The wire is made positive, and the signal to be demodulated is applied directly to it; a small (about 5 ml) platinum cup filled with either sulfuric or nitric acid completes the headphone circuit, and is also connected to ground to complete the signal circuit.
A wire is used as the positive terminal, and the signal intended for demodulation is applied directly to it; a tiny (about 5 ml) platinum container filled with either sulfuric or nitric acid completes the headphone circuit, and is also connected to ground to complete the signal circuit.