Ink ought to be reduced to an impalpable smoothness, either in a mill or on a stone with a muller. This is essential, as the process gives it the next quality,—that of completely yet very thinly covering the surface of the type or the lines of the engraving, and insuring an even and perfect appearance to the impression on the paper. Another important requisite is, that the ink shall not only cover the surface of the lines on the paper printed, but that it shall also quit the face of the type or engraving and leave it quite clean when the paper is impressed on it, and attach itself to the paper, so as to give a perfect impression of the subject represented, without the colour of the paper appearing through the ink; and that this peculiarity of quitting the type or engraving and becoming attached to the paper shall continue the same through any number of impressions, without any accumulation of ink on the surface printed from. After having obtained these results, and when the printing is as perfect as it can be made by workmanship, something more is requisite,—viz.: that the ink shall not smear on being slightly rubbed, and that it shall retain its colour and appearance without spreading at the edges or tinging the paper. The rollers should be in good condition; otherwise the pressman may exert his skill in vain, with a great loss of time and waste of paper. The quality of the paper is of great consequence in fine printing; but it is frequently overlooked by the printer’s employers, who are apt to pay more attention to a showy appearance and a low price than to quality. The best paper for printing on is that which is made of fine linen rags and moderately sized, without the use of acids in bleaching, and without being adulterated with cotton rags: this paper takes water kindly, is easily got into good condition, receives a good impression, is durable, preserves its colour, and does not act upon the ink. The use of cotton rags, the introduction of gypsum into the manufacture of fine and other papers, the application of acids and bleaching powders to improve the colour and produce apparently good paper from an inferior staple,—these form the grand hinderances to the American printer in his efforts to equal or excel foreign productions. Hence it is that works printed in this country are less valued than those from the English press, which are printed on paper of fine fabric, made mostly of linen rags, and sufficiently strong to bear a fine ink. A pressman should, as a matter of course, be well acquainted with the entire routine of presswork; in addition to which, to form his judgment, he should examine the most splendid productions of the press, and study them as patterns of workmanship.