Page:Cassells' Carpentry and Joinery.djvu/113

half their depth into the pail of mixture, care being taken not to allow any to get on the surface, and lightly tapped into place; when a bay is completed a piece of quartering about 5 ft. long, with one side planed straight, should be struck on the face of the blocks to bring them to a uniform level.

In laying the herringbone design (Fig. 391), begin with the margin, laying this as far as the mastic runs; then taking two blocks, place them in the left-hand angle, and make a mark on the margin where the edge of the second block reaches. This will be the point for fixing the small triangular piece, marked No. 1; next fix the block marked 2, and then Nos. 3, 4, 5, 6, 7, in due order. This arrangement makes the insertion of the tongues or pins easy. Having reached No. 7, either move to the right, or let the second man take up the running with block No. 8, whose position is found by measuring from No. 6 with two blocks as before; then let him follow on with Nos. 9 to 14 consecutively, when the first man will lay Nos. 15 and 16, and the second Nos. 17 and 18, and so on.

The shaded portion in Fig. 391 represents the recess between a chimney-breast and the wall. If a beginning were made against a straight wall all the three pairs of contiguous blocks should be laid first right along that side—that is, all of those having mitred ends, as these provide the starting points of the pattern, then follow on alternately left and right as described.

A beginning should always be made at the wall opposite the door, working towards the latter so that no traffic may pass over fresh-laid work; and after all the blocks are down, sawdust should be freely strewn over their surface to absorb any mastic that may have dropped thereon, and scaffold boards laid on spare blocks from the doorway, should it be necessary to pass that way. At least twenty-four hours should elapse before beginning the cleaning off, to allow the mastic time to set hard, and in cleaning off plenty of tallow should be used. It will be found an advantage to the workmen to have a pail of whiting handy, whilst they are laying the blocks, into which they can occasionally dip their hands, as the tar burns severely the unprotected skin.

As before mentioned, the blocks should be all cut to size before beginning, and this necessitates the setting out of one "repeat" of the design full size upon a large board or a clean floor. The actual blocks should be