil. 



327. The importance of the Inorganic elements may 

 be inferred from the fact, that more than one third of the 

 human body, by weight, consists of earthy matter. This 

 must be supplied chiefly through the vegetable portion of 

 its food ; for since all animals have bones and teeth to 

 form for themselves, it follows that the mineral matter 

 contained in the vegetable substances on which they feed, 

 would not be deposited so liberally in the flesh, and, 

 therefore, that they can be obtained more abundantly 

 direct from the vegetable tissues, by which aloue they are 

 directly transferred to organism. The inhabitants of 

 frigid climes are uniformly small, short, and altogether 

 deficient in the development of bone; and this may 

 doubtless be attributed to their poor supply of vegetable 

 food, and consequently of those substances that furnish 

 the most abundant and best material for the osseous 

 structure. 



CHAPTEK XXIII. 



INFLORESCENCE. 



328. HAVING now completed a review of the Vege- 

 tative Organs, we come to quite another and a very dif- 

 ferent class. Yet, however unlike these may appear in 

 external form, texture and coloring, you will find that 

 they all have their origin in the Leaf. This organ is the 

 type of all those above it, from which they always depart, 

 and to which they sometimes return. 



329. Still ascending from the Leaf upward, the next 

 thing that arrests the attention is the varied manner in 

 which flowers are assembled on their stalks. This is 

 termed INFLORESCENCE. 



it? Of what does it explain the necessity? In what does the whole secret 

 consist? Importance of Inorganic elements from what fact, inferred? By 

 what food is the osseous structure chiefly nourished why not from animal 

 food ? Inhabitants of the frigid zone why small frames? 



General subject What other class of organs ? In what do they originate ? 

 In ascending from the leaf, what first arrests attention what termed ? 



