OLUE AND GUM hl\ 



To REMOVE RUST. 



14. Heavily rusted iron may be cleaned by immersing it in a bath 

 (not too acid) of chlorid of tin, for twelve to twenty-four hours. After 

 removing, rinse in water and then in ammonia. 



15. Rusted steel may be brushed with a paste of ^ ounce cyanide 

 potassium (poisonous), | ounce castile soap, 1 ounce of whiting, and 

 water. Then wash in 2 ounces water containing \ ounce cyanide. 



Amount of paint required for a given surface. 



It is impossible to give a rule that will apply in all cases, as the 

 amount varies with the kind and thickness of the paint, the kind of wood 

 or other material to which it is applied, the age of the surface, etc. The 

 following is an approximate rule : Divide the number of square feet of 

 surface by 200. The result will be the number of gallons of liquid 

 paint required to give two coats ; or divide by 18, and the result will 

 be the number of pounds of pure ground white lead required to give 

 three coats. 



Glues 

 Liquid glue. 



1. Dissolve 2 pounds of best pale glue in a quart of water in a cov- 

 ered vessel, placed in a hot-water bath; when cold, add to it 7 ounces 

 of commercial nitric acid. When cold put in bottles. 



2. Finest pale orange shellac, broken small, 4 ounces ; methylated 

 spirit, 3 ounces ; put in a warm place in a closely corked bottle until 

 dissolved. Should have the consistency of molasses. Or, borax, 1 

 ounce ; water, f pint ; shellac as before ; boil in a closely covered 

 kettle until dissolved ; then evaporate until nearly as thick as 

 molasses. 



Flower gum. 



3. Very fine white shellac mixed with methylated spirit in a stone 

 jar ; shake well for half an hour and place by a fire, and shake it 

 frequently the first day. Keep in a cool place. Leave the camel's- 

 hair brush in the gum. Never fill the brush too full and gum the petals 

 close to the tube. 



