The Press., 1904-07-13
THE MODERN WHEEL
IT'S DEVELOPMENT FROM THE RUDE LOGROLLER OF AGES AGO.

| | ILOGROLLER OF AGES AGO.
 The Solid Circular Slab of Wood and I the Nail Studded, Perforated Affair
 That Led Up to SpOlxes, Tires and
 Ball Bearings.
 All the world is upon wheels nOwa-
 days, and 1t is extremely difficult to re- alixe that one time there were no such
 aids to motion. How long ago it must
 have been there is no possibility of de
 termining. The origin of the wheel is
 quite lost in the obscurity of the past.
 But though we cannot trace the wheel
 to its actual inception, there is to be
 found in the rude sculptures and pic
 lures of the past enough in the way of
 hind and suggestion to show how 1t | probably originated. It is reasonable
 to suppose that the sledge would have
 preceded the wheeled vehicle. To drag
 along thing by main force is what
 many of the lower animals are accus-
 toned to do, and, of course, human be- ings must have done 1t from the infan-
 cy 3f the race.
 The first step in the evolution of ex-
 press trains and motor cars would nat
 urally have been an attempt to facili-
 tate the movement of whatever was
 being hauled along by smoothing the
 under surface where practicable and
 leveling the road. Where the under surface of the burden could not be smoothed the obvious alternative would
 have been to get it on the top of some
 thing which did permit of the smooth
 ing-something in the form of a sledge, that is to say. It is certain that this primitive vehicle was known to the early Egyptians. ....# In Wilkinson's Ancient Egypt" there is the reproduction of picture found in grotto behind E'Dayr, Christian village between Autinoe and El Der l sheh, representing the removal of a colossal statue. It is mounted on a sledge with runners underneath, and 1t is being hauled along by 172 men pulling at ropes, while in front of the | sledge a man is pouring down some sort of fluid, probably grease says the learned author, and he adds that, al- | though it is not shown in the picture, the roadway would most likely be laid with blanks.
 That, in all probability, is the rudi- mentary idea of a modern railway truck travelling over an iron rail. There is the loaded vehicle, and there is the specially prepared road. The gradual l evolution of the modern conveyance and its facility of motion would be only question of time and of mother wit slowly effecting small improve ments. That picture itself is suppos- ed to date nearly 2,OOO years before the Christian era, and how much far ther back the work itself would go it is impossible to say.
 It is easy to conceive that pure ac- cident may have suggested rollers un- derneath the sledge as a means of rendering its movements easier. But whether accident or invention may have done it the use of rollers in this connection was clearly the next move. This is shown in the famous Assyrian sculpture of the moving of the winged bull There we find the sledge and two rollers beneath 1t, and it is dim- cult to suppose that the wheeled ve- hicle was known at that time, or it surely would have been employed in- stead of the more primitive sledge. The sledge and the rollers having been arrived at, we have no positive infor- nation as to how the next stage was reached, but it is not difficult to con- ceive what might quite feasibly have happened. A simple modification of the roller might very well have af fOrded the germ of the modern wheel and axle If we imagine the two rollers somewhat reduced in size in the middle, so as to drop the sledge down little and prevent its running off the roller ends, we get the incipt- ent wheel and axle at once, and some sort of plug in the bottom of the sledge before and behind each axle would prevent its running from under the vehicle, and there would be the 1ncipient wheeled cart. In Portugal there is said to be in use a farm cart in which just such plugs as these are actually found beneath the body of the vehicle, which may thus be lifted off its wheels. What would probably be the next stage of the process of devel- opment can be traced in the available records of the past. Instead of roller being merely reduced in the middle, with its introduced ends form ing solid wheels, we find a very early pictorial representation of vehicle in which broad slices have been cut off from the round bole of a tree and connected under the sledge by bar through their centers
 There are the wheels, for the first time in pictorial record, separate from the axle. For the first time the actual wheel appears, but the square end of the axle plunged into It's center shows that wheel and axle went round to- gether, and the next stage, no doubt, would be to fix the axle and let the wheels run loosely round its reduced ends, the wheels being kept in their places by something in the nature of linchpins. That would be a distinct stage in the line of progress, though 1t is curious to observe that in our rail- way carriages and motor vans we have got back to what no doubt was the earlier form, the wheel and axle re- volving together in bearings.
 The earliest wheel of which we have any representation is just solid circu- lar log of wood, such as might be sliced off the end of tree trunk, and that, there can be no doubt, must have been the earliest form of the thing. It is again curious to notice that in some of our very finest railway trains we have got back to that most primitive of all forms, the solid wheel. But these circular slabs of wood, as they got dry, would be very likely to crack and split under rough usage, and both i'm Greece and Portugal we find in a. tual use farm vehicles with wheels made up of several pieces of wood nailed together. This would be a dura- ble form of the same thing-the solid wooden wheel-and in Buffers Win ter In the Azores' there is an illustra- tion that may be considered to give the