English: "The Stone Wireless Telegraph System", Electrical Review, October 24, 1903, page 594. "a is a source of alternating current; k is a controlling key; M is a transformer for charging the condenser C; s is a discharge gap, and L a variable inductance for tuning. I(1) is the primary of a transformer, the secondary of which I(2) is connected in the aerial wire. When the key is closed the condenser is charged and discharges across the spark-gap through the oscillating circuit sI(1)LC. This circuit is so constructed that these oscillations are harmonic and, by means of the transformer M, they impress forced harmonic vibrations on the aerial wire. These are radiated through space and received by a similar arrangement of circuits, as shown in Fig. 2."