(11,088 - 6,134) / 4,954 = 87.5 per cent.
--_eighty-seven and one-half per cent_., or a saving in dollars and
cents of four thousand nine hundred and fifty-four dollars ($4,954).
In this city, Philadelphia, no allowance for the consumption of water is
made in the case of first class engines, such engines being charged the
same rate per annum per horse-power as an inferior engine, while,
as shown by the above example, a saving in water of _thirty-one and
four-tenths per cent_. has been attained by the employment of a
first-class engine. The builders of such engines will always give a
guarantee of their consumption of water, so that the purchaser can be
able in advance to estimate this as accurately as he can the amount of
fuel he will use.
* * * * *