610 SELECTIONS FROM ADDRESSES. 



to the new growth. These latter ingredients are discharged at 

 the roots as excrementitious matter, and these processes are con- 

 tinually going on. 



It may be thus understood. If a cabbage be suddenly pulled 

 from the soil and the dirt washed from the surface of its stem, 

 and it then be plunged into a jar of chemically pure water, the 

 following phenomena will take place. After a short time the 

 water will become milky, and in a few hours small flocculent 

 particles will be seen to descend to the bottom until, if the 

 cabbage be of ordinary size, the jar six inches in diameter, a 

 deposit of one inch depth of semi-starch-like consistency will 

 occur. If this be poured around the roots of another cabbage 

 it will kill it, if poured around a beet, carrot, or parsnip, it will 

 materially increase its growth. Thus it will be seen that the 

 excrementitious matter of one plant is pabulum to another, and 

 hence the necessity for rotation of crops, a plant not being able 

 to grow in the presence of an excess of material unfriendly to, 

 or not required by, its organism. 



Some crops do not throw off much excrementitious matter. 

 Thus the onion beds of Wethersfield have in some instances 

 been grown upon the same soil for a hundred successive years. 

 The farmer, therefore, in choosing the crops which should fol- 

 low each other, can readily decide upon them by reference to 

 their analysis, and avoid a repetition which would embrace 

 similar ultimate constituents. 



A much more important branch for the consideration of the 

 farmer is the sub-succession of crops. This may be said to 

 apply more particularly to the gardener, but is fully worthy 

 the farmer's best consideration. Several crops may be raised 

 from the same soil in the same year, and despite this fact many 

 are contented with a crop of early cabbages, leaving the ground 

 in July, permitting it to be useless for the plants of the season ; 

 or of early potatoes dug in July or August^ in either of which 

 cases turnips might have been raised, Caulo Rapas, late cab- 

 bage, and a variety of other crops. Gardeners, by judicious 

 management, have some twenty or thirty different four-course 

 rotations for the single season. Thus let us suppose a crop of 

 early potatoes, planted in early spring in hills at the usual dis- 

 tance apart ; thirty days before these potatoes are ripe a cab- 

 bage plant may be set out between each four hills, making the 



