The Fifth _Machine_, was the Pump 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. [Sidenote: _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. ART. V. _Of Water-Mills for Grinding of Corn._ [Sidenote: _Lib. 10. Chap. 10._] _Water-Mills_ were moved by the help of a great VVheel which had many VVings, which were forced by the Current. The Axle-tree of this great VVheel, traversed another VVheel which had Cogs, which made the _Lanterne_ or _Trundle-head_ go, which was placed Horizontally, which was traversed by a Beam of Iron, which entred through above, into an Iron in form of a VVedge, which helped to fasten the Beam in the Mill-stone, above which was the Mill-Hopper, in form of a Funnel. ART. VI. _Of other Hydraulick Machines._ There were many other _Machines_ which moved by the help of the VVater, as _Hour-Glasses_, _Organs_, _Machines_ for Measuring the VVays, and knowing the swiftness or slowness of Sailing. The _Hour-Glasses_ marked the Hours by the help of VVater, which passing slowly, a little hole made at the bottom of a Vessel, and falling into another, in elevating it self insensibly in the Vessel which it filled, raised a piece of Cork, which hanging at one of the ends of a Chain wrapped about an Axle-tree, and which had at the other end a little Bag full of Sand, and a little lighter than the Cork: for this Chain turning, the Axle-tree likewise turned a Pin or Hand, which marked the Hours upon a Dial. [Sidenote: _Lib. 10. Chap. 12._] The _Organs_ played by help of two Suckets, which were pulled up or let down in the Bodies of the Pump. The Suckets pushed the Air with violence into a Funnel reversed in a Copper Coffer half full of VVater, and pressed the Water, and constrained it to ascend round about within the Coffer, which made that its weight in making it re-enter into the Funnel, pushed the Air into the Pipes, and made them Play, producing the same Effects that the Bellows did. [Sidenote: _Lib. 10. Chap. 14._]