The ‘caillou,’ alas, like the poet who struck this spark out of it, is now obsolete; but _amadou_ is still in vogue, being employed for many household purposes; in addition to which, a medical practitioner of Covent Garden has of late been in the habit of using extensive sheets of it to cover over and protect the backs of those bedridden invalids whose cruel sufferings make such large demands upon our sympathy,—for the alleviation of which so little is to be done!—as it is more elastic than chamois leather, it is less liable to crumple up when lain upon, and on this account has been preferred to it by several of our metropolitan surgeons of eminence; some employ it also as a gentle compress over varicose veins, where it supports the distended vessels without pressing too tightly upon the limb. Gleditsch relates, that the poorer inhabitants of Franconia stitch it together, and make dresses of it; and also that the Laplanders burn it in the neighbourhood of their dwellings, to secure their reindeer from the attacks of gadflies, which are repelled by the smoke; thus “good at need,” it really deserves the epithet of ‘puissant,’ given to it by Delille.[53] The _Polyporus squamosus_ makes a razor-strop far superior to any of those at present patented, and sold, with high-sounding epithets, far beyond their deserts. To prepare the _Polyporus_ for this purpose, it must be cut from the ash-tree in autumn, when its juices have been dried and its substance has become consolidated; it is then to be flattened out for twenty-four hours in a press, after which it should be carefully rubbed with pumice, sliced longitudinally, and every slip that is free from the erosions of insects be then glued upon a wooden stretcher. Cesalpinus knew all this! and the barbers in his time knew it too;[54] and it is not a little remarkable that so useful an invention should, in an age of puffing, advertisement, and improvement, like our own, have been entirely lost sight of. Imperato employed and recommends it as an excellent detergent, with which to brush and comb out the scurf from the hair.