1877-78).

The use of carbonate of soda is also cheaper than all other above
mentioned substances.

One milligramme equivalent sulphate of lime, in 1 liter, = 68 grammes
sulphate of lime in 1 cubic meter, requiring for decomposition:

120 gr. (86-88 per cent.) chloride of barium of commerce--at $5.00 =
0.6c.

Or, 50 gr. magnesia preparation--at $10.00 = 0.5c.

Or, 55 gr. (96-98 per cent.) carbonate of soda--at $7.50 = 0.41c.

The proportions of cost by using chloride of barium, magnesia
preparation, carbonate of soda, will be 6 : 5 : 4.


ARRANGEMENT FOR PURIFYING BOILER-WATER WITH LIME AND CARBONATE OF SODA.

We need for carrying out these manipulations, according to the size
of the establishment, one or more reservoirs for precipitating the
impurities of the water, and one pure water reservoir, to take up the
purified water; from the latter reservoir the boilers are fed. The most
practical idea would be to arrange the precipitating reservoir in such
manner that the purified water can flow directly into the feeding
reservoir.

The water in the precipitating reservoir is heated either by adding