1125. To increase the number, and improve the qualities of plants, it is necessary to facilitate their mode of nutrition by removing all obstacles to the progress of the plant. These obstacles may either exist under or above the surface; and hence the origin of draining, clearing from surface incumbrances, and the various operations, as digging, ploughing, &c., employed for pulverising the soil. Nature suggests this in accidental ruptures of the surface, broken banks, the alluvial depositions from overflowing rivers, and the earth thrown up by underground animals. Many of the vegetables within the influence of such accidents are destroyed, but such as remain are ameliorated in quality; and the reason is, their food is increased, because, their roots being enabled to take a more extensive range, more is brought within their reach.