Michael had outstanding talents both as an experimental physicist and as a numerical modeller of physical phenomena. While at Harwell in 1959, along with Cranshaw, he measured the absolute difference between the charges of the proton and the electron, showing it to be less than 10-20 times the electronic charge: this remains one of the best measurements of this quantity. At that time, some years before the discovery of the microwave background radiation, it was thought that a charge difference between these two particles might contribute to the expansion of the Universe. However, it was unquestionably his quite remarkable ability to combine unusually penetrating physical insight with extraordinary powers of calculation that led to the works for which he will be best remembered. At a young age he could add and subtract logarithms in his head while in the days before computers or electronic calculators were available, his prowess on the slide rule was legendary. He had engraved the logarithms of the fundamental constants on the back of his 5-inch slide rule and consequently could estimate the magnitude of effects with extraordinary speed. Using the calculating power of modern computers, he developed a world-renowned series of Monte Carlo calculations which embraced algorithms of great ingenuity and beauty. With these he was able to achieve results more elegantly and more rapidly than any of his competitors or imitators. Indeed, his record on any computing device showed him to be vastly superior to any one else in his ability to attain results of importance with high efficiency – and he always had a good idea of the answer before he ran the program.