the housekeeper's apology."
Wells tutted. "Those wretched eggs again!"
"At any event," Bryson said, "I was only gone a few minutes. But by the time I returned Tarquin had sliced clean through the main support. Then the shearing began."
"So you clearly identified the gas line to Tarquin."
"I told you. I pointed to it."
"And there is no way he could have mixed it up with the support cable?"
He raised his eyebrows. "What do you think?"
I scratched my head. "Is it possible he caught the support somehow with the torch, as he was working on the gas feed?"
He laughed; it was a brief, ugly sound. "Hardly, Doctor. The support is about four feet from the air line. He had to turn round, and stretch, and keep the torch there, to do what he did. We can go up to the gantry and see if you like." He seemed to lose his confidence. "Look, Mr Holmes, I do not expect you to believe me. I know I am only an engineer, and Tarquin was Ralph's brother."
"Bryson—"
"But there is no doubt in my mind. Tarquin quite deliberately cut through that support, and ended his brother's life."
There we left our inquiries for the day.
I fulfilled Holmes's request regarding the dog Sheba. On a cursory inspection I found the poor animal's limbs to be spindly and crooked from so many breaks. I collected a sample of her urine and delivered it to the Chippenham general hospital, where an old medical school friend of mine arranged for a series of simple assays. He had the results within the hour, which I tucked into my pocket.
I rejoined my companions, who had retired to the "Little George" hostelry in Chippenham for the evening. They had been made welcome by a broad-bellied, white-aproned barman, had dined well on bread and cheese, and were enjoying the local ale (though Holmes contented himself with his pipe), and talking nine to the dozen the while.
"It is nevertheless quite a mystery," said Wells, around a mouthful of bread. "Has there even been a murder? Or could it all be simply some ghastly, misunderstood accident?"
"I think we can rule that out," said Holmes. "The fact that there are such conflicts between the accounts of the two men is enough to tell us that something is very wrong."
"One of them—presumably the murderer—is lying. But which one? Let us follow it through. Their accounts of the crucial few seconds, when the cable was cut, are ninety per cent identical; they both agree that Bryson had issued an instruction to Tarquin, who had then turned and cut through the support. The difference is that Bryson says he had quite clearly told Tarquin to cut through the air line. But Tarquin says he was instructed, just as clearly, to slice through what turned out to be the support.
"It is like a pretty problem in geometry," went on Wells. "The two versions are symmetrical, like mirror images. But which is the original and which the false copy? What about motive, then? Could Tarquin's envy of his brother—plain for all to see—have driven him to murder? But there is no financial reward for him. And then there is the engineer. Bryson was driven to his dalliance with Jane Brimicombe by the tenderness of his character. How can such tenderness chime with a capability for scheming murder? So, once again, we have symmetry. Each man has a motive—"
Holmes puffed contentedly at his pipe as Wells rattled on in this fashion. He said at last, "Speculations about the mental state of suspects are rarely so fruitful as concentration on the salient facts of the case."
I put in, "I'm sure the peculiar circumstances of the death had something to do with the nature of the Inertial Adjustor itself, though I fail to understand how."
Holmes nodded approvingly. "Good, Watson."
"But," said Wells, "we don't even know if the Adjustor ever operated, or if it was another of Ralph's vain boasts—a flight of fancy, like his trip to the Moon! I still have that vial of Moon dust about me somewhere—"
"You yourself had lunch in the chamber," Holmes said.
"I did. And Ralph performed little demonstrations of the principle. For instance: he dropped a handful of gravel, and we watched as the heaviest fragments were snatched most rapidly to Earth's bosom, contrary to Galileo's famous experiment. But I saw nothing which could not be replicated by a competent conjurer."
"And what of the mice?"
Wells frowned.
"They were rather odd, Mr Wells," I said.
"We can imagine the effect of the distorted gravity of