For brickwork, the _Builder_ gives the following remedy:--¾ lb. of mottled soap to 1 gal. of water. This composition to be laid over the brickwork steadily and carefully with a large flat brush, so as not to form a froth or lather on the surface. The wash to remain 24 hours to become dry. Mix ½ lb. of alum with 4 gal. of water; leave it to stand for 24 hours, and then apply it in the same manner over the coating of soap. Let this be done in dry weather. Another authority says, coat with venetian red and coal tar, used hot. This makes a rich brown colour. It can be thinned with boiled oil. A Devonshire man recommends “slap-dashing,” as is often done in Devon. The walls are, outside, first coated with hair-plaster by the mason, and then he takes clean gravel, such as is found at the mouth of many Devonshire rivers, and throws--or, as it is called locally, “scats” it--with a wooden trowel, with considerable force, so as to bed itself into the soft plaster. You can limewash or colour to your liking, and your walls will not get damp through. Perhaps no application is cheaper or more efficacious than the following. Soft paraffin wax is dissolved in benzoline spirit in the proportion of about one part of the former to four or five parts of the latter by weight. Into a tin or metallic keg, place 1 gal. of benzoline spirit, then mix 1½ lb. or 2 lb. wax, and when well hot pour into the spirit. Apply the solution to the walls whilst warm with a whitewash brush. To prevent the solution from chilling, it is best to place the tin in a pail of warm water, but on no account should the spirit be brought into the house, or near to a light, or a serious accident might occur. The waterproofed part will be scarcely distinguishable from the rest of the wall; but if water is thrown against it, it will run off like it does off a duck’s back. Whilst it is being applied the smell is very disagreeable, but it all goes off in a few hours. On a north wall it will retain its effect for many years, but when exposed much to the sun, it may want renewing occasionally. Hard paraffin wax is not so good for the purpose, as the solution requires to be kept much hotter. Curing a Damp Cellar.--A correspondent inquired of the editor of the _American Architect_ what remedy he would suggest for curing a damp cellar. The difficulty to be overcome, presents the questioner, in a new house is the wet cellar. Conditions present, concrete not strong enough to resist the hydraulic pressure through a clay soil. No footings under wall (which are of brick.) No cement on outside of wall. The water evidently, however, forces its way through the concrete bottom. (_a_) Will reconcreting (using Portland cement) resist the pressure of water and keep it out? (_b_) If not, will a layer of pure bitumen damp-course between the old and new concrete do the work?