"Pray what might that be, Parker?"
"I have only just thought of it Could it not be that you were correct about Miss Smithers? That she committed the fatal deed on impulse and that young Fernchurch is shielding her?"
Pons flicked his spent match behind him and looked at me sharply.
"Well said, Parker. That is distinctly ingenious. Your gray cells are working at last. You may have hit close to the truth without knowing it. Ah, here is the inspector and our client himself."
The two familiar figures had appeared underneath the archway where we shortly joined them, before Pons led the way out to the tower on the other side.
"Well, Mr. Pons, I trust you have come to some conclusions. We cannot keep Mr. Fernchurch here hovering under a cloud."
"Quite right, Inspector," said Pons briskly. "I have followed some lines of inquiry, it is true. But there is some connecting link which eludes me for the moment. I need just that one touch to prove my theory. Until then I prefer not to commit myself."
"Why, Pons," said I. "It should be easy enough. You need only carry out your pebble experiment from the young lady's window, yonder. The shorter, distance would not matter so much with such a heavy hammer but would be more accurate, surely."
Solar Pons stared at me as though I had said something of momentous importance. His dancing eyes shot upward to where I had indicated the open window of the Smithers's sitting room.
"My dear Parker, you are, as I said earlier, a veritable transmitter of light! Here the matter has been staring me in the face, and I need only have taken two physical steps to corroborate my theory. If ever I have been obtuse, it is on this occasion. Come, Parker!"
My companions stared at him as though he had gone mad, but Pons had already turned on his heel and was running through the arch. He ascended the tower steps two at a time so that he swiftly outdistanced me. By the time I had puffed my way to the top landing he was already being admitted to their private quarters by Professor Smithers and his daughter.
The curator had an abashed look on his face as he caught sight of us, but he controlled himself and in quite a gracious manner invited us all in.
"This will not take a moment," said Pons, once we were inside the sitting room. "It is just a small point of corroborative evidence, but which is nevertheless vital. My client's innocence depends upon it."
"Certainly, Mr. Pons. Whatever you wish."
The professor's amazement was written large upon his features, and he was even more astonished when Pons went across to the open window. A few seconds later there were gasps as he vaulted through, to land safely on the planked scaffolding that was placed just, below and to the right of the window.
"Do be careful, Mr. Pons," said Miss Smithers in worried tones.
"Do not fear, young lady," said Pons, kneeling now and intent on the windowsill of the sitting room. He had his lens out and leaned over dangerously, working his way back and forth along the sill before turning his attention to the stones beneath. There was a muffled exclamation and I saw that his face was completely transformed.
"Ah, just as I thought. Allow me to congratulate you, Mr. Fernchurch."
"On what, Mr. Pons?"
"On your innocence and on the clearing of the capital charge against you."
"Oh, come, Mr. Pons," said Inspector Fitzjohn in a skeptical voice. "That is rather a sweeping statement."
"Just fetch me a large mirror, Miss Smithers," said Pons calmly. He sat on the planked scaffolding, dangling his legs in space and looking perfectly at home until the girl returned with the article he had requested. He took the mirror from her and held it so that we could see a portion of the stonework beneath the window sill.
"There, Inspector. Do you not see?"
"I see a large gash in the stonework, Mr. Pons," said Fitzjohn cautiously.
"Exactly! And the mark is new. It indicates considerable force, for these centuries-old stones are hard as iron. But there is one conclusive point, which you cannot very well see from here. It indicates that the blow was in an upward direction!"
"What on earth are you talking about, Mr. Pons?"
Professor Smithers could not keep the irritation from his voice — so cryptic had Pons been that I almost sympathized with him. Pons handed the mirror back in through the window to the girl, with a flourish, and then followed himself, dusting the knees of his trousers.
"But what does it all mean, Mr. Pons?" asked Fernchurch, his puzzled eyes seeking the girl's.
"It means, Mr. Fernchurch, that Sebastian Bulstrode killed himself!"
Pons chuckled at the gasped incredulity from the circle of people around him.
"You cannot mean it, Mr. Pons," stammered Professor Smithers. "Suicide?"
Pons shook his head.
"But you aptly named the weapon, Professor. The Hammer of Hate you called it, did you not? We had better just sit down while I explain."
When we were seated comfortably near the fireplace, Pons went to stand by the mantel, his eyes conveying a faraway look.
"When Mr. Fernchurch came to me at Praed Street with his distressing story, I rapidly came to the conclusion, from his manner and general demeanor, that he was speaking the truth. He had been caught, as it were, by a large number of people at the top of the tower a few minutes after Bulstrode had been struck down and killed by this heavy iron hammer we have heard so much about. The major difficulties lay in motive and method. First, Mr. Fernchurch had some motive. Rivalry over Miss Smithers, quarrels and — according to some local people — an actual incident when the two men almost came to blows."
"Quite untrue, Mr. Pons," said Fernchurch hotly. "It was mere gossip."
Solar Pons inclined his head.
"I quite agree, Mr. Fernchurch. I have heard a great deal of you about bars and streets of Maldon. I have long ago learned to ignore gossip, but it can be revealing on occasion. Very rarely it can also help to clear absurdities in the matter — and one which you would have done well to have grasped, Parker — was the obvious difficulty, not to say almost impossibility of the method used. I made my own experiments by dropping pebbles from the tower top onto a large piece of sacking. Now, although the sacking was a great deal larger than a man's head, I succeeded in hitting it only seven times out of thirty."
Pons paused and relit his pipe, puffing out blue clouds of aromatic smoke.
"So that at an early stage I had discounted premeditated murder in Mr. Fernchurch's case, or indeed his implication in the matter in any way. He was merely unfortunate in that he was at the wrong place at the wrong time. What compounded the difficulties was that Miss Smithers had been delayed in meeting him by some discussion between her and her father on her choice of fiancée. Had both been on the tower top, Miss Smithers could have provided powerful corroborative evidence of his innocence and avoided a great deal of unfortunate publicity."
"I take back nothing I have said," snapped Professor Smithers.
"I did not ask you to," he said gently. "The second difficulty I mentioned was the hammer. It was made of iron, covered with stone dust, and the shock of it first striking Mr. Bulstrode's skull and then rebounding to the ground shook the dust from it, so that no usable fingerprints were found That could not possibly have been foreseen by any potential murderer."
You are forgetting the professor and the other possible suspects, Pons," I could not help putting in.
Solar Pons took the pipe out of his mouth and shook his head.
"I am forgetting nothing, Parker. It is true that there were complications. Professor Smithers could, no doubt, have gained access to the tower from this room and by means of the scaffolding have dropped the hammer onto Bulstrode. But I think it hardly likely, particularly as he could have obtained more accurate results from the window of this room."