In the novel Death in the Clouds, Mr Henry Winterspoon is a chief government analyst and an expert on poisons. He gives evidence at the inquest into the death of Madame Giselle. According to Winterspoon, he had been asked to examine the thorn which had been used to kill the lady. He found that it had originally be dipped in curare but there was only a very small trace of it. More recently it had been dipped into the venom of Dispholidus typus, a South African snake commonly known as the Boomslang or Tree snake.
Winterspoon is described as a large, dreamy-looking man with a benignant expression. He looked "kindly but stupid" but he surprised everyone at the inquest by his expertise.