In wooden buildings the walls should be made even, so that when the plastering is put on, the wall will present no "ins and outs." This may be effected by trimming all the timbers down to an equal width before lathing.

Stone and brick walls should be furred with strips; for brick they are one by two inches, nailed to the bond timbers laid in the walls, once in nine or ten courses, as they are built up, and for stone two by four inches, nailed to plugs or wedges, built up with or driven into the walls. These furring strips are placed sixteen inches apart from center to center, and the lathing nailed to them.

In the best houses it is customary to cross-fur on ceiling joists, as when done, the plastering is less liable to crack.

Laths should be made of spruce, pine, or other soft woods, and thoroughly seasoned and dried. The mortar should be made of first quality of quicklime and good sharp sand, mixed with plenty of long hair. Ceilings should first be gauged with a mortar of plaster-of-Paris and lime, followed by a coat of browning, or common mortar, and finished with a white, hard putty coat made of plaster and quicklime. In the better class of houses, three coats are given to the ceilings, and two to the walls; this prevents the laths from showing through the plaster. All angles should be smoothed down, and corners made straight and true. Stucco cornice and plaster ornaments for ceilings are giving way to paper, which is now prepared in beautiful designs expressly for ceilings.