Parchment being an animal substance (usually made from the skin of sheep), if kept in a damp place, soon begins to decay and become offensive, mites readily attack it, dirt and dust accumulate rapidly on its external woolly surface--all these make a search among hoards of old deeds anything but a pleasant or a cleanly occupation. The usual storehouse for such collections was some unused garret or stable-loft, where rats and mice ran riot and birds flew in and out as they liked. Forgotten, perhaps, for several generations, the old papers lay untouched till death or removal brought changes, and the deeds were either placed in safer keeping, or else--alas! the most usual course--were consigned to the flames as useless rubbish. The quality of parchment varies much. That upon which early deeds--those about the thirteenth century--are written, is in small pieces, woolly in texture and of a dark brown shade. In the sixteenth century the sheets are larger, smoother, and yellow, becoming whiter in colour and more even as its preparation was better understood and practised. Vellum was a finer sort of parchment prepared from the skins of very young or still-born animals. Of it the old manuscript books were made, adorned with illuminations and miniature paintings, which required a fine, smooth surface, and vellum was free from the flaws which frequently occur in the skins of mature animals. With the history of paper-making we have nothing to do. Paper was known as early as the thirteenth century, but for law work in England it was seldom, if ever, employed before the fourteenth century. The earliest known examples are described as being made of silk manufactured abroad. On the Continent it was used for illuminated work in the place of vellum--at least, so Prou states, but does not tell us of any notable examples.