pointed out in its use as a fire-proofing material perhaps also exist, to
a certain degree, in its other applications. In painting upon glass, for
instance, it is asserted that the brilliancy and finish of ordinary
vitrified colors cannot be obtained.--_Glassware Reporter._

* * * * *




THE JET VENTILATOR.


[Illustration: KORTING'S JET VENTILATOR.]

Messrs. Korting bros., of London, induced by the interest that has been
directed to the separate ventilation of mines in which fire-damp is apt
to form, have adopted for this purpose their jet ventilator. The
instrument, which we illustrate in Fig. 1, has been, we understand,
considerable simplified, and adapted for the special object in view. The
ventilators are worked by compressed air, and are so arranged that,
without stopping their action, the quantity of air they deliver can be
rapidly increased or diminished. This ample power of control has been
arranged for by the special wish of the mining authorities, who wish to
regulate the ventilation according to the development of fire-damp or the
greater or less number of men at work. Under circumstances of this kind
the quantity of air taken into the mine can be changed instantly. The
illustrations, Figs. 2, 3, and 4, show different modes of fixing the jet
ventilator. In Fig. 2, it is arranged to blow the air forward; in Fig. 3,
it is shown exhausting the air; and in Fig. 4, it is represented as