Inventions that Changed the Course of Humanity!!
In 1937, in the United States of America, began the sale of heaters that produced hot air with the aid of electricity. Soon the system was added to a circuit attached to a container of water. This produced heat to the water. It was made with the use of gas, firewood, electricity, carbon etc... It became of great use in those countries where the temperature drops to a large extent. The heater has gone through many designs since its creation.