Famous for his Perpetuum Mobile, Drebbel built and navigated a submarine. Built an incubator for eggs and a portable stove / oven with an optimal use of fuel, able to keep the heat on a constant temperature by means of a regulator / thermostat. Designed a solar energy system for London (perpetual fire), demonstrated air-conditioning, let it rain, made lightning and thunder ‘on command’, developed fountains, fresh water supply for the city of Middelburg. Involved in the draining of the moors around Cambridge (the Fens). Developed predecessors of the barometer and thermometer, the "Drebbeliaensch instrument", harpsichords that play on solar energy.