Before taking any calorimeter reading, steam should be allowed to flow through the instrument freely until it is thoroughly heated.

The latter difficulty is undoubtedly due, in certain instances, to the form of flange in which the strain of the connecting bolts tended to distort the metal.

The specific heat of air at constant pressure varies with its temperature.

If less than this amount of air is supplied, the carbon burns to monoxide instead of dioxide and its full heat value is not developed.

The ratio based on combustible will be greater than the ratio based on fuel if there is unconsumed carbon in the ash.

Gas-house coke is generally softer and more porous than oven coke, ignites more readily, and requires less draft for its combustion.

The heat evolved in burning of a definite weight of standard naphthaline may also be used as a means of calibrating the calorimeter as a whole.

The cost of up-keep in a chain grate, properly constructed and operated, is low in comparison with the same cost for other stokers.

Tan bark is burned in isolated cases and in general the remarks on burning wet wood fuel apply to its combustion.

Care should be taken where this fuel is used to install a suitable apparatus for straining it before it is fed to the burner.

This is best accomplished by an attachment which permits the blowing out of the burners by steam.

The gases available for this class of work are almost invariably very dirty.

The makers furnish a non-drying oil for the liquid, usually a 300 degrees test refined petroleum.

The duration in such cases may be reduced, and the “flying” method of starting and stopping employed.

The other factors entering into such determination are the size of the plant and the character of the feed water.

Special care should be taken to prevent air, steam or water leaks into the boiler or onto the pressure parts to obviate danger of corrosion.

After the walls have become thoroughly heated, coal may be fired and the boiler placed in service.

All surfaces should be painted before the covering is applied. Canvas is ordinarily placed over the covering, held in place by wrought-iron or brass bands.

Napier deduced an approximate formula for the outflow of steam into the atmosphere which checks closely with the figures just given.

The actual transfer rates in superheaters are affected by so many conditions that it has not so far been possible to evolve any formula of practical value.