FRAME POLISHES: See Polishes.
FRAMING, PASSE-PARTOUT: See Passe-Partout.
FRECKLE LOTIONS: See Cosmetics.
FREEZING MIXTURES: See also Refrigeration and Refrigerants.
FREEZING PREVENTIVES
Liquid For Cooling Automobile Engines.
A practical manufacturing chemist of wide experience gives this:
A saturated solution of common salt is one of the best things to use. It does not affect the metal of the engine, as many other salts would, and is easily renewed. It will remain fluid down to 0° F., or a little below.
Equal parts of glycerine and water is also good, and has the advantage that it will not crystallize in the chambers, or evaporate readily. It is the most convenient solution to use on this account, and may repay the increased cost over brine, in the comfort of its use. It needs only the occasional addition of a little water to make it last all winter and leave the machinery clean when it is drawn off. With brine an incrustation of salt as the water evaporates is bound to occur which reduces the efficiency of the solution until it is removed. Water frequently must be added to keep the original volume, and to hold the salt in solution. A solution of calcium chloride is less troublesome so far as crystallizing is concerned, but is said to have a tendency to corrode the metals.