Hand printing
In the printing of wallpaper, each color or tint is applied by means of a separate block or roller – blocks being used for hand printing and rollers for machine printing. In hand printing, a rectangular block is cut so that its surface presents, in relief, the elements of all parts of the design that are in one color or tint. The paper, which is in a continuous roll, is at the end of a long table, by which the printer stands, the paper being at his right. Behind him and also to his right are placed the tray of color and the color pad on which he places his block, holding it by means of one or two handles on the back. He carefully transfers the block to the surface of the paper where it is printed by pressure effected by means of the long wooden elbow that the printer pulls straight, so as to brace the block against the paper with a thrust of the wooden elbow against the ceiling. The block, in printing, marks on the edge of the paper a guide so that the following block may be placed so as to impress the second color in its proper place. As the block is printed, the paper is moved along the repeat and carried over cross-bars, or stick, in long loops or folds so as to dry thoroughly before it is rolled to pass through the process again for the printing of the second color. Each color is thus applied successively until the entire surface of the paper is impressed with the design, and for each color applied the paper passes under the printer's hands and is impressed with a separate block. Although the finest papers are printed in this way, most of the hand-printed papers are imported from Europe. A few American manufacturers produce hand prints that that compare very favorably with the imported article, but the price is so high, and the demand for high-priced paper so limited, that most wallpaper designers in the country confine themselves to the preparation of designs for machinery production.

Machine Printing
In machine printing, each section or color of tint is printed from a separate roller; while the paper moves around a large drum, Fig. 1, it comes successively in contact with each color roller before the previous color has dried. This causes machine printed papers to blend their colors and prevents the clean, sharp distinction of outline that is characteristic of the hand-printed papers. Some wallpapers are printed in two colors only – one the background and the other a diaper or surface design – these are printed from a single roller as the background is printed on a separate machine. In Fig. 2 are shown several wallpaper rollers, each of which presents a complete design; whereas in Fig. 3 are shown a number of rollers where each presents but a fraction of the design, the entire twelve rollers being necessary to complete the pattern in its several colors.

The Method of Making the Rollers
A very important detail in the process of machine printed paper is the preparation of the rollers so that they will exactly imprint all the details of the pattern in the successive colors and present a harmonious whole.
This work is executed by skilled workmen and is often a slow an laborious process. The rollers are made from maple logs turned exactly to the required size, which is regulated by the length of the repeat. Where a design calls for a number of colors, each roller must be turned to exactly the same diameter, within the minutest fraction of an inch, before the design can be executed on its surface. After being turned to the required size, the rollers are painted white, and, when dry, are given a traced impression of the entire pattern. Upon each roller is then marked its part of the pattern; and it is then given to the block cutter. The smallest details on these surfaces are made of solid pieces of brass, formed to the proper shape by being drawn through steel dies. These are then driven into the surface of the roller at the proper places. Circular dots, etc. are made of brass wire cut into pieces ½ inch or less in length, and with the sharp end driven, with a hammer, into the roller at the required point. Larger surfaces are outlined with thin strips of brass that are skillfully filed and bent to the required forms, and then sharpened on the lower edge so as to be driven into the wood after the outline has been cut in with a knife or a chisel. This outline of brass is driven firmly and solidly into the wood, somewhat less than ¼ inch of its length being left above the surface. When this work is complete, the spaces within these brass outlines are filled with heavy felt that has been soaked in hot glue. When the felt dries, it forms a hard and perfectly solid printing surface within the brass outline.
The rollers are then placed on a lathe and trued up, or ground, to the finished diameter, which makes their circumference exactly equal to the repeat on the paper. When all the rollers have passed through these processes and are finished to the exact circumference, they are ready for the printing machine.

In Fig. 1 is shown a machine on which an eight-color ceiling paper is being printed. The paper is fed in at the bottom and on the opposite side of the machine, from whence it passes around a large drum, as shown, and comes in contact with the various color rollers, after which it passes off at the top of the machine with the paper completely printed. The strip is then carried, in long loops, over a coil of stream pipes by means of which the colors are thoroughly dried before the paper reaches the opposite end of the long building, where it is rolled up by machinery and so cut that each roll contains exactly the same amount.

Differences between Hand-Printed and Machine-Printed Papers
Having considered the two methods of manufacture, let us observe the differences in appearance of hand-made paper and machine-made paper. Comparing [hand-printed] with [machine-printed] and observe that, while the details of the former are perfectly sharp and distinct, and probably determine accurately the appearance of the designers originality, the tones are softened in the [machine-printed] so that one blends into another much as in ordinary water-color painting; these facts should be taken into consideration.

The Colors
The colors in which the printing is done are comprised of a mixture of the required pigment ground in water and thickened with glue and dextrine.
They must be of such a consistency that they do not blur or blend into one another to any great extent, and at the same time must be thin enough to flow readily from the surface of the felt belts and properly cover the rollers.
The colors are supplied to each roller by means of felt belts that are so adjusted that they pass through troughs containing the color and distribute it accurately to the printing rollers so that each receives just the proper amount. This is determined by experiment, as the belts are readily adjusted to change the amount of color being fed, and should it be found that as the paper passes through the machine too much or too little is being distributed, the belts can be adjusted in position so as to vary the amount.
It is evident, too, that as the amount of color can be varied as it is distributed on the rollers, and that the amount of blurring and softness of effect can be regulated by the quantity of size or glue that is mixed with it, quite a variety of effects in design can be obtained where the designer understands the possibilities of these color mixtures in manufacturing details. In many machine-printed papers that possess a number of colors, this blurring is very conspicuous and is frequently a means of rendering the paper more interesting than it would be where each detail was in sharp outline . . . When gold is used on a design, it should be arranged so as to fall entirely clear of any color, and whether executed as an outline to some form or in masses, it should be distinct in its own particular shape so that there may be no difficulty in getting the block that is to determine its printing on the wallpaper. Gold is not printed directly from a roller, as are the colors, but as the paper passes through the printing machine, the last roller in which it comes in contact impresses the design on the general surface in varnish which is much slower drying than the water colors with which the rest of the paper is printed. After all the water color has dried, this sizing of varnish is still sticky, and gold or bronze powder sifted over the paper will adhere to this sizing while it may be brushed off the rest of the paper.