Fire and water proof cement for roofs of houses. Slack stone lime with boiling water in a covered barrel; when slacked pass six quarts through a fine sieve; to this add one quart of rock salt, and a gallon of water, boil the mixture and skim it clean; to every 5 gallons of this add 1 lb. of alum, and 1/2 lb. copperas, and add by degrees, potash 3/4 lb., and fine sand or wood ashes sifted 4 quarts; colour to suit your taste and apply. It will be as durable as stone. 410. BUG POISON Take of spirits of wine 1/2 pint, turpentine 1/2 pint, crude sal-ammoniac 1 oz; mix all together and let it saturate for seven days, and it is ready for use. 411. DISINFECTING AGENT Take of green vitriol 3 lbs., hot water one pailful; dissolve the vitriol in the water; place this wherever there is any offensive odours, as that of a corpse, cesspool, privies, &c., and in a short time all smell will be removed. Try it. 412. BOOTH PATENT Booth's patent grease for railway axles, waggons, machinery, &c. Take of water 1 gallon, clean tallow 3 lbs.; palm oil 6 lbs., and common soda 1/2 lbs.; or tallow 8 lbs., and palm oil 10 lbs. The mixture is to be heated to about 210 degrees, and well stirred till it cools down to about 70 degrees, when it is ready for use. 413. GUM-ARABIC STARCH Take 2 oz. of white gum-arabic powdered finely; put it into a pitcher and pour on it a pint of boiling water; then cover it and let stand all night; in the morning pour it carefully from the dregs into a clean bottle; cork and keep it for use. A tablespoonful of this gum water stirred into a pint of starch that has been made in the usual manner will give to launs either black, white, or printed, the appearance of new, to which nothing else can restore them after washing. It is a good article for collars and shirt bosoms; also, when much diluted, for thin white muslin and bobbinet. 414. ROMAN OR MASTIC CEMENT Take of pulverised sand stone sifted fine, 20 lbs., litharge 2 lbs., mix both well with linseed oil to the consistency of paste; brush both broken parts over; press them snugly together, and let them dry, this forms an excellent cement. 415. PORTABLE BALLS For taking stains out of cloths, &c.--Dry fullers' earth so as to crumble it into powder, and moisten it well with lemon juice; add a quantity of pure pulverised pearl-ash, and work the whole up into a thick paste with a little water; roll it into small balls; let them completely dry in the sun, and they will be fit for use. The manner of using them is to moisten, with water, the spots on the cloth, rubbing the ball over, and leaving it to dry in the sun. On washing the spots in the water they will immediately disappear. 416. CLOTH, RAIN PROOF, &c. To render cloth wind and rain proof. Boil together 2 lbs. of turpentine, 1 lb. of litharge in powder, and 2 or 3 pints of linseed oil. The article is then to be brushed over with this varnish, and dried in the sun. 417. CHOICE CEMENT