(4) Losses Due to Unconsumed Gases Escaping Through the Smoke Stack, 10%.

I trust what I have already said under the Theory of Combustion will help the firemen in realising that a pronounced saving could easily be brought about by them. But on the accepted principle that theory is only the servant of practice I would urge upon the drivers their duty to carefully watch the firemen and coach them in the fine art of firing. Many of the older drivers are too apt to forget the period of their own apprenticeship—that they themselves probably were taught much that they know to-day by the kindly help of the drivers with whom they served in days gone by.