Page:The Kinematics of Machinery.djvu/231

 ANCIENT WHEELS. 209

Egyptian sculptures and paintings, and those also of the ancient Assyrians and Greeks, frequently show us some details of the construction of these primitive wheeled vehicles. The Assyrians and Egyptians used for the most part wheels with six spokes, those of larger diameter and more clumsy construction having sometimes eight, and even twelve. The Greeks preferred wheels with four spokes only. The wheels constructed with the smaller number of spokes are the more perfectly made ones ; originally of wood, they appear in time to have been made of w r ood and metal together, and at last entirely of metal (bronze). 28 Simple disc-shaped and rudely-constructed wheels are indicated by these pictorial records as used by the less civilised nations of Asia Minor. In India to- day also we find rough disc-wheels, besides many with a large number of spokes ; these are used with axles both of iron and of wood. In the Plaustrum, the older form of the ancient Eoman freight waggon, disc- wheels were also used with the notable peculi- arity that the two wheels had square holes through which the wooden axle was placed, the latter having cylindrical journals with bearings in the waggon frame.* Waggons of just such a form are used even now in Portugal, 29 and in Formosa also the aborigines use the same construction. 30

The miniature bronze vehicles which have been found in burial mounds on the North German plain, in Schonen, &c. (and of which the Mainz Germano-romance Museum, among others, possesses some excellent copies) can scarcely belong to a higher antiquity than the ancient vehicles just described, if indeed they be not younger. They are generally supposed to have had a religious signification,-)- and are considered as parallel to the "laver "-carriages of Solomon's Temple ; but there are not wanting important authorities who consider them to have had a quite different nature. It is note- worthy that their wheels have mostly four spokes, like those of the majority of the Grecian vehicles.

Wheeled vehicles were known, however, before the times in which those we have described take their origin. The oldest Indian literature mentions them repeatedly. The following are some of the references to them in the Eiksanhita :

secured in this way.
 * The wheels of " Puffing Billy" (1813), which is now in the Patent Museum, are

t Lisch, Ueber die ehernen Wagwibecken der Bronzezeit. Schwerin 1860.

K P