Вечные двигатели

For many centuries, inventors have tried to create an eternal engine. The first 'official' attempt was made as early as the 8th century AD, and some are still trying today to come up with a mechanism that could always work without external intervention. One can even confidently assert that humans will forever be inventing eternal engines, such is our nature! In his book, the famous physicist and science popularizer Yakov Isidorovich Perelman will tell about the types of perpetual machines that have already been attempted in the past and why these attempts were unsuccessful.