Sorely tempted as I was to signal further, I refrained for fear of arousing suspicion, and, actuated by patriotic motives, we agreed at once to prosecute our inquiry further, and then leave it to "the proper authorities" to deal with the matter. Through the whole of that night--an intensely cold one--we remained on watch upon one of the highest points in Surrey, a spot which I do not here indicate for obvious reasons--and not until the grey dawn at last appeared did we relinquish our watchfulness. All next day, assisted by the same young officer who had first noticed the unusual lights, I spent in making confidential inquiry regarding the mysterious house and elicited several interesting facts, one being that the family, who were absent from the house showing the lights, employed a servant who, though undoubtedly German--for, by a ruse, I succeeded in obtaining the address of this person's family in Germany--was posing as Swiss. That a brisk correspondence had been kept up with persons in Germany was proved in rather a curious way, and by long and diligent inquiry many other highly interesting facts were elicited. With my young officer friend and a gentleman who rendered us every assistance, placing his house and his car at our disposal, we crept cautiously up to the house in the early hours one morning, narrowly escaping savage dogs, while one adventure of my own was to break through a boundary fence, only to find myself in somebody's chicken-run! That night was truly one of adventure. Nevertheless, it established many things--one being that in the room whence the signals emanated was a three-branch electrolier with unusually strong bulbs, while behind it, set over the mantelshelf, was a mirror, or glazed picture, to act as a reflector in the direction of London. The signals were, no doubt, made by working the electric-light switch. The following night saw us out again, for already reports received had established a line of signals from a spot on the Kent coast to London and farther north, other watchers being set in order to compare notes with us. Again we watched the beacon-light on the mysterious house. We saw those mysterious letters "S.M."--evidently of significance--winked out in Morse, and together we watched the answering signals. All the evening the light remained full on until at 1.30 a.m. we once more watched "S.M." being sent, while soon after 2 a.m. the light went out.