Every age has been the dupe of empiricism; and the greater its darkness, the more impudent appear to have been the pretensions of knavery. We may even now, perhaps, swallow a few matters, the arcana of the needy or the daring, in the various compositions of powders, draughts and pills, which are not quite agreeable to our palates or our stomachs; but our forefathers had more to encounter, as they had more faith to support them, when they were subjected, for the cure of their maladies, to such medicines as _album græcum_, or the white bony excrement of dogs, bleached on the bank, for their heart-burns and acidities; the powder produced from burnt mice, as a dentifrice; millepedes, or wood-lice, for nephritic and other complaints; and the ashes of earth-worms, administered in nervous and epileptic cases. Our apple-trees here are greatly injured, and some annually destroyed by the agency of what seems to be a very feeble insect. We call it, from habit, or from some unassigned cause, the “American blight” (aphis lanata);[67] this noxious creature being known in some orchards by the more significant name of “white blight.” In the spring of the year a slight hoariness is observed upon the branches of certain species of our orchard fruit. As the season advances this hoariness increases, it becomes cottony, and toward the middle or the end of summer the under sides of some of the branches are invested with a thick, downy substance, so long as at times to be sensibly agitated by the air. Upon examining this substance we find, that it conceals a multitude of small wingless creatures, which are busily employed in preying upon the limb of the tree beneath. This they are well enabled to do, by means of a beak terminating in a fine bristle: this, being insinuated through the bark, and the sappy part of the wood, enables the creature to extract, as with a syringe, the sweet, vital liquor that circulates in the plant. This terminating bristle is not observed in every individual: in those that possess it, it is of different lengths, and is usually, when not in use, so closely concealed under the breast of the animal, as to be invisible. In the younger insects it is often manifested by protruding like a fine termination to the anus; but as their bodies become lengthened the bristle is not in this way observable. The alburnum, or sap wood, being thus wounded, rises up in excrescences and nodes all over the branch, and deforms it; the limb, deprived of its nutriment, grows sickly; the leaves turn yellow, and the part perishes. Branch after branch is thus assailed until they all become leafless, and the tree dies.