Of Machines for Elevating of Waters.
HESE Machines were of four sorts.
Lib. 10. The first was the Tympan, of which there were two sorts; The first elevated a great deal of Water, but not very high, for it only mounted to the Axle-tree of the Tympan, which was a great Wheel made of Planks which made two bottoms divided into eight from the Center to the Circumference, each Separation, having an opening half a Foot wide near the Circumference to draw the Water, which being elevated upon the Axle-tree, ran through the Cavities which were hollowed in each Separation.
The Second Machine, was a Wheel which elevated the Water as high as its Circumference, by the help of several Boxes which were fastned round about, and which poured out the Water into a Reeve as the Wheel, having mounted, began to descend.
Lib. 10.
Chap. 2. The Third Machine was a Chain with Buckets, as the one mounted, the other descended, being drawn by the Axle-tree.
The Fourth Machine was the Vice or Skrew, which is attributed to Archimedes, though Vitruvius makes no mention of the Inventor. This Vice was made of a piece of VVood, long sixteen times its Diameter: about this piece of Wood was put Obliquely a Hoop of Willow Hoop of Willow VVood besmeared with Pitch, and it was Conducted by turning from one end of the piece of the Wood to the other: Upon this Hoop others were put so that they were like the Vaulting of a Stair-Case whose ascent goes turning. This being done, this Vice was fastned and strengthned with Planks, which were pitched within, and covered with Iron Rings and Plates without: At the two ends of the piece of Wood, were Pins, which entring into the Suckets, made the Machine capable of Motion. This Vice or Skrew was placed according to the bent or sloping of the Triangle Rectangle of Pythagoras. This Machine elevated easily a great quantity of Water, but it could not carry it high.
The Fifth Machine, was the Pump Lib. 10.
Chap. 2. of Ctesibius; it was composed of two Bodies of Pumps, in which the Suckets having drawn the VVater when they were pulled up, they both pressed it violently into a Pipe which was fastned at the bottom of the Body of the Pump when they went down. For the VVater by the Impulsion of the Sucket, was forced to enter into these Pipes, because it could not go out by the Openings by which it entred, because of the Suckets which stopped them, these two Pipes were joyned together in a Tambour, which had likewise its Suckets, which hindred the VVater from descending into the Bodies of the Pumps, after it had been pressed into the Tambour, or Vase, which had another Pipe, through which the VVater was forced as high as they pleased, by Impulsion of the Suckets.
Lib. 10.
Chap. 10. All these Machines were either moved by Strength of Men, or by VVater-Mills, according to the convenience of the place.