CHAPTER I.

OF MACHINES AND ENGINES.

A machine is a combination of materials capable ofmoving great weights. It derives its power from thatcircular application of motion which the Greeks callkvkXlkt] klv7}(tl’5. The first species is for scaling (scan soria),which the Greeks call aKpofiariKos. The second, whereinthe wind is the moving power, is, by the Greeks, called7rvevfxariKb<s. The third sort of machine is for draught, andthey call it (Sdvavo-os . The scaling machine is constructedfor the purpose of ascending, without danger, to viewworks of considerable altitude, and is formed of longpieces of timber connected together by transverse pieces.The pneumatic machine is for the purpose of imitatingthe sounds of stringed and wind instruments, by meansof a rush of air organically introduced. Machines ofdraught are constructed for the purpose of removing orraising great weights. The scaling machine is one moreof boldness than art, being a combination of longitudinaltimbers connected together hy cross pieces, the splicingswell lashed together, and the whole supported by shoresor props. But the machine which, by the action of wind,produces very pleasing effects, requires great ingenuityin its construction. The machines for draught performmuch greater and more important operations, in theirapplication to different purposes, and, when skilfullymanaged, are of great utility. Of these some act me-chanically, others organically. The difference betweenmachines and organs is this, that the former are composedof many subordinate parts, or propelled by a great power,as balistse for instance, and wine-presses; whereas, thelatter, by an ingenious application of the moving power,can be set in motion by a single person, as in turning theaxis of the scorpion or anisocycli. Thus organs, as wellas machines, are extremely useful and necessary, inas-