PROFESSOR ROBERT HARKNESS was my PhD supervisor between 1973 and 1977. He and his wife remained my close friends for the rest of their lives. Robert was interested in everything. His was not a fleeting interest, but a deep, enquiring passion. He was fascinated by the contents of hardware shops, especially when making his annual overland trips between the UK and the North of Greece.

During his explorations of these shops, he noticed that the designs of traps for rodents varied from place to place. Many of them were constructed so that the rat or other pest was not killed when caught in the trap. Over the years Robert collected a wide variety of differently designed traps.

Today (the 8th of December 2023) when wandering through one of the many bazaars in Surat (Gujarat), we spotted a metal worker’s shop. On a table outside it, there were a pile of rat traps for sale. They looked like little sheds or garages. At one end of each of them, there was a sliding door. Bait is placed in the far end of the trap. When a creature touches this, the trap door drops down and imprisons it. I do not know what the owner of such a device does with the victim enclosed within it. I suspect that the animal might be killed by drowning.

The owner of the shop said that most of the traps on display were made elsewhere, but he showed us one he had made. As we examined the traps and other ironmongery on offer, I thought how much Robert would have enjoyed visiting this shop.