FROM MEMPHIS, TENN.
Grains per
Gallon.
Silica.8292
Oxides of iron and aluminium.4789
Carbonate of lime1.8337
Carbonate of magnesia.9956
Carbonate of soda1.9792
Total solids6.1166
FROM PEKIN, ILL.
Grains per
Gallon.
Silica1.0628
Oxides of iron and aluminiumTrace
Carbonate of lime10.0915
Carbonate of magnesia5.8224
Chloride of sodaTrace
Sulphate of soda1.2456
Total solids18.6471
FROM TIFFIN, OHIO.
Grains per
Gallon.
Silica.5256
Oxides of iron and aluminium.2336
Carbonate of lime12.6144
Carbonate of magnesia10.2652
Carbonate of soda2.4137
Sulphate of soda6.8296
Chloride of sodium1.0484
Total solids33.9395

CORROSION AND INCRUSTATION OF STEAM BOILERS.

No more perplexing question presents itself to the engineer and steam user than the one to be inferred from the above heading. Enormous losses of money, danger to life and property and the loss of position and the reputation of the engineer are involved in it. How to avoid these actual evils is of the first importance in steam economy. The subject at first sight seems to the average student a difficult one to master, but like all other matters pertaining to mechanics, investigation that is backed with reason, will show that much that appears obscure is really very plain indeed; this is because nature, even down to the sediment remaining in a boiler after the conversion of water into steam, operates in its formation with infinite exactness and along well known lines.

Question.—What is corrosion?

Answer.— Corrosion is simply rusting or the wasting away of the surfaces of metals, for particulars of which see page [126.]

Question.—What is incrustation?