rick, and, besides, filled with refractory bricks piled up as shown in
the figure. The partitions, C and C', are likewise of refractory brick,
and are rendered as air-proof as possible. Apertures, D and D', are
formed alternately at the base of one partition and the top of the
adjacent one, in order to oblige the gases that traverse the series of
chambers to descend in one of them and to rise in the following,
whatever be the number of chambers in use.

The two flues, E and E', lead from the bottom of the two nearest
regenerator on each side to the bottom of the generator A, and serve to
bring the current of air or steam into contact with the fuel. Valves, F
and F', placed in these flues, permit of regulating the current in the
two directions. Pipes, M and M', provided with valves, G and G', put the
upper part of the generator in communication with the contiguous
chambers, T and T'. Other pipes, N and N', with valves, H and H', permit
of the introduction of a current of air from the outside into the
chambers, T and T'. The pipes, O and O', and the valves, I and I',
connected with a blower, serve for the same purpose. The pipes, P and
P', and their valves, J and J', lead a current of steam. The conduits, Q
and Q', and their valves, K and K', direct the gases toward the
purifiers and the gasometer. Finally, the pipes, R and R', provided with
valves, L and L', are connected with a chimney.

The generator, A, is provided at its upper part with a feed hopper. The
doors, S and S', of the ash box close the apertures through which the
ashes are removed.

When it is desired to use the apparatus, the pipes, P, Q, and R, are
closed by means of their valves, J, K, and L, and the valve, I, of the
pipe, O, is opened. The pipes, M and N, are likewise closed, while the
flue, E, is opened. On the other side of the generator the reverse order
is followed, that is to say, the flue, E', is closed, the pipes, M' and
N', are opened, the pipes, O', P', and Q', are closed, and R' is opened.

A current of air is introduced through the pipe, O, and this traverses
the regenerators, B, enters the chamber, T, and the generator, A,
through the flue, E. As this air rises through the mass of incandescent
fuel, its oxygen combines with an atom of carbon and forms carbonic
oxide. This gas that is disengaged from the upper part of the fuel
consists chiefly of nitrogen and carbonic oxide, mixed with volatile
hydrocarburets derived from the fuel used. T