A. The safety valve. To allow the oil in pipes to be consumed and to see
that this valve is in working order.
50. Q. Should safety valve fail to shut off the flow of oil in such
cases would it be safe to rely on the firing valve to shut off the fire?
A. No. The main valve should then be closed.
51. Q. Should the firing valve be depended upon to shut off the fire at
any time? Why?
A. No. From constant use they are frequently leaking and the trouble is
not detected while in use, and again there is always danger of the
handle being moved by workmen or others about the cab.