substances that cause asthma and similar conditions were to take it into his head to kill another human being, I said, and chose a victim with a known sensitivity to, say, pollen, and a history of asthma, how would he induce the phenomenon known as acute respiratory shock? By grinding the pollen to a fine powder, said my adviser and then taking a very small amount, as little as a tenth of a milligram, and injecting it into the victim, perhaps secreted in some other substance administered in the course of treatment. Then if two weeks later he were suddenly exposed to a slightly larger quantity of the substance, say a milligram, he would die within five minutes. The amounts involved would be so small as to be impossible to detect in a post mortem. Did the second quantity of the substance have to be introduced by means of an injection, I asked? No, said he, certain substances are readily absorbed by skin tissue-nettle leaf irritant, for example, or pollen.’
‘This is all very plausible,’ said Prothero, ‘but when Guy died we were not in a bed of nettles, Sergeant, nor were we coating ourselves with pollen in the hotel garden. So far as I can recollect, there were not even any flowers in the lounge.’
‘I established that, sir. Went over everything I could think of until I was ready to give up. Then, as sometimes happens, I was thinking of something quite unconnected with the case, when the very thing I needed to know flashed across my mind. It was the statement the inspector made after I arrived and found you both there with Guy’s body. He
‘You’ve had the contents of the snuff-box analysed, I have no doubt,’ said Prothero.
‘I have, sir, and as you very well know there ain’t a microscope invented with sufficient power to detect a quantity of pollen as small as that, nor a chemical test to prove its presence. It’s as neat a way of ending a fellow- human’s life as I’ve ever come across. A doctor’s way.’
‘A father’s,’ said Prothero, after a pause, ‘and not neat, Sergeant.’
‘The boy would have killed again if he had lived,’ said Cribb. In their context the words were reassuring. For the first time all pretence between the two men had been abandoned. They observed each other with candour, if not respect.
‘There is a saying of Hippocrates, the founder of our profession,’ said Prothero, ‘“Extreme remedies are most appropriate for extreme diseases”. Believe me when I tell you that I did all I could for Guy while he was alive. At the last, I had to ask myself what future there was for him. I know of other cases, Sergeant, poor wretches with the same dreadful impulse for violence who are kept behind locked doors by devoted parents. Can you imagine what will happen when one of them one day finds a way to slip the latch-for they are intelligent beings as Guy was? The mayhem and the carnage will be beyond belief, Sergeant, striking terror into people’s hearts long after the poor demented creature is recaptured by the police or his wretched family. Am I exaggerating?’
‘I hope so, sir,’ said Cribb quietly. ‘I think we’d better move in the direction of the station.’
Prothero raised his eyebrows questioningly. ‘Railway-or police?’
‘I’d never be able to prove my case in court,’ said Cribb with a slight smile. ‘Damned lawyers aren’t going to get a conviction out of nothing more substantial than an extra week in Brighton. . Unless you’ve decided to make a confession. But, as I said, I didn’t bring a man with me, or the handcuffs, and it’s devilish hard to hear anything anyone says on those confounded trains. I think we’ve just time to catch that 4.23.’
Albert Moscrop finished polishing the latest example of his handiwork, a small, brass telescope with a magnification of four diameters. It represented some three weeks’ work, mainly in the evenings, after the shop was closed. He had begun on the day when he had read the newspaper report of the inquest on Bridget. She had been murdered, it had said, by a person or persons unknown, but it was understood that the police had indicated that there was nothing to be gained from further inquiries into the case.
He snapped the telescope shut and placed it on the tissue paper in a narrow wooden box on the table in front of him, making sure that the engraved name ‘Jason’ was uppermost. Then he closed the box, wrapped it, addressed it and affixed a stamp. As an afterthought, before he took it to the post-office, he turned the parcel over and wrote on the reverse, in small, neat letters,