gal. of fuel oil will give heat equivalent to 1,000 cu. ft. of
coal gas.

The pressure of oil and air used varies with the system installed.
The low-pressure system maintains a pressure of about 8 oz. on the
oil and draws in free air for combustion. Others use a pressure
of several pounds, while gas burners use an average of perhaps
1-1/2 lb. of air to give best results.

The weights and volumes of solid fuels are: Anthracite coal, 55 to
65 lb. per cubic foot or 34 to 41 cubic feet per ton; bituminous
coal, 50 to 55 lb. per cubic foot or 41 to 45 cubic feet per ton;
coke, 28 lb. per cubic foot or 80 cubic feet per ton--the ton being
calculated as 2,240 lb. in each case.

A novel carburizing furnace that is being used by a number of people,
is built after the plan of a fireless cooker. The walls of the
furnace are extra heavy, and the ports and flues are so arranged
that when the load in the furnace and the furnace is thoroughly
heated, the burners are shut off and all openings are tightly sealed.
The carburization then goes on for several hours before the furnace
is cooled below the effective carburizing range, securing an ideal
diffusion of carbon between the case and the core of the steel
being carburized. This is particularly adaptable where simple steel
is used.

PROTECTIVE SCREENS FOR FURNACES

Workmen needlessly exposed to the flames, heat and glare from furnaces
where high temperatures are maintained suffer in health as well as
in bodily discomfort. This shows several types of shields designed
for the maximum protection of the furnace worker.

Bad conditions are not necessary; in almost every case means of relief
can be found by one earnestly seeking them. The larger forge shops
have adopted flame shields for the majority of their furnaces. Years
ago the industrial furnaces (particularly of the oil-burning variety)
were without shields, but the later models are all shield-equipped.
These shields are adapted to all of the more modern, heat-treating
furnaces, as well as to those furnaces in use for working forges;
and attention should be paid to their use on the former type since
the heat-treating furnaces are constantly becoming more numerous
as manufacturers find need of them in the many phases of munitions
making or similar work.

The heat that the worker about these furnaces must face may be
divided in general into two classes: there is first that heat due
to the flame and hot gases that the blast in