New York Consolidated Laws, General Business Law - GBS § 321. Standard of illuminating power

The maximum illuminating power required and minimum illuminating power permitted of gas so furnished or supplied in any such city shall be as follows:  If a coal gas, sixteen candles;  if a mixed coal and water gas, eighteen candles;  and if a carburetted water gas, twenty candles.  A candle shall mean a sperm candle, six to a pound, burning at the rate of one hundred and twenty grains of spermaceti per hour.  The test for illuminating power shall be made with gas obtained from a service pipe or main located at a distance of not less than one mile nor more than one and one-half miles from any distributing holder, using, for coal gas and mixed coal and water gas containing more than fifty per centum of coal gas an F Argand burner, and for mixed coal and water gas containing fifty per centum and less of coal gas and for carburetted water gas a number seven slit union Bray burner, on a basis of consumption of five cubic feet of gas per hour.