Maps that have to be prepared for hanging on walls are always provided with a roller at top and bottom; these may be stained and varnished or covered with colored paper. The mounted maps are glued and tacked to the half-round rollers. Where all round rollers are used they should be ordered in halves. The edges of the map are glued between and the two halves then nailed together. Rings are screwed into the top roller for hanging, and also a few tapes to tie up the rolled map if required.

Plates and maps, as also placards, are also varnished. Varnishing is nowadays always done with spirit varnish, which is convenient for working. All papers cannot be simply varnished and done with-the nature of the paper must be taken into consideration. All sized and chromo papers may be varnished without preparation. Many notepapers, especially unsized and copperplate papers, must first be sized, which prevents the resinous parts from penetrating and thus avoids grease spots.

The best of all means is glue or gelatine; the former turns the paper somewhat yellow. A thin solution is made, which is laid on warm with a large sponge in long quick strokes. Where color or ink is to be dealt with, no parts should be touched twice or the colors will be effaced. . A second coating, however, may be given after the first has dried. The spirit varnish -to be used-called map or photo varnishes still too thick as sold. It is thinned with 90 % spirit of wine to the required consistency until it runs easily from the brush.

Wide varnish brushes with lead fastenings are used. Two coats of thin varnish are better than one coat of thick.

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