It is very good practice to copy some pictures when there is something in them that we wish to learn, yet cannot see how to do from nature. For instance, you may learn how to glaze and scumble better from a picture than from nature, because the glazings and scumblings of nature are too subtle for us to follow always so directly. You will also learn how painters of repute managed a certain phase or effect of colour, subject, or composition. Rubens will liberate you from many a stiffness, and give you in his own buoyant style the liberty and joyful colouring you may be deficient in. Vandyke will teach you refinement and dignity; Tintoretto, richness; Michael Angelo, the boldness and firmness of handling and drawing, the severity and squareness needful for majestic grandeur. Amongst our own men, I quote John Pettie for a strength and richness that have never been surpassed, bring what master of long-ago you like to the competition; Orchardson for pure and delicate texture; Sir Frederick Leighton for finish; Millais for realism in its best sense; Alma-Tadema for imitation and learning; and a host of other men, both good and true, who must improve the mind, the eye, and the hand. Millais has said that an artist ought to begin as he did, pre-Raphaelite, if only to learn the quality of Job. Nature eventually must make him, as she has made that great realistic master, broad and strong, if it is to be, though a whole world of critics were to chorus against it. Speaking of critics, I think we may divide them into two classes--the psychological and the destroying, or vermin, species. The first class look at a painting or a book as we ought to look at everything--with the bee spirit, to suck out all the honey there is in it. They are of equal use to the public and to the worker; for, leaving one to see the errors that all man's work has, they lay the good before the other, benefiting equally themselves in the instruction they have gained. As for the other class, do they help the work done, or that has to be done? do they add to the pleasure of the spectator, or instruct the worker by their pertness or sneers? Do moths add to the value of clothes? does mildew improve walls? does rust assist the brightness of polished steel? or do white ants strengthen the rafters they bed in? True, these are all works of nature and creatures of God. The decay must be as useful as the life, or it would not be. But what made critics of this class? From what? For what? Discreet copying, as I have said, is very good; but there is only one other practice as pernicious as indiscriminate and constant copying, and that I will speak of presently. What is glazing and scumbling? Scumbling is going over distance with white or grey, rubbing it hard and dry, so as to obscure the parts that stand too prominently out; it softens harshnesses, sends back portions, and does its part in aiding the general harmony of the distance and middle distance.