This is an interesting experiment the amateur can do if he can get hold of temperature sensors that can be placed in the brood nest and read from outside the hive. On second thoughts a gardener's maximim/ minimum thermometer might suffice. My first guess at the result of the experiment is that variant B of Newton's third law (each action is opposed by an equal and opposite reaction, especially when playing with Bs) will occur: the efforts of the beekeeper to raise the temperature of the broodnest to what HE THINKS it should be will be exactly matched by the efforts of the bees to maintain the temperature at what THEY KNOW it should be. Chris Slade