The most exhaustive search failed to bring anything to light respecting the missing officer. The sentry at the last post he had visited had observed nothing singular in his manner. The next post was three hundred yards away, but, although it was a dark night, the officer could not have missed his way. There was a sharp drop in the ground beyond the line that he would traverse, and as the route was the same that had been used for many months, it was scarcely possible that anyone could miss it. The idea that Carlists could have come down from their entrenchments, the nearest of which was four hundred yards away, and captured him, without the sound of a struggle reaching the ears of the sentries to the right or left, seemed hardly possible. Some suggested that he might have gone suddenly out of his mind, and wandered down into the town or to the bank of the Urumea, and there fallen in, but this seemed to all to be wildly improbable.
The officer's letters and papers were examined, but nothing whatever was found that could in the slightest support the idea that he had committed suicide. There was nothing to do but to enter his name upon the list of missing, and hope that he would yet turn up some day and explain the mystery.
"It is your turn for the night duty, Hallett," Sinclair said to him three days after the strange disappearance of Maltravers.
"Yes, I know that my turn for duty begins this evening."
"Well, keep a sharp look-out, old fellow; we don't want any more mysterious disappearances in the regiment."
"No; one is more than sufficient. I have been over the ground half a dozen times during the past three days in the hopes of finding some sort of clue, but without the least success. Perhaps as I go round to-night some bright idea may strike me. Of one thing," he said with a laugh, "you may be perfectly sure: that is, that if I don't turn up in the morning it will be neither desertion, suicide, nor insanity."
"No," Sinclair said; "I should certainly never suspect you of any one of the three."
The others laughed. "You certainly did your best to save your life on board that boat, so we will put suicide out of the question. As to desertion and lunacy, I think they may be equally barred. If you are missing, I shall say that the pixies have carried you off."
"Yes; I think you can safely put it down to that."
After mess was over, Arthur took his pistols and sword and started to the house that was used as the rendezvous of the officers on duty for the night, made his usual visit to the outlying posts along a portion of the line some three-quarters of a mile in extent, and returned. A few minutes before twelve he again started on the same tramp, his companion on duty going in the other direction. Nothing unusual happened until he was half-way along; then, as he passed a ruined hut, he suddenly fell, stunned by a heavy blow from behind. He knew nothing for some time, then he felt dimly conscious that he was being carried along. Reviving consciousness showed him that there were two men at his arms and two at his legs, and that a cloak or some other woollen garment was wrapped round and round his head, and something thrust into his mouth. All this was taken in little by little, for his head buzzed and ached from the blow that had fallen upon it.