TWELFTH ANNUAL YEAR BOOK— PART X 515 



causes the oil to dry, and no additional drier is necessary. In fact, red 

 lead should not be mixed until just before it is used. A paint made of 70 

 per cent of red lead and 30 per cent of linseed oil will weigh about 19.8 

 pounds to the gallon. A gallon of paint, therefore, will contain 13.86 

 pounds of red lead, which costs about 8 cents a pound, making the cost 

 of the pigment in a gallon of this paint approximately $1.11. The 30 per 

 cent of linseed oil will weigh 5.94 pounds, and a gallon of linseed oil 7.75 

 pounds, costing about 90 cents at the present time, or 11.5 cents a pound. 

 The oil in the paint will cost then about 68 cents, and a gallon of red-lead 

 paint would cost $1.79, as compared with 83 cents for a gallon of oxid of 

 iron paint. These two paints will cover about the same area of clean 

 iron, and while somewhat better service might be expected from the 

 red-lead paint, it is more than twice as expensive as the iron-oxid 

 products. 



WHITEWASH. 



Whitewash is the cheapest of all paints, and for certain purposes it is 

 the best. Lime, which is the basis of whitewash, makes a very sanitary 

 coating, and is probably to be preferred for cellars and the interior of 

 stables and other outbuildings. The following directions for making 

 whitewash are taken from "White Paints and Painting Materials," by W. 

 G. Scott: 



Ordinary whitewash. This is made by slaking about 10 pounds of 

 quicklime with 2 gallons of water. 



The lime is placed in a pail and the water poured over it, after which 

 the pail is covered with an old piece of carpet or cloth and allowed to 

 stand for about an hour. With an insufficient amount of water, the lime 

 is "scorched" and not all converted into hydrate; on the other hand, too 

 much water retards the slaking by lowering the heat. 



"Scorched" lime is generally lumpy and transparent, hence the use of 

 the proper amount of water for slaking and an after addition of water 

 to bring it to a brush consistency. 



Factory whitewash. (Interiors) '.For walls, ceilings, posts, etc. 



(1) Sixty-two pounds (1 bushel) quicklime, slake with 15 gallons of 

 water. Keep barrel covered until steam ceases to rise. Stir occasionally 

 to prevent scorching. 



(2) Two and one-half pounds rye flour, beat up in % gallon of cold 

 water, then add 2 gallons of boiling water. 



(3) Two and one-half pounds common rock salt, dissolve in 2V2 gallons 

 of hot water. 



Mix (2) and (3), then pour into (1) and stir until all is well mixed. 



This is the whitewash used in the large implement factories and rec- 

 ommended by the insurance companies. The above formula gives a 

 product of perfect brush consistency. 



Weatherproof whitewash. (Exteriors) : For buildings, fences, etc. 



(1) Sixty-two pounds (1 bushel) quicklime, slake with 12 gallons of 

 hot water. 



(2) Two pounds common table salt, 1 pound sulphate of zinc, dissolved 

 in 2 gallons of boiling water. 



