The automatic maid of Philon:
(the first operational robot in history)
This is about a humanoid robot in the form of a maid (in natural size), holding on the right hand a wine jar. When a visitor placed a cup on the palm of her left hand, she would initially pour wine and subsequently mix it with water following the visitor' s desire.
Description of operation: There are two containers in the interior of the maid, filled with water and wine, respectively. Two tubes that start at the bottom of the containers go through the right hand and conclude at the tip of jar. Two air tubes are exposed to the top of the two containers and go through their interior, passing through the stomach. Her left hand is connected through a joint to her shoulder while a spring placed at its center lifts the arm upwards. Another two tubes commence from the same point and go down (going through and blocking the perforated corners of the air tubes). The tubes of the joint dispose two holes/openings at their endings, the hole that connects with the wine container preceding that which connects with the water container. When the cup is placed at the palm of the maid, her left hand goes down and the tubes of the joint go upwards. The opening of one of the tubes is aligned with the air tube of the wine container, air enters the container and wine flows from the tube of the wine jar to the cup. When the cup becomes half full with wine, the hand (due to its weight) goes further down, the opening of the air tube for the wine is blocked and the flow is interrupted. At the same time, the opening of the second tube is aligned with the air tube for the water container and water starts to flow in the cup for diluting the wine. When the cup is entirely full, the hand continues to go further down (due to its weight), the opening of the air tube to the water container is blocked and water flow is interrupted. Moreover, if the cup is removed from the hand at any time, the left hand goes upwards, the tubes of the joint go down, thus blocking the air tubes and creating a void in the containers and the flow of liquids is halted. Thus, the maid fills our cup with pure wine or wine diluted with water at the desired ratio, depending on the time when we remove the cup from her hand.