7). The webbing is attached to the underside of a wooden frame, which can be of varying depth. The spacing between the webbing strands, however, must be adjusted so that each spring can be centered upon the lap formed by the crossing of the longitudinal and lateral webbing strips. A frame with inside dimensions of 18 in. by 24 in., for example, can house only six springs 4 to 5 in. in diameter. Therefore, in order to center the springs on the crosswise laps of webbing which is 4 in. wide, the two longitudinal strands must be spaced 1Y2 in. apart with their outer edges 3r4 in. from the inside edges of the long sides of the wooden seat frame. The three lateral strands can be spaced at equal distance of 3 in. The folded ends of all strips are fastened with as' many tacks as the webbing and framework will accommodate. The springs are placed in position with the bentdown ends uppermost, in order to protect the stuffing. They are then sewed to the webbing laps with stitching twine by means of a 6in. straight, doublepointed upholsterer's needle. The stitching is commenced from the bottom, goes through the webbing, over the bottom of the spring and back to complete four double loops, the last pair nearest the next spring as in Figure 6.7. The stitches should be small in order to prevent undue wear, and the twine knotted, preferably after the last one of each pair of stitches, and certainly after the last of each of the four pairs, to prevent the loosening of all six springs if one stitch should break. When the base consists of wooden cleats, large staples can be driven in to fasten the spring bottoms. Tying the springs. After the stability afforded by the base, the most important factor in this type of upholstery is that of the proper tying of the springs. The hempen twine not only holds the springs in an upright position, but also provides a solid support for the burlap covering, which in turn supports the stuffing. For this reason each spring is tied with a minimum of eight knots in four directions. Expert tiers employ their own time and laborsaving methods and reduce the number of separate pieces of twine to a minimum. The amateur upholsterer, however, will do well to estimate the amount of twine required by means of a rough tule of thumb, such as multiplying the total dimensions of the frame by 1%, t erwards cutting the individual pieces for lateral, longitudinal, and diagonal iymg, with a minimum allowance of at least 18 in. at each end for "return ties." In tying builtin springs it is customary to commence operations from the rear. 360 FURNITURE MAKING AND CABINET WORK Disregarding individual professional whimsies, the easiest method for the beginner who is faced with tying six springs in a removable base 3 to 4 in. deep is to work from the top of all but the outermost springs. The twine is laid across the tops of the three longitudinal springs, for example, with the ends thrust through the centers of the two external springs.