To humans, cold has a distinctly positive quality. 'Frostbite', 'a nip in the air', 'biting cold', all express the concept of cold as an entity which attacks the body, numbing and damaging it in the process. Probably the richness of descriptive English in this area stems from the early experiences of a group of essentially tropical apes, making their living on a cold and windswept island group half- way between the Equator and the Arctic. During a scientific education we soon learn that there is no such thing as cold, only an absence of heat. Cold does not invade us; heat simply deserts....