At other times again the motive force seemed to be so extraordinarily active that, the sound deflector notwithstanding, the instrument captured and transmitted a thousand noises which are not to be heard by the unobservant listener, or in some cases by any human ear.
Weird enough these noises were at times.

Like great sighs they came, like the moan of the breeze brought from an infinite distance, like mutterings and groanings arisen from the very bowels of the earth.

Then there were the splash or boom of the waves, the piping of the sea-wind, the cry of curlew, or black-backed gulls, all mingled in one great and tangled skein of sound that choked the voice of the speaker, and in their aggregate, bewildered him who hearkened.
These, and others which need not be detailed, were problems that had to be met, necessitating many more experiments.

Thus it came about that through most of the short hours of winter daylight Morris and Stella found themselves at their respective positions, corresponding, or trying to correspond, through the aerophones.

If the weather was very bad, or very cold, Morris went to the dead Church, otherwise that post was allotted to Stella, both because it was more convenient that Morris should stay in his laboratory, and by her own choice.
Two principal reasons caused her to prefer to pass as much of her time as was possible in this desolate and unvisited spot.