CAPING WITH THE CAR.

Press, Volume LXVI, Issue 20103, 5 December 1930, Page 10

CAPING WITH THE CAR.

"'Roadster'' invitee articles and paragraphs of Interest to motorists for kills page, COLOMBO STREET WORK. Congratulations are duo to the City Engineer and his staff, on the rapid and satisfactory manner in which they Jxave relaid the surface of Colombo street south from Carlylo street :o Brougham street. Tho schedule allowed until December 23rd to complete the f irork, but it will bo finished to-day. Two inches of bitumen carpet were laid over 1200 square yards in eight hours, which may be regarded as a first class piece of workmanship. The Christchurch Tramway Board worked in cooperation with the City Council's engineering department in relaying the road. It is a pity, however, that up to the present nothing has been done 10 relay that portion of the road over which there are several railway tracks. This crossing comes under the control of the Railway Department, and consequently neither the City Council nnr the Tramway Board can be blamed for its present state, which is little short of disgraceful, and is the more noticeable since tho roadway on both sidei of it is now in such splendid condition. Motorists would be very pleased to know that tho work was shortly to be taken in hand. AUTOMATIC SIGNALLING SYSTEM. Having been in operation for nearly a fortnight now, the electrically controlled traffic signal system at the corner of Colombo and Cashel streets is beginning to be understood by Christchurch people. Inspectors have been on duty at the intersection daily since the apparatus was put into service, and they havo in*tructed tho public into understanding the signs. A few motorists still show ignorance of the system, but the great majority give no trouble, while a big improvement is also noticeable in the observance given to it by cyclists. Some pedestrians, however, who should know better, stubbornly refuse to be controlled by it. Earlier in the week "Roadster" saw an old lady walking across the intersection. The inspector on duty requested her to go back to the footpath which she had just left, but she refused, although the red light, signifying "Stop" was showing against her. When slio had crossed thi road, the inspector told her very politely that sho should have observed tho signal, whereupon she turned on him ;u*ith fh© remark: ''You have no right to speak to me like that." Tho novelty of tho system is passing, and consequently there are fewer people congregating at the corner to watch it than was the case a woek or so ago. Concerning automatic traffic control, generally, it is noteworthy that the signalling engineer of Syracuse, New York, has reported that 20,000 street intersections in the 'H'nHed States are controlled by ituch means, as a result of which the municipalities of America are being saved approximately £23,000,000 per annum.

TOB CYCLISTS' SAFETY. One of the moat sensible by-laws ever passed by the Christchurch City Council was that -which compels cyclists to have portion of the rear mudguards of their bicycles painted white, so that they might be made conspicuous at night. The idea prcbablv arose from the white stockings sometimes worn by young women, many a motorist having had his attention directed to the proximity of * woman cyclist ahead of his car on a dark night by such moans, and being able to avoid running her machine down. "While a good number of other by-laws have been disregarded in the past, it must be admitted that this one has been approved whole-heartedly both by cyclists and motorists, and there is no doubt that it provides a measure of safety to both. Eecognis-

' ing tho advantage of the by-law, the South Island Motor Union recently wrote to the Minister for Transport (Hon. \V. A. Veitch) suggesting that, instead of the rear red reflectors on cycles, which are unsatisfactory in that they arc frequently attached to machines in positions which are hard to see, and which lend themselves to the danger of being covered by a coat or a skirt, the mudguards should bo painted white as described. A reply has been received from Mr J. W. Hun ter, Commissioner for Transport, to the offect that consideration is being givon to the passing of legislation on the lines suggested. The by-law has been proved to be ao successful in and around Christchurch that it is to bo hoped that tho Government will act as requested, and sc extend the benefits of the system to other parts of the Dominion. MOTOR TAXATION. Motorists who believe themselves badly treated in regard to taxation in the Dominion should be thankful that they do not live in Great Britain. If they did, they would have something real to complain of in this respect. It certainly hurts one to have to pay that visit to the Post Office once a year and pay the taxation demanded by the Government, but, after all, the amount involved (£3 2s 6d in the case of a private ear, including third party insurance and number-plates) is very small compared with what motorists in the Old Country ore called on to find. A leaflet prepared and issued by tho British Motor Agents' Association states that motorists in England are now paying an average tax per vehiclo five times as high as in tho United States. nvernge tnx par vehicle has risen from £l4 in 1920 to £l9 in 1925, and £27 in 1930.. In 1920 the total •amount yielded from motor taxes was £4,370,000; in 1925 it was £16,485,000; in 1930 it was £41,000,000. COST OF PETROL.

Petrol costs considerably less in tho Old Country than it does in Christchurch, even although the price is lower here than in any other part of the Dominion. A reduction of 2d per gallon was made in Britain at the end of September, the reasons for this being given as weaker prices for crudo petroleum

in the United States and lower freight charges. In the Homo counties zone, which covers about 50 miles round London, petrol from the pump is now Is 4id a gallon, instead of Is t>£d. In England and Wales and Southern Scotland it is Is sd, and in outlying districts Is Cd. Tho last increase in price was in March, 1929, when it was put up to Is 7d. Tho last reduction was in October, 1929, when it was brought down to Is GJd. It is interesting to point out that but for tho tax the price of petrol to-day would bo Is o}d. In the Home counties area national benzole mixture is the same as petrol from pumps, and national benzole is Is lOd per gallon. In Christchurch to-day the price of motor-spirit is Is lid for second grade and a penny per gallon more for first grade. British Trade. Some interesting facts emerge from an investigation of the British motor industry at Home and overseas, in view of the present trade depression. The industry has suffered in only a minor degree from tho prevailing trade slump, as the figures of imports and exports for the seven months to July, 1930, as compared with the corresponding period of 1929, indicate. Tho imports of cars, commercial vehicles, and chassis during this period havo totalled 8118 to a value of £1,315,340, as compared with 27,579 (valuo £3,302,767), a decrease of 19,401 (value £1,987,427). Of this decreaso cars have dropped from 9072 to 4445, while tho import of chassis have decreased from 17,803 to 3C41. Whatever additional reasons there may havo been for this it is at least fairly clear that there is an increasing demand in the Homo market for British-mado motor vehicles, which fact is further emphasised by the figures of the July monthly return. In that month this year only 285 cars were imported, of a value of £01,484, as compared with 1181 in the same month last year, of a value of £184,801. In tho samp month chassis dropped from 3085 (value £242,104) in June, 1929, to 302 (valuo £43,378) in th'e snmo month this year. Exports of British cars, commercial vehicles, and chassis also showed a alight decrease, the figures for the seven months of this year being 18,915 (value

£4,330,009), as compared with 24,819 (value £4,930,908), a decrease of 5904 to a value of £(500,299. It was not only in Britain tlmt there was a decrease in the number of motor vehicles manufactured, trade having also been affected in U.S.A. Production of passenger cars in the United States in the first six months of this year fell to 1,899,527, as compared with 2,773,930 during tho corresponding period of 1929. Thero was also a fall in the number of trucks manufactured.

CAUSES OF ROAD CORRUGATIONS.

What aro the causes of corrugations on roads? This is a quostion which has been asked for years, and as yet there does not appear to have been any definite reply to it. Unfortunately, there are many roads in tho province which are affected in this way, and to somo motorists they are known as "Four or Forty" roads, which means that they have to be driven over at either one speed or tho other, it the driver is to avoid having his car being bumped about in an uncomfortable manner. Thero is a very bad stretch o* corrugated road on tho route to Akaroa, near Motukarara, and there are others on tho Main North road away from the paved portions, which aro well known to Canterbury motor ists. It is remarkable that tho distance between the crests on a corrugated road are genorally tho same, no matter what road is examined. Most pcoplo who havo driven over such roads have pondered the question, and all sorts of theories have bee ad vanccd in respect of the question. Some motorists are firmly of the opinion that tho trouble is duo to tho beat of an internal combustion engine, others ascribe it to operations of .steam rollers, others again to tho periodicv of the vibration of a vehicle, and .so on. An Informative Paper. "Hoadster," on making enquiries into tho matter, learned that the ques-

tion was discussed at the annual mooting of the New Zealand Society of Civil Engineers, at Dunedin, in February, 1924, when a paper on the subject was read by Mr G. V. Anderson. The paper stated that if a succession of cars all of the one weight nnd running in the one direction at the same speod wcro driven over a water bound macadam road they would run smoothly until somo inequality in the surface became manifest in the shape of a bump or a hole. The wheel of a car would drop under spring pressure into the hole, and as it passed it would bo forced up again. Going at high speed inertia would carry it t >ast its normal position until the spring sent it back to the road with an impact. Each successive wheel would repeat the process, each wheel would leap out of the hole and land on the same spot till a second hole was formed with a ridge between, after which a third and a fourth hole would be formed. Like a stream, these undulations would chase each other along the road in the direction of the traffic. In the case of a road, however, the traffic was not all in the same direction, and therefore the corrugations became stationary. It would be noticed, continued the paper, that corrugations did not occur on all roads nnd wore not present on grades where the engine accelerated or where brakes were habitually used, but at places where a car ran freely with little engine action. With respect to the objection that heavy lorries with low speeds would not co-operate with cars in producing corrugations, the paper stated that on roads subject to heavy or predominant lorry traffic corrugations did not develop. Potholes might dovelop, but those were due to oscillations in the whole mass of a loaded vehicle. Though somewhat similar, they lacked the characteristic regularity of corrugations. The opinion was expressed by Mr A. J. Paterson that corrugations were caused by the impact of a vehicle and the spring on tho axle. Another engineer thought that corrugations were caused by tho synchronous vibration of the springs. The pressure on tho backs of the corrugations at every vibration tended to form waves, the same as waves formed on the water, with the difference that waves on the solid road, when once formed, were waiting for the next action to take place, which might happen two hours later. The springs on cars were do signod for certain periodical vibrations. If a car travelled at a rate equal to 50 por cent, beyond the synchronous speed, it struck the back of ono corrugation and landed on the middle of the next. Regarding corrugations being found on flat roads and not on hills, he thought that this was due to the fact that on hills the driving wheel tended to move back rather than drive forward the hump of the corrugations Further Data. Some interesting conclusions regarding corrugations have been arrived at by Mr George E. Ladd, Economic Geologist to tho U.S. Bureau of Public Roads. Jle states, inter alia, that corrugations are from 25 to 35 inches apart and average 31 inches. The maximum height from the bottom of the trough to the top of the crest is inches, any greater height indicating

the beginning of pitting or ravelling The corrugations in the iirst method of development are duo to the "kick back" of surface materials arising from the spin of the rear whecla as they descend after bouncing over some obstacle, and in the second method of development to the squeezing of the gravel, , rendered more or less plasty by the presence of clay, and consequently of moisture. The corrugations do not migrate. Except under spscial conditions they are normal to the axis of the road. Cases have occurred wkere they appear to swing on an axis near tho centre of (lie road. Some time ago measurements were taken on corrugations of eleven roAcls in the Hawke's Bay district, where the conditions were suitable for speeding In all cases one chain was measurod off, and tho number of corrugations counted. In all twenty places wene tried. The extreme distances from crest to crest varied from 2G to 3t> inches, the average of the whole bcin* L'Dii inches. It was found that, iA gi neral, the corrugations were more pronounced and more regular when on slight curves. ( orrugation measurements taken in the Manawatu County showed the average width to lie 29 inches. it is noteworthy that the average diameter of the rear wheel (including the pneumatic tyre) of cars also measure "U inches.

NOTES. To utiend the quarterly meeting of the South Island Motor Union in In-vert-argil! to-day the following delegates left Christchurch yesterday:— .Messrs K. \V. Johnston (president of the Union), l'\ \V. I'le-oman, 11. (J----llai'ley, I*. It. llarinan, J. S. Hawkes, and 1,, l'alck. of the reinits to be considered at tin; quarterly meeting of the South Island Motor Union at jnvercurgill today is the following, which has been forwarded by the South Canterbury Automobile Association:—That the Government be approached with a vie"' to standardising tho warning devices at railway level crossings. Another remit from the North Otago .Motor Association is. as follows: — That it be a recommendation to clubs and Associations alliliated to the South Island Motor Union that a uniform charge ho made to non-members f°r tho assistance of patrolmen. It is suggested that the charge bo a.t the rate of say os an hour, and that the charge be remitted if the assisted person join as a member within one month of tho dato of. receiving such assistance.

Other business to be dealt with illrbides tho question of outside hotel sijins, consideration of motor drivers' licenses. a now form of aureernent with tlic Ivovrl Automobile Club (England), and ,-r demonstration of a level crossing signal. A discovery made some time ago by .Mr I'". W. Saxon, a Christchnrch chemist, concerning a new and chciper itieih'id of paving roads by means of a eHd-mix system, has been followed up by that gentleman. who states that in association with Mr R T5. Cotton, civi! engineer. h(> ha= developed tho process, and claims that the quality and strength of tho mix is equal to that ol hot-inix. Ho has laid Uown a snort, experimental stretch of roadway ni Cashmere road, which gives promise of complete success. Tho great advantage ol the mix, he claims, is that a road may bo constructed at any distance from a central plant througliotit the year, as paving operations may be carried out in both cold and wet weather without detriment to tho finished roud. Also, since tho plant is very much simpler than that for hot-mix and is portable, tho laying may bo done at the actual site, and where it is desirable to scarify a road, the material so treated may be coated and relaid as asphaltic concrete. Portion of the main highway between Sumner and Evan's Pass is in need of attention. It shows up badly when compared with tho road between tho Pass and Lyttclton, which is a pleasure to travel over. Mr W. G-. Walkley, of Flawera, has been appointed acting secretary of tho North Island Motor Union. He is to carry on until the annual meeting in August next.

A SONG OF THE HIGHWAY. 'Die dusty road Runs Car across the distant purple hills ; The small car thrills Ti fool the swift accelerator's goad. And leaps to do the bidding of her lord A minor chord Marks tin; first changing of the willing gears. She hoars And gaily singing mounts tho steep ascent, Nor seems as if her purpose can relent. The hedges bend And suddenly seem pointing to the skies: Her singing dies And drops in sullen thirds as if to end. But quickly comes again the gear's gruff sound, And witli a bound She bears us gladly up the final steep To sweep Like swallows gliding from the windy henth. Past woods and hedges to tho vale beneath. —lf. SHOWELL STYLES, in the "Light Car and Cyclecar."

RACE OF 1000 MILES. BIG ITALIAN EVENT. The roost unusual and longest motor race in the world is held annually in Italy over a distance of 1000 miles. The raco is organised by the Automobile Club of l?rescia, and, starting from the town from which the club takes its name, the course traces a rough figure through Bologna, Florence, Rome, Ancona, back through

Bologna, and on through Treviso, Feltre, Vicenza, Verona and finally back to Brescia. The most unusual feature of the race is its course. The roads over which it is run are left open to ordinary traffic while the race is in progress. An appeal is made through the newspapers to the sporting instincts of the people to keep "Way from the course of their own free will. The request is complied with explicitly, anJ ! this year 140 entries, of all sorts, i sizes and makes, competed over the j 1000-mile route that had arbitrarily been chosen aa the course. I