It is not without reason that the term "sacred" is applied above to the written words or characters. The Chinese, recognizing the extraordinary results which have been brought about, silently and invisibly, by the operation of written symbols, have gradually come to invest these symbols with a spirituality arousing a feeling somewhat akin to worship. A piece of paper on which a single word has once been written or printed, becomes something other than paper with a black mark on it. It may not be lightly tossed about, still less trampled underfoot; it should be reverently destroyed by fire, here again used as a medium of transmission to the great Beyond; and thus its spiritual essence will return to those from whom it originally came. In the streets of a Chinese city, and occasionally along a frequented highroad, may be seen small ornamental structures into which odd bits of paper may be thrown and burnt, thus preventing a desecration so painful to the Chinese mind; and it has often been urged against foreigners that because they are so careless as to what becomes of their written and printed paper, the matter contained in foreign documents and books must obviously be of no great value. It is even considered criminal to use printed matter for stiffening the covers or strengthening the folded leaves of books; still more so, to employ it in the manufacture of soles for boots and shoes, though in such cases as these the weakness of human nature usually carries the day. Still, from the point of view of the Taoist faith, the risk is too serious to be overlooked. In the sixth of the ten Courts of Purgatory, through one or more of which sinners must pass after death in order to expiate their crimes on earth, provision is made for those who "scrape the gilding from the outside of images, take holy names in vain, show no respect for written paper, throw down dirt and rubbish near pagodas and temples, have in their possession blasphemous or obscene books and do not destroy them, obliterate or tear books which teach man to be good," etc., etc.