Oldland nodded. ‘That’s right,’ he said. ‘Almost every gardener uses nicotine in some form or another. Fruit growers especially. They make a wash from it with which they spray their trees.’
Hanslet suddenly stiffened in his chair. ‘Fruit growers!’ he exclaimed. ‘Do they, by jove! I learnt this morning that young Philip Harleston is the manager of a fruit farm.’
‘That certainly suggests the possible source of the nicotine,’ Oldland remarked. ‘You found some more of the stuff mixed with the girl’s eau-de-Cologne, Bishop tells me.’
‘Yes, on her dressing table. I’ve been wondering whether the mixture was made in the hope that the eau-de-Cologne would drown the smell of the nicotine.’
‘It’s possible,’ said Oldland shortly. ‘By the way, did the girl say anything to you about a man at the door?’
Hanslet appeared rather astonished at this question. ‘Oh, she mentioned him to you, did she?’ he said. ‘I was inclined to think that rather nebulous individual was an afterthought.’
‘She didn’t mention him to me until we had had some conversation together. And then she mentioned him quite suddenly, and I think genuinely.’
‘You’d have thought it would have been the first thing she would have talked about,’ Hanslet objected. ‘Dash it all, a stranger on the doorstep just at the critical moment when she was going out to fetch the doctor! According to her account, this stranger volunteered to come in and look after her brother while she was away. Yet, when she returned, he wasn’t there and she showed no astonishment.’
‘Oh, I don’t know,’ Oldland replied. ‘You must remember her mind was fully occupied with her brother. The momentary incident of the stranger might well have slipped her memory.’
‘Well, the stranger, even though he may have been a confederate, cannot have been the actual poisoner,’ said Hanslet. ‘Unless he was in the house earlier in the morning unknown to its occupants, and I don’t see how that can have happened. No, I’m afraid the matter’s plain enough. Janet Harleston poisoned her half-brother, possibly at the instigation of Philip.’
Dr Priestley had been listening attentively to this conversation. ‘Do you not think, Superintendent, that you are accepting things at their face value without adequate investigation?’
‘Well, Professor, I was inclined to think at first that things were too easy,’ Hanslet replied. ‘But then, I made some inquiries into the question of motive. I went to see the family solicitor. From him I obtained the information that there are only two people who could possibly benefit by Victor Harleston’s death. And those two people are his half-sister and brother.’
Dr Priestley frowned. ‘Benefit financially, I suppose you mean,’ he said. ‘Surely you are not yet sufficiently acquainted with Harleston’s history to state that nobody else might have found his death desirable?’
‘Well no, I suppose I’m not,’ Hanslet replied. ‘But from what I can hear of Harleston, he was a man without any particular history. He seems to have been mean and uncompanionable, but otherwise inoffensive.’
Dr Priestley put the tips of his fingers together, a favourite gesture with him, and stared at the ceiling. ‘It seems to me,’ he said oracularly, ‘that the chief interest of this case lies in the manner by which the poison was administered. It appears to be proved fairly conclusively that the poison was not swallowed, but absorbed through a cut sustained while Harleston was shaving. It appears to me hardly probable that Harleston applied the whole of a cup of tea to his cut. He might have dipped a towel in the tea and dabbed this on his face. But that would account for hardly more than a spoonful of the tea. Yet, I understand, the tea-cup found in his room was nearly empty.’
Hanslet laughed. ‘Perhaps you will remember a case in which you helped me not long ago, Professor,’ he replied. ‘Then you asked me if I had looked for lip marks on a wine glass. I remembered that this morning and I particularly looked for lip marks on the cup. I found them, all right. There’s not a shadow of doubt that the cup had been drunk from. And yet, here is Dr Oldland, assuring us that the poison had not been swallowed.’
‘I do not see that that need present any difficulty,’ said Dr Priestley quietly. ‘If the poison were already in the tea when Harleston poured out his cupful he certainly did not drink it. The post-mortem evidence is conclusive proof of that. On the other hand, if Harleston drank the cup of tea, the poison was not then in it. We should then be driven to explore the possibility of the poison having been added at some later time.’
‘Added later!’ Hanslet exclaimed. ‘When? Why? And by whom?’
Dr Priestley seemed indisposed to reply. It was Oldland who stepped into the breach. ‘I’d hazard a guess to all three parts of your question, Superintendent,’ he said. ‘When, during the period that Janet Harleston was absent from the house on her errand to fetch me. Why, to produce a false impression. The poisoner may not have known that post-mortem examination would enable us to say positively that the poison had not been swallowed but absorbed through the skin. Finally, by whom, suggests a very interesting speculation. What about the man whom Janet met on the doorstep?’
Dr Priestley protested. ‘This is carrying conjecture to an unwarrantable length,’ he said severely.
‘Sorry, Priestley,’ said Oldland contritely. ‘That was a wild bit of guesswork, I’ll admit. But the facts are there and they’ve got to be explained somehow.’
‘They are more likely to be explained by careful investigation than by conjecture,’ Dr Priestley replied. ‘The central point, I still insist, is this. How did the nicotine come in contact with the wound? You have, no doubt, made a careful examination of the house, Superintendent. In the course of that, did you find a bloodstained towel?’
‘No, it’s rather a queer thing, but I didn’t,’ Hanslet replied. ‘I looked for one in the bathroom, but couldn’t find it. However, it must be about the place somewhere. I’ll have another look.’
‘I should very strongly advise you to do so,’ said Dr Priestley. ‘This morning, you were under the impression that the poison had been swallowed. The cut on the dead man’s face had therefore but slight significance for you. Now, however, you know that cut to have been vital. How and when the cut was sustained should be the basis of your future inquiries.’
5
Next morning, upon his arrival at the Yard, Hanslet found the official report of the post-mortem awaiting him. It was a voluminous and highly technical document, but it told him no more than he had already learnt from Oldland.
He put it aside and turned to greet Inspector Waghorn, who entered his room at that moment.
‘Well, Jimmy, and what about our two young friends?’ he asked.
‘I saw them down to this place, Lassingford, yesterday afternoon,’ Jimmy replied. ‘It’s only a village, and, of course, everybody there knows Philip Harleston. He lives in a cottage on Hart’s Farm. Nice little place, wouldn’t mind living there myself. They didn’t know I was behind them all the way, of course. When I had seen them safely installed, I went and had a chat with the local constable. He’ll let us know if they attempt to make any move.’
‘Janet will have had a summons to attend the inquest by now,’ said Hanslet. ‘It’s fixed for this afternoon at half-past two. We shan’t produce any evidence at this stage, and there’s bound to be an adjournment. That will give us time to look round. And, since you’re here, Jimmy, you may as well come along with me and we’ll have another look over that house in Matfield Street.’
On the way Hanslet explained to his subordinate the disconcerting paradox revealed by the post-mortem. ‘You see how it is,’ he said. ‘The experts say that Harleston could not have been poisoned by the tea. They are confident that his death was due to absorbing the poison