One precaution must be strictly observed if the grainer wishes to produce clean work, and that is, to be sure that his ground is perfectly firm and dry before he begins, so that this ground is not likely to be torn or rubbed off with the combing or veining. I like a ground to be dry but not too hard or oily, as when dry, but soft, it will produce more feeling work, particularly if the grainer is using the most useful of all his tools, the thumb-nail. A grainer's thumb, like a miller's, has a great deal to do with the making of sham oak; therefore you may easily distinguish a professional oak-grainer by the length, strength, and tender care which he lavishes on his thumb-nail. It ought for this purpose to be kept long, and carefully rounded and smoothed. The tools required for this work are a box of assorted combs, two or three pieces of soft cork cut with notches, plenty of soft cotton or linen rags, and that properly trimmed thumb-nail. He will also require for oak-over-graining the same brushes which he uses in the soft woods; camel-hair softeners, grainers and over-grainers, with wipers-out and sash-tools, &c. The next thing he will make up is his scumble. This is composed of burnt umber, yellow ochre, drier, boiled oil, a little beat-up putty or whiting, and a small quantity of water. By mixing all this up together you produce something like a stained megilp, and may thin it with oil and water as you go on. A little of this goes a long way, as it has to be spread over very sparingly and equally. Get a good specimen of real oak, well coursed with _champs_ or 'veins,' and set it up before you where the light will fall best upon it; then, after rubbing down your grounded panel with fine sandpaper, and dusting it carefully, you will put a little 'scumble' upon it with your sash-tool, and spread that over equally and thinly with a larger brush until the panel is covered. Take your largest toothed comb, and trail it steadily down the panel from top to bottom, wiping the comb carefully after every passage. It is better to trail the large comb in straight lines, and afterwards use the smaller or finer toothed combs with a shake to produce wavy lines. When you have passed the combs over the panel in this way, first the coarse comb straight, next the medium size with a wave, and lastly, in portions, the finest size comb, your panel is ready for the artistic portion of the work. Combing does not take long to learn if the worker is cleanly in his habits, but to make a natural and pleasing variety in 'champing' or veining takes a great deal of practice; indeed, unless the worker has artistic gifts, he will never be able to master this part of the work perfectly.