Hanslet rather perfunctorily asked one last question. ‘There was no suggestion that Harleston might lose his job, I suppose?’
Mr Knott shook his head. ‘Good heavens, no!’ he replied. ‘There was no reason why Harleston should not have stayed with us till the day of his death. We always found him a very useful man, so useful that we paid him a special bonus of a hundred pounds at the beginning of this year.’
From Chancery Lane Hanslet returned to Scotland Yard. On his desk he found a message awaiting him. It was as follows.
‘Dr Priestley would be glad if you could find it convenient to dine with him this evening. Oldland, who would like to see you, will be present.
H. MEREFIELD.’
Hanslet smiled. ‘So the Professor’s on the job already, is he?’ he muttered. ‘You bet I’ll go. But I’m afraid there isn’t enough meat in this case to suit the old boy’s appetite.’
4
Dr Priestley, who lived in a spacious if rather gloomy house in Westbourne Terrace, was, in his own line, a distinguished scientist. His name was hardly familiar to the general public, but to his fellow-savants he was very well known indeed. He was a man of considerable means and since his retirement from a professorship, he had devoted himself to scientific criticism. His articles and monographs, though usually couched in somewhat acrid terms, were treated with profound respect in the learned world.
But in addition to his scientific employment, he had a hobby. This hobby, which he liked to pursue in secret, was criminology. He maintained that criminology, properly treated, presented problems of absorbing interest to the scientist. Many years ago he had made Hanslet’s acquaintance. They had become fast friends and Hanslet got into the habit of laying his more difficult cases before the acute brain of the professor.
It happened that Dr Oldland was one of Dr Priestley’s oldest acquaintances. It was natural therefore that he and Hanslet should meet frequently at the professor’s house. The reason for the present invitation was fairly obvious. Oldland had told the professor about his experience of that morning, and some feature of his account had interested the latter. In any case dinner at the house in Westbourne Terrace was an event to be remembered. Hanslet was always ready to enjoy an excellent meal in such distinguished company.
So that evening at eight o’clock he sat down at the professor’s table. He found himself one of a party of four, the other two being Oldland and Dr Priestley’s secretary, Harold Merefield. The professor never encouraged the discussion of problems during dinner, holding that such a procedure might divert his guests’ attention from their food. It was not until the company was assembled in the study afterwards that he made any reference to the Harleston case.
‘Oldland tells me, Superintendent, that you and he met under rather peculiar circumstances this morning,’ he remarked.
‘We met because Oldland sent for me,’ Hanslet replied. ‘He had been called in to attend a suspiciously sudden case of poisoning and he seemed to think that I ought to know about it.’
‘It was a devilish awkward,’ said Oldland reminiscently, helping himself to a whisky and soda. ‘There was I, alone in the house with that girl and a remarkably suspicious looking corpse. I didn’t know what the dickens to do. If I went out to call the police I should have had to leave her alone. For all I knew, there might be evidence in the house that she would take the opportunity to destroy. So I hit upon the idea of sending her back to my place for a wholly imaginary black case, and employed her absence in telephoning to you. How did you get on after I left?’
Hanslet laughed. ‘So that was the dodge, was it? I was faced with the same difficulty. I got out of it by sending the girl to the Yard and putting her in charge of young Waghorn. You remember him, I expect, Professor?’
Dr Priestley nodded solemnly. ‘Yes, I remember him in connection with the Threlfall case.’
‘Well, having got rid of her, I started to have a look round,’ said Hanslet. ‘I sent for Dr Bishop, the police surgeon, to lend me a hand. We didn’t have far to look. Harleston’s early tea had been liberally doctored with nicotine.’
‘Nicotine!’ exclaimed Dr Priestley. ‘Why, the presence of the most minute quantity of nicotine would surely be detected by anybody with normal powers of taste and smell?’
‘I should have thought so,’ Hanslet replied. ‘The tea in the pot stank like a rank pipe. But there was the nicotine and there was the man dead of acute poisoning. I shall hear tomorrow what the post-mortem has revealed.’
‘I can tell you that now,’ said Oldland quietly. ‘The coroner asked Bishop to carry it out, and he, knowing that I had been called in, invited me to attend. At my suggestion we called in Grantham, the pathologist from the Home Office. The three of us set to work and, if you’re interested, I can tell you what we found.’
‘Not unnaturally, I’m profoundly interested,’ said Hanslet.
Oldland grinned. ‘Well, we found the nicotine all right,’ he said slowly. ‘There’s not a shadow of doubt that nicotine poisoning was the cause of Harleston’s death. But curiously enough, we didn’t find it where you might have expected. In his tummy, that is.’
‘Well, where did you find it?’ Hanslet asked impatiently.
‘Absorbed into his system. You may have noticed that the chap had a piece of sticking plaster on his face, suggesting that he had cut himself while shaving. Well, we removed that and found a nice clean cut underneath it. From the appearance of the edges of the cut we had no doubt that it was through this that the nicotine had been absorbed.
‘Now nicotine is one of the most virulent poisons known. Cases of fatal poisoning have been due to nicotine being absorbed through the unbroken skin. A very small quantity taken internally produces rapid death. Priestley will bear me out in that.’
‘Nicotine is known to be extremely rapid in its action,’ Dr Priestley remarked. ‘In the celebrated case of Count Bocarmé, who poisoned his wife’s brother with nicotine which he prepared for the purpose, death took place in five minutes.’
‘Since in this case the poisoning was by absorption, death was rather less rapid than that,’ said Oldland. ‘How the nicotine came in contact with the cut, I can’t say.’
Hanslet looked in bewilderment from one to the other. ‘There was nicotine in the teapot,’ he said stubbornly. ‘Somebody drank a cup of tea from that pot and there seems no doubt that it was Harleston.’
Oldland shrugged his shoulders. ‘I can’t help it,’ he replied. ‘There was practically no trace of nicotine in the man’s stomach. Grantham carried off the contents for analysis, of course, but I’m willing to bet anything you like that he won’t find more than a trace. Whereas the tissues in the neighbourhood of the cut were literally impregnated with nicotine.’
‘You mean that he can’t have drunk the tea?’ Hanslet asked.
‘Not if it was so saturated with nicotine as you suggest. I may as well say that Bishop told me about the tea, and the absence of nicotine in the stomach troubled him as much as it does you. The only theory he could suggest was this. Harleston had not drunk the tea owing to its offensive taste and smell. On the other hand, after he had cut himself, he applied some of the leaves to his face in an attempt to stop the bleeding. I believe that people do employ tea-leaves for that purpose.’
‘Well,’ Hanslet exclaimed, ‘somebody must have put it there,’ Oldland agreed readily enough. ‘But where did she get it from? That’s the question.’
‘What is nicotine used for?’ Hanslet asked.
Dr Priestley glanced towards his secretary. ‘Will you get down the Chemical Encyclopaedia, please, Harold?’ he said. ‘Thank you. Now will you turn to the article on nicotine, and extract from it the answer to the Superintendent’s