The projectoscope relays, swinging in wide arcs, recorded little of value except at the ends of their swings.
Thus far we have referred to two systems, one the neutral or differential duplex, and the other the combination of the neutral and polar relays, making a diplex system.
Gone was the joy of our faces, grim and haggard and pale; The heedless mirth of the shipboard was changed to the care of the trail. We flung ourselves in the struggle, packing our grub in relays, Step by step to the summit in the bale of the winter days.
If both transmitters be closed simultaneously, both batteries will be placed to the line, which would practically result in doubling the current in each of the main-line coils, in consequence of which both relays are energized and their armatures attracted through the operation of the keys at the distant ends.