THE ROADWORTHY CAR

NZ Truth, Issue 1149, 8 December 1927, Page 18

THE ROADWORTHY CAR

Some of the Things that Count

Every motorist has a fairly clear idea as to the type of car which he would apply the term * ' roadworthy' ' — and the type which this term would obviously be very inappropriate !

BUT to proceed to make a list of the automobile virtues which go to I i make up the quality of roadworthiness] is much more difficult, some being j found m the constructional features, j while others have more to do with the j way m which the car handles and its ( general layout. In short, the truly roadworthy car must be not only of sound and reliable construction, but also so designed as to be entirely trustworthy under all I sorts of difficult or treacherous road conditions. The really roadworthy car must be easy to handle, must corner unfalteringly, steer to a hair'sbreadth and hold the road without swaying or bouncing. Consequently, it is easy to deduce that it should be of low build. It has, indeed, been a marked trend for some time to build cars with the chassis frame nearer and nearer to the ground, this having been rendered necessary by the consistent increase m, car speeds. The lower the frame level the nearer is the weight brought to the I road and the lower does the centre of gravity become, this centre being the i point at which one can imagine the whole weight of the car to be concentrated. If this conception be grasped, it will be clear that a car can be tilted sideways with safety until an angle is reached at which the centre of gravity comes exactly over the point at which the tyres meet the road, any further tilting leading to instability and overturning. Clearly, the lower the centre of gravity and the wider the track the bigger will the permissible angle of tilt become. Comparing a modern, low-built car with one of the type common a few years ago, it will be found that the height of the centre of gravity has decreased by at least 25 per cent., with the result that the angle of tilt has increased from about 45 degrees to 65 degrees. As no one makes a habit of cornering on two wheels only, it might be questioned whether this matter nf the height of the centre of gravity is really of such great importance.

It, therefore, seems necessary to explain that the outward centrifugal force, which is set up when a car follows a curved path, acts through the centre of gravity, and it will be clear that the higher this centre of gravity is placed the bigger is the overturning effect exerted by this force. Furthermore, the tendency to rolling and side-sway when cornering — each of which gives the occupants of the car a sense of insecurity — becomes the more marked the higher the centre of gravity. The suspension system is another factor of great importance. The enthusiast for roadworthiness will prefer one which holds the car down at the expense of a little additional vibration rather than one which gives extreme comfort at 25 m.p.h., but allows the car to bounce dangerously at double this speed. There is no real reason, however, why an all round improvement m suspension systems should not take place.

"What a blessing this smoking is! Perhaps the greatest we owe to the discovery of America." So wrote the late Sir Arthur Helps, and millions of smokers the world over have doubtless endorsed his words. But great as is our indebtedness to America for giving us the priceless boon of tobacco, the ract remains that practically all the American brands m use to-day contain an excess of nicotine. And that :s bad, as any doctor will tell you. It is no less true that the purest tobaccos of all — i.e., those comparatively free from nicotine are our own NeAv Zealand varieties. They are bo pure, m fact, that they may be indulged m with the utmost impunity. The leaf is toasted m the process of manufacture. Hence their delicious flavor and delightful fragrance. They come m several strengths, and are thus adapted to all tastes. You can get them at any tobacconist's. Ask for "Riverhead Gold" mild, "Navy Cut" (Bulldog) medium, or "Cut Phig No. 10" (Bull's head) full strength.*