In the early sunny morning, the postman delivered to the Royal Society – the English Academy of Sciences, a letter from an extremely angry American scientist: "Some Kelvin began to claim a galvanometer, which, as the whole world knows, was invented by the respected Sir William Thomson!" The American was outraged by the impostor's audacity, the indifference of the Royal Society and wondered why Professor Thomson himself was silent. William Thomson and Lord Kelvin are two names inextricably linked in the history of science.