‘How could the boy’s death have been induced?’ said Prothero. ‘It is possible, I suppose, to arrange certain conditions which might bring on an attack of asthma, but it is most unlikely to result in death. If a patient were chronically ill anyway, I suppose it is not impossible to hasten his departure in such a way, but I have never heard of it. And Guy was quite a fit young man. Besides, this all happened in a public hotel. There were no irregular conditions. As for the horse-ride and the heavy meal, they were in no way unusual for Guy, as his headmasters, whom you appear to have been in touch with, will verify.’
‘More tea?’ said Cribb. ‘I will, I think. What you must remember, Doctor, is that I’m a layman, knowing very little about asthma and its causes.’
‘None of us knows very much.’
‘After three days with the medical books and several consultations in Harley Street,’ said Cribb, ‘I came to that conclusion myself-and I was no further on with my theory. I had to look for something else. The devil of it was that everything was settled to everyone’s satisfaction except mine. I’d thought it possible at one time that poison had been introduced, but the post mortem disposed of that explanation. There wasn’t even a mark on the body to suggest foul play. So I decided to read through all my notes and statements again, hoping something would emerge. Two things did. The first was a remark your son himself made when the three of us were taking lunch at Mutton’s, after my regrettable confusion over the bath-towel in Brill’s Baths. He made a sort of outburst, you remember, accusing you of treating him no better than his half-brother, young Jason.’
‘Certainly I remember. He was being deliberately provocative. I would not place too much reliance on anything he said if I were you, Sergeant.’
‘One of his complaints was about a bruise on his arm from an injection. The size of half a crown, I think he said. You don’t deny giving him one, Doctor?’
Prothero shook his head. ‘I’ve no reason to deny it. I injected a small quantity of atropine to relieve his asthma symptoms. It is a recognised way of preventing constriction of the bronchioles by inhibiting the action of the nervous system. Used by a physician, it is perfectly safe.’
‘So I understand, sir,’ said Cribb. ‘It’s a pity you had none with you on the day the boy died. An injection then might have saved him. But, of course, you weren’t to know. Tell me, was it on the Sunday before we met at Brill’s that you gave Guy his injection? That’s what I’ve got in my notes.’
‘Sunday? Yes, it would have been.’
‘That’s what the boy said. I can understand that he must have been in somewhat of a state that morning, with Bridget lying dead under the promenade, and your wife and second son being sent off double-quick to Dorking. I don’t believe Mrs. Prothero knew what had happened, but I’m quite sure you did. A very anxious time for Guy, and most considerate of you to give him an injection, even if he was ungrateful later in the week when I met him. I suppose you must have been in quite a wax yourself on that Sunday morning, knowing what the boy had done and wondering what to do about it. Not at all surprising that the injection should have left a bruise. Was your hand shaking, Doctor?’
‘I have no recollection,’ said Prothero.
‘I didn’t expect you to have, sir, particularly as there was no sign of the mark fourteen days after, when the boy’s body was examined. These things heal quickly, especially in the young. You don’t mind if I have the last doughnut? It’s more than I could do to leave it.’
‘What was the other thing that emerged from the statements?’
Cribb chewed heartily and used the uneaten portion of the doughnut to emphasise his points. ‘Ah, yes. The length of your holiday. Your wife said you were there for three weeks, but you stayed for four.’
‘There were things to attend to, consequent upon the death of Bridget.’
Cribb smiled. ‘I can well imagine, Doctor. But once the severed hand was discovered in the aquarium, on the Monday, there wasn’t much prospect of disposing of the body, which was already dismembered. Just time, perhaps, to bury the head somewhere else in hope of preventing identification. But by the middle of the week the rest of the parcels were found. If you’d left the town at once, suspicions might have been aroused, I agree, but you could have left quite openly at the end of the week, when your holiday was due to finish. Instead, you extended it by a week.’
‘It was only right that I should see things through, as Bridget’s employer.’
Cribb dismissed this with a quick shake of the head. ‘It was obvious to anyone that the matter had passed out of your control. Bridget was the subject of a murder inquiry, and an inquest was certain to be arranged. You could have been waiting for months if that was why you were still in Brighton. No, I think your motive was another one. You stayed there because of Guy, not Bridget. You knew he was going to die on the second Sunday after the murder. It was quite contrary to your plans that he should die at home in Dorking. There would have been no end of questions and suspicions. Instead, he died on the way home, in a public hotel, as you so rightly said.’
‘I am supposed to have known all this? How do you imagine I possessed such clairvoyance, Sergeant?’
Cribb wiped his fingers with the table-napkin. ‘No clairvoyance to it, sir. Timing, that’s all. Fourteen days from the injection, Sunday to Sunday.’
‘This is too preposterous!’ said Prothero. ‘Am I seriously supposed to have killed my own son with an injection of atropine that took effect two weeks after it was given, caused a violent death with all the symptoms of asthma and left no trace in the body? You had better spend some more time with the medical books, Sergeant. You have a lot to learn.’
‘I appreciate that, Doctor. So when I formed my suspicions, I went back to the library to read all that I could find on the subject of injections-and the deuce of a lot there is. What caught my interest in particular were the inoculation experiments being carried out by Dr. Pasteur and others. In fact, it seems that half the doctors in Europe are busy pumping germs into dogs and guinea-pigs and publishing their results.’
Dr. Prothero sighed in a long-suffering way. ‘Perhaps what you fail to appreciate, Sergeant, is that such experiments are intended to give protection against disease, in the same way as vaccination. Now that the organism responsible for typhoid fever has been discovered in Germany, for example, it is possible that we shall soon be able to inoculate the populace and so limit the spread of the disease. Experiments are already being conducted to that end.’
‘So I read, sir. But it isn’t quite so straightforward, is it? There are problems. While I was reading of these experiments I several times came across something the doctors describe as “acute respiratory shock”, which seemed to have nothing at all to do with the disease under investigation. An animal that had been injected would suddenly appear to suffer extreme difficulty in breathing, followed by convulsions which frequently ended in death. Now this interested me a lot, so I went back to Harley Street to see if someone could explain a little more about it in simple terms comprehensible to a member of the Force, such as myself.’
‘It is a phenomenon well known among doctors,’ said Prothero.