Abstract: A hand-operated portable electric ignition device for the ignition of gas comprises within an insulating housing means for producing from a battery relatively high voltage alternating current pulses in response to the operation of a manually-operable switch, said means including a transistor oscillator circuit, rectifying means for rectifying the alternating current pulses for charging a capacitor and means arranged to conduct to provide for the discharge of the capacitor through the primary of a transformer in the output circuit of which is a spark gap across which sparking occurs when the charge voltage on the capacitor reaches a predetermined value.

Abstract: A vacuum furnace in which work loads are periodically introduced and processed therein without breaking the vacuum within the furnace heating chamber and including spaced door assemblies between which chambers are defined for effectively isolating the work loads during the introduction and discharge therefrom, the apparatus further including transfer mechanisms that are sequentially operated in timed relation with the door assemblies and in accordance with the heat treating cycle of the furnace for moving work loads through the various stations in the furnace.