138 



THE CELLS AND CIROULATION OP PLANTS. 



The leading idea is not to permit any element of 

 fertility to escape, either by solar evaporation or 

 leaching and washing; but compel growing plants to 

 absorb and assimilate the maximum of their appro- 

 priate food. As an e.xperiment, the plan ia worthy of 

 close investigation; for, having the irrigating pipes 

 made of well burnt clay, they will last under ground 

 for ages; — and manure in some form has always to be 

 applied to tilled land from which annual crops are 

 taken. Whether there is any better way than to 

 spread it by hand and plow it in, is the question now 

 before the pnblic. By dissolving manure in water, it 

 can be conveyed to the land that needs it, and evenly 

 distributed either over the surface of the ground, or 

 a foot or two under it by steam-power. Some years 

 may elapse before either plan is brought so near per- 

 fection as to force itself into general use; but the 

 wise investment of capital in farming operations is a 

 point too little studied by the present generation. 

 Commerce, merchandise, railroads, and manufactures 

 absorb much of the wealth drawn primarily from the 

 soil. When farmers shall learn to keep iheir capital 

 in their own business, as well as produce it, and fully 

 understand the principles of their noble calling, they 

 will have both the means and the confidence required 

 to make tillage and husbandry vastly more produc- 

 tive and less toilsom6 than they now are. Thousands 

 now invest their surplus earnings in bank stocks, or 

 otlier securities foreign to agriculture, because they 

 lack confidence in the progress of their own profes- 

 sion. They dare not study closely even its scientific 

 elements, lest it should tempt them into some unpro- 

 fitable experiment. People walking in the dark are 

 always more timid than those walking in the full light 

 of the sun. It is the darkness that surrounds the 

 growth of agricultural plants which retards the much 

 needed improvements in feeding them. Science will 

 dispel this darkness so soon as public opinion tole- 

 rates its general cultivation. Not only the science 

 of feeding plants, but the art of tillage — never plow- 

 ing less than is profitable nor more than is profitable — 

 demands investigation Some use the hoe too much, 

 particularly in the planting States, and some too lit- 

 tle. Every process ought to be carefully considered, 

 with a view to economise labor and increase its pro- 

 ducts. How many worthless implements are now in 

 general use in all parts of the United States, causing 

 a serious loss of muscular toil and of crops? Good 

 tools would add from ten to twenty per cent to the 

 agricultural income of the nation — but good tools 

 cost money. Look where we may, we discover the 

 want of capital to augment the fruitfulness of Amer- 



ican soil, wherever it is cultivated. If we were lesi 

 extravagant in our personal habits and notions, anc 

 saved money, instead of speedily consuming it, anc 

 grubbing along with old plows, harrows, wagons, anc 

 other dilapidated " fixings," we might supply ourselvei 

 with the best tools, machines, and implements in th( 

 civilized world. It is bad economy not to have ever 

 laborer work to the best advantage. This principli 

 leads to the invention of all labor-saving machines 



THE CELLS AND CIRCULATION OF PLABTS. 



Vegetable physiology has long taught us to be 

 lieve that wood in trees is formed corporeally frou 

 above downwards; and the theory is suggested, an^ 

 apparently proved, by the enlargement of the bod 

 of a growing tree, or of one of its limbs when a stou 

 ligature is tied round it, above the point where th 

 ligature is placed. This preteraatural enlargemer 

 has been ascribed to the accumulation of the pabi 

 lum of woody fibre in the obstructed vessels and eel. 

 lying in the inner bark of the tree, through whic 

 passes the descending sap. Recent experiment 

 however, go to show that the vascular circulation (■■ 

 plants is restricted to the conveyance of organizabJ 

 matter, and that it never distributes organized sul 

 stances. This distinction is important to the rigl 

 understanding of the relations that subsist betwec 

 a graft or new bud which is made to grow on a diffe 

 ent stock. Pomologists have hitherto supposed thw 

 inasmuch as the wood of trees grows downwarcl 

 the extending tissues of the graft would soon pa* 

 down over the wood of the stock and under tU 

 bark, perhaps quite to the extremities of the too* 

 in the ground. This opinion is now abandoned t 

 the best physiologists who have studied the growl 

 and functions of different cells, alike in buds, fruil 

 leaves, stems and roots of plants. Starch, sug8< 

 oil, gum, wood, and coloring matter are all formed 

 the cells where they are found ; and they are nevn 

 transferred from one organ to another. Near tH 

 beginning of September, 1853, Dr. Allen Macleaj 

 of Colchester, England, an ingenious e.xperimeutalii 

 and physiologist, grafted a young plant of the Sill 

 sian white beet upon a root of red beet, and one i 

 the latter upon a root of the former. At the tinl 

 of the experiment the plants were each about n 

 thick as a straw. A complete union wa.s olfcclec 

 but there was a slight contraction at the line of juni 

 tion. The white beet grafted on the red retained i- 

 natural color down to the hue of junction, as did t! 

 red beet up to that line. Had there been any mil 

 gling of colors by vascular circulation, or otherwis' 



