All that has been said with respect to illumination on vellum applies, with equal force, to illumination on paper. There has to be borne in mind, however, the essential difference that exists between the relative durability of the two substances. Elaboration is decidedly a great element of beauty in illumination: and neatly-wrought elaboration cannot be executed without care, patience, and a considerable sacrifice of time: why, therefore, bestow that care, patience, and time upon a less permanent material, when one only a trifle more costly, but infinitely more lasting, is as easily procured? Work on paper, therefore, only as you would write exercises or do sums upon a slate; learn and practise upon paper, but reserve all more serious efforts for vellum only. No effect can be got upon the former material, which cannot, with a little more dexterity, be attained upon the latter. As none of the other substances mentioned as those on which illumination may be executed are available for making up into books, before proceeding to a consideration of the special conditions under which the art may be applied to them, I beg to offer the following recommendations with respect to design, as suitable for book-illustration generally.[98] Firstly:--Take care that your text be perfectly legible; for, however cramped and confused the contents of many of those volumes we most admire may now appear, it is to be remembered that they were all written in the handwriting most easily read by the students of the periods in which they were written. The old scribes never committed the solecism of which we are too often guilty, of bestowing infinite pains on writing that which, when written, not one in a hundred could, or can, decipher. Secondly:--Fix the scale of your writing and ornament with reference to the size of your page, and adhere to it throughout the volume. This rule, which was rigidly observed in all the best periods of the art, is incessantly disregarded in the present day; and to such an extent, that not only does scale frequently differ, as we turn page after page, but the same page will frequently exhibit scroll-work, derived from some great choral folio, interwreathed with leafage borrowed from some pocket Missal or Book of Hours.