If it is necessary that the binding should be repaired, nothing should be destroyed. If, for example, a portion of the back has been lost, what remains should be kept, and not an entirely new back put on. In repairing calf bindings, morocco should be used, as near the colour of the original as possible, and the grain should be pressed out. The old end-papers should, of course, be retained, and nothing of any kind destroyed which affords a link in the history of the book. No attempt should be made to ornament the repaired portion so as to resemble the rest of the binding; it serves no useful purpose, and takes away considerably from the good appearance and value of what is left, for a binding which has been ‘doctored’ must always be looked upon with some mistrust. An old calf book should never be varnished; it does not really help to preserve it, and it gives it an unsightly appearance, besides tending to fill up the more delicate details in the ornamentation. Some writers recommend that old bindings should be rubbed with vaseline or other similar preparations. Nothing is better than good furniture cream or paste. A few drops should be lightly rubbed on the binding with a piece of flannel; it should be left for a few minutes, until nearly dry, and then rubbed with a soft dry cloth. Not only does this soften the leather and prevent it getting friable, but it puts an excellent surface and polish upon it, quite unlike that produced by varnish. When a binding is in good condition and the surface not rubbed through, it is best to leave it alone; if any dusting or rubbing has to be done, it should be done with a silk handkerchief. CHAPTER XIII. THE COLLECTING AND DESCRIBING OF EARLY PRINTED BOOKS. It is exactly one hundred years since Panzer, “the one true naturalist among general bibliographers,” published the first volume of his _Annales Typographici_, and in this period two distinct methods of bibliography have grownup. The more popular, generally associated with the name of Dibdin, treats specimens of early printing merely as curiosities, valuable only according to their rarity or intrinsic worth, or for some individual peculiarity found in them. The other method, of which Panzer was the first practical exponent, was called by Henry Bradshaw the Natural History method. Each press must be looked upon as a _genus_, and each book as a _species_, and the more or less close connection of the different members of the family must be traced by the characters which they present to our observation. Bradshaw’s own work is the best example of this method, and a beginner can follow no better model than the papers which he wrote on early printing.