coke in one of these gas producers, we give the following typical
analysis on the authority of Dr. William Wallace, F.R.S.E., gas
examiner, and one of the public analysts for the city of Glasgow:

Per cent.
Hydrogen 8.7
Carbonic oxide 28.1
Carbonic acid 3.5
Oxygen 0.4
Nitrogen 59.3
-----
100.0

By again referring to Fig. 2, it will be observed that an opening is
provided for the passage of the gaseous matter as it is formed into the
mass of brickwork, the upper half of which is occupied by the retorts of
the setting and the lower by the regenerators.

Before following the gas we may first direct attention to the
arrangements for dealing with it, and with the air that has to be
admitted for the combustion of so much of it as is of a combustible
nature. It will be seen by reference to Fig. 1 that the oven proper is
occupied by eight [Inline Illustration] shaped retorts. These are 9 ft.
long (set back to back) by 18 in. by 13 in., and they are placed on
arches which are 8 ft. 6 in. wide. Underneath the level of the retort
oven there are two regenerators or regenerator chambers, which differ
very materially in form from the regenerators formerly applied by Dr.
Siemens to gas retort ovens, and which are still employed for high
temperature furnaces like those used for steel and glass melting. In
the case of these latter the regenerators are on the alternating