[Illustration: APPARATUS FOR MAKING OXYGEN.]
We give herewith details of the plant now working at Westminster. It
is exceedingly simple. On the left of the side elevation and plan are
shown the retorts, on the right is an arrangement of pumps for
alternately supplying air under pressure and exhausting the oxygen
from the retorts. As is shown in the plan, two sets of apparatus are
worked side by side at Westminster, the seventy-two retorts shown in
the drawings being divided into two systems of thirty-six. Each system
is fed by the two pumps on the corresponding side of the boiler. Each
set of retorts consists of six rows of six retorts each, one row above
the other. They are heated by a small Wilson's producer, so that the
attendant can easily regulate the supply of heat and obtain complete
control over the temperature of the retorts. The retorts, A, are made
of wrought iron and are about 10 ft long and 8 in. diameter.
Experience, however, goes to prove that there is a limit to the
diameter of the retorts beyond which the results become less
satisfactory. This limit is probably somewhat under 8 in. Each retort
is closely packed with baryta in lumps about the size of a walnut. The
baryta is a heavy grayish porous substance prepared by carefully
igniting the nitrate of barium; and of this each retort having the
above dimensions holds about 125 lb.
Pages:
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94