James’s room was full of interesting things. A real glory-hole, his mother called it. He was a collector and an experimenter, was James, with an enquiring, analytical mind and more than his fair share of curiosity. He had a fish tank, its air pump bubbling away, a glass box containing hawk moth caterpillars, and mice in a cage. On the walls were crustacean charts and life cycle of the frog charts and a map of the heavens. There were several hundred books, shells and dried grasses, a snakeskin and a pair of antlers (both naturally shed) and on the top shelf of the bookcase his bottles of poison. James replaced the wild flower book and, climbing on to a stool, studied these bottles with some satisfaction.

He had prepared their contents himself by boiling leaves, flowers and berries and straining off the resulting liquor. This had mostly turned out to be a dark greenish brown or else a purplish red, which rather disappointed James who had hoped for bright green or saffron yellow, these colours being more readily associated with the sinister or the evil. The bottles were labelled conium maculatum and hyoscyamus niger rather than with their common English names, for James’s mother, when she came in to dust the glory-hole, would know what hemlock and henbane were. Only the one containing his prize solution, that deadly nightshade, was left unlabelled. There would be no concealing, even from those ignorant of Latin, the significance of atropa belladonna.

Not that James had the least intention of putting these poisons of his to use. Nothing could have been further from his mind. Indeed, they stood up there on the high shelf precisely to be out of harm’s way and, even so, whenever a small child visited the house, he took care to keep his bedroom door locked. He had made the poisons from the pure, scientific motive of seeing if it could be done. With caution and in a similar spirit of detachment, he had gone so far as to taste, first a few drops and then half a teaspoonful of the henbane. The result had been to make him very sick and give him painful stomach cramps which necessitated sending for the doctor who diagnosed gastritis. But James had been satisfied. It worked.

In preparing his poisons, he had had to maintain a close secrecy. That is, he made sure his mother was out of the house and Rosamund too. Rosamund would not have been interested, for one plant was much the same as another to her, she shrieked when she saw the hawk moth caterpillars and her pre-eminent wish was to go and live in London. But she was not above tale-bearing. And although neither of his parents would have been cross or have punished him or peremptorily have destroyed his preparations, for they were reasonable, level-headed people, they would certainly have prevailed upon him to throw the bottles away and have lectured him and appealed to his better nature and his common sense. So if he was going to add to his collection with a potion of datura, it might be wise to select Wednesday afternoon when his mother was at the meeting of the Women’s Institute, and then commandeer the kitchen, the oven, a saucepan and a sieve.