It is almost impossible to erase pencil lines from vellum. The black lead, uniting with the animal matter of the skin, can never be properly got out--India rubber or bread only rubbing it into a greasy smudge. It is, therefore, better to prepare a complete outline of the design upon paper first, which can afterwards be transferred to the strained sheet. For this purpose _tracing paper_ is required, possessing this advantage, that corrections upon the sketch can be made in tracing, and, in placing it upon the vellum, if the sheet has been previously squared off for the work, its proper position can be readily seen and determined. The tracing paper should be about one inch larger each way, to allow of its being fastened to the mask over the exposed surface of the page. A piece of _transfer paper_ of a convenient size is then placed under the tracing. When the tracing is fixed in its proper position by a touch of gum or paste at the upper corners, slip the transfer paper, with the chalked side downwards, between the vellum and the tracing, and tack down the bottom corners of the tracing in the same way, to prevent shifting. Seated at a firm table or desk of a convenient height, with the strained paper or drawing board slightly on an incline, the amateur may consider all ready for work. All the lines of the tracing are first to be gone over with the tracing point, or a very hard pencil cut sharp will answer the purpose. A corner may be raised occasionally to see that the tracing is not being done too firmly or so faintly as to be almost invisible. A piece of stout card should be kept under the hand while tracing, to avoid marking the clean page with the prepared transfer paper underneath, by undue pressure of the fingers. For larger work, not requiring such nicety of detail, the sketch may be transferred direct--especially if the paper is thin--without the use of tracing paper, by merely chalking the back of the drawing, and going over the lines with the tracing point; but the other method is best, and the transfer paper may be used over and over again. When the subject is carefully traced on the prepared page, and the tracing and transfer paper removed, it will be best to begin with the text. The experienced illuminator will generally, after arranging his designs and spacing out his text, with the initial letters in their proper places, transfer all to his vellum, and do the writing before he begins coloring, covering up all the page except the portion he is working upon. When the lettering is complete, it will in its turn be covered, to prevent its being soiled while the border is being painted.