The first Watt engines were atmospheric pressure engines, like the Newcomen engine but with the condensation taking place separate from the cylinder. Driving the engines using both low pressure steam and a partial vacuum raised the possibility of reciprocating engine development. An arrangement of valves could alternately admit low pressure steam to the cylinder and then connect with the condenser. Consequently, the direction of the power stroke might be reversed, making it easier to obtain rotary motion. Additional benefits of the double acting engine were increased efficiency, higher speed (greater power) and more regular motion.