He went over to the outer door when he had eaten his chocolate, and examined that at his leisure. That, in lesser degree, was set into the wall as strongly as the inner one. He saw no means of opening it from the inside: it was evidently secured by a patent mechanical lock of which Joseph Chestermarke presumably carried the one key. He turned from it to look more closely at a shelf of books and papers which projected from the wall above the table. Papers and books were all of a scientific nature, most of them relating to experimental chemistry, some to mechanics. He noticed that there were several books on poisons; his glance fell from those books to various bottles and phials on the table, fashioned of dark-coloured glass and three-cornered in shape, which he supposed to contain poisonous solutions. So Joseph dabbled in toxicology, did he? thought Neale-in that case, perhaps, there was something in the theory which had been gaining ground during the last twenty-four hours-that Hollis had been poisoned first and thrown into the old lead-mine later on. And-what of the somebody, Horbury or whoever it was, that lay behind that grim-looking door? Neale had never heard a sound during the time which had elapsed before he dropped asleep, never a faintest rustle since he had been awake again. Was it possible that a dead man lay there-murdered?
A cheerful chirping and twittering in the space behind him caused him to turn sharply away from the books and bottles. Then he saw that he was no longer alone. Half a score sparrows, busy, bustling little bodies, had come in by the open window, and were strutting about amongst the grey ashes in front of the furnace.
Neale's glance suddenly fell on the loaf of bread, close at hand on the edge of the table, and on the knife which lay by it. Mechanically, without any other idea than that of feeding the sparrows and diverting himself by watching their antics, he picked up the knife, quietly cut off a half-slice of the loaf, and, crumbling it in his fingers, threw the crumbs on the floor. For a minute or two he watched his visitors fighting over this generous dole; then he turned to the shelf again, to take down a book, the title of which had attracted him. Neale was an enthusiastic member of the Territorial Force, and had already gained his sergeant's stripes in the local battalion; he was accordingly deeply interested in all military matters-this book certainly related to those matters, though in a way with which he was happily as yet unfamiliar. For its title was "On the Use of High Explosive in Modern Warfare," and though Neale was no great reader, he was well enough versed in current affairs to know the name of the author, a foreign scientist of world-wide reputation.
He opened the book as he stood there, and was soon absorbed in the preface; so absorbed indeed, that it was some little time before he became aware that the cheerful twittering behind him had ceased. It had made a welcome diversion, that innocent chirping of the little brown birds, and when it ceased, he missed it. He turned suddenly-and dropped the book.
Seven or eight of the sparrows were already lying on the floor motionless. Some lay on their sides, some on their backs; all looked as if they were already dead. Two were still on their feet; at any other time Neale would have laughed to see the way in which they staggered about, for all the world as if they were drunk. And as he watched one collapsed; the other, after an ineffective effort to spread its wings, rolled to one side and dropped helplessly. And Neale made another turn-to stare at the loaf of bread and to wonder what devilry lay in it. Poison? Of course it was poison! And-what of this man in that jealously guarded room, behind that steel door? Had he also eaten of the loaf?
He turned to the sparrows again at last, stood staring at them as if they fascinated him, and eventually went over to the foot of the furnace and picked one up. Then he found, with something of a shock, that the small thing was not dead. The little body was warm with life; he felt the steady, regular beating of the tiny heart. He laid the bird down gently, and picked up its companions, one by one, examining each. And each was warm, and the heart of each was beating. The sparrows were not dead-but they were drugged-and they were very fast asleep.
Neale now began to develop theories. If a mere tiny crumb of that loaf could put a sparrow, a remarkably vigorous and physically strong little bird-to sleep within a minute or two, what effect would, say, a good thick slice of it produce upon a human being? Anyway, the probability was that the captive in that room was lying in a heavily drugged condition, and that that was the reason of his silence. He would wake-and surely some sound, however faint, would come. He himself would wait-listening. The morning wore on-he waited, watched, listened. None came-nothing had happened. He ate more of his chocolate. He read the book on explosives. It interested him deeply-so deeply that in spite of his anxiety, his hunger, his uncertainty as to what might happen, sooner or later, he became absorbed in it. And once more he was called from its pages by the sparrows.
The sparrows were coming to life. After lying stupefied for some four or five hours they were showing signs of animation. One by one they were moving, staggering to their feet, beginning to chirp. And as he watched them, first one and then the other got the use of its wings; and, finally, with one consent, they flew off to the open window-to disappear.
Thereafter, Neale listened more keenly than ever for any sound from that mysterious room. But no sound came. The afternoon passed wearily away; the light began to fail, and at last he had to confess to himself that the waiting, the being always on the alert, the enforced seclusion and detention, the desire for proper food and drink-especially the latter-was becoming too much for him, and that his nerves were beginning to suffer. Was Joseph Chestermarke never coming? Had he gone off somewhere?-possibly leaving a dead man behind, whose body was only a few yards away. There was no spark of comfort visible save one. Old Rob Walford would be home late that night from Wymington-sooner or later he would hear of Neale's disappearance and he would sharpen his naturally acute wits and come to the right conclusion. Yet-that might be as far off as tomorrow.
As the darkness came, Neale, now getting desperate for want of food, was suddenly startled by two sounds which, coming abruptly at almost the same time, made him literally jump. One-the first-was a queer thump, thump, thump, which seemed to be both close at hand and yet a thousand miles away. The second was Joseph Chestermarke's voice in the garden outside-heard clearly through the open window. He was bidding somebody to tell a cab-driver to wait for him at the foot of the bridge. The next minute, Neale heard a key plunged into the outer door-before it turned, he, following out a scheme which he had decided on during his long watch, had leaped behind the screen that stood near the furnace. Ere the door could open, he was safely hidden-and in that second he heard the thumping repeated and knew that it came from the inner room.