MOTORDOM

Southland Times, Issue 20014, 30 October 1926, Page 16

MOTORDOM

BENEFIT TO MOTORISTS.

AUTOMOBILE ASSOCIATIONS. The benefit and powers that automobile associations brought to the individual motorists was the point stressed by Mr R. E. Champtaloup, of Auckland, at the outset of an address to Taranaki motorists. “How many motorists really know what the automibile association does for them?” he asked. “Every member,” he added, “should go armed with that knowledge, but it is a surprisingly small number that really realise the work that is accomplished by associations.” In the first place he pointed out what had been done in recommending legislation and, secondly, the help that was given authorities to carry out the laws. Motorists were once regarded, he said, as pests, and associations as selfish organisations. That was in the days when cars were preceded by a red flag. It was a great tvent in those doys if people, after going out five or six miles, returned home in the same car, and, as motor cars became more popular, more restrictions were brought in that would have driven them off the road had not motorists combined for their own good. It was from those small beginnings that the powerful associations of to-day had ' sprung. The roading policy alone justified . their existence. Taranaki had certainly ! given a lead and was to be congratulated ; upon its roads, but the start of the good roads campaign throughout New Zealand • began with Mr George Henning, who was responsible for the formation of the Good Roads Association, which kept that name because of the feeling towards automobile associations. After a long struggle it finally was carried through in 1918 by Messrs George Hutchinson, M. H. Wynyard, and Henning, who eventually obtained the support of other organisations which sprung up throughout the country. At first it was mooted that the Main Highways Board should have entire control of main roads, but counties objected, and eventually the present highways system was put through. It was the automobile associations that had to be thanked for the better class of road in the Dominion to-day and the fact that the main road to Auckland through Te Kuiti was completely metalled, which means hundreds of pounds to this town. From this Mr Champtaloup dealt with taxation and the early suggestion of taxing upon horse-power. . This had been objected to, particularly in the South, with the result that the tax was fixed at £2 a car, or £8 less than had been suggested in some quarters for a 20 h.p. car. Most owners drove a car of about that power, so that every motorist had really saved £8 a year through the activities of automobile associations.

Those were some examples of what unity could achieve and now, when associations went with united voice to the Government they did receive some attention. To those motorists who had to be shown that for their £1 Is fee they wpuid get £2 2s back, it was necessary only to mention the hotel scheme, the concessions from which would return more than the extra guinea to members during one tour alone. They had also been successfid this year in having the privilege extended from the member alone to a member and family or a car load, the hotel lists being marked accordingly. Illustrating what an association could do for its members, Mr Champtaolup spoke of the Auckland association, which had erected 2500 signs and had coveted 24,000 to 25,000 miles of road for information to give to motorists, and had agents over the whole district, supplying data for the use of motorists in general. A strong association could only be built up by extensive cooperation of members. The Auckland association had 1000 members eighteen months ago. By next Christmas they hoped to have 5000. He urged members of associations to do something for the privileges which they enjoyed. A member should carry an enrolment card with him, and none did his puty unless he enrolled at least one member a month. It should be one a day. CLOSED CARS. The closed car’s increase in favour is evidenced by the statistics published in the United States. Even in Auckland you can see more closed cars on the roads each month. Owners of the regular touring models are apt to classify all closed in cars as hot and stuffy in the summer. Those who have bought modern enclosed models are firmly of the opinion that they are the better type, both for winter and summer. With the disappearing glass windows and tilting front screen, a draught as strong as a hard sea breeze or as light as a zephyr can be created by judicious arrangement of the windows. One fact is convincing, and that is owners of enclosed cars will not voluntarily go back to the older type, preferring them both for city work or touring. Almost every motor firm now markets a number of enclosed models, the variety from the Ford coupe to the Rolls-Royce landaulette ering a wide choice. The following figures show the growth of open and enclosed car production in America for the past seven years—

NEW INVENTION. A great deal has been written lately about the automobile of the future, about its motor, its body, its springs, its tyres, and its fittings, but little has been made public about what has been done with the obviously crude part of the presentday motor car—the gear shift. A device which may prove an answer to this question was given its first public showing in Boston recently, when G. L. Sexton introduced the vacuum gear shift to the few interested onlookers and started on a drive from Boston to Atlantic City, NJ., at the wheels of a machine equipped with the new idea.

The usual lever was absent from the car. Instead a small aluminium quadrant was affixed on the steering column, just below the wheel, and around this quadrant moved a little lever at the pressure of a finger, exactly like the throttle lever on an automobile about 1910. It is noi the first time some device, mechanical or electrical, has been offered to take hold of the gear box and put the little cogwheels where they were wanted. George Const ant in esco, has developed what he calls a torque converter, taking the place of the gear box, with an infinite range of speed. But the vacuum device appears to be the most workable mechanism yet tried out in America.

The new device utilises the suction from the motor intake manifold to “build up” a vacuum in two 34in cylinders attached to the top of the gear box in place of the shifting lever. When the driver gets the

little lever on the quadrant at its position < for “first speed” nothing happens, but the air valves are set ready so that the instant the driver presses down the clutch pedal the change is made. The makers of the apparatus claim there , is no possibility of stripping gears because i the moving of the gear indicator while the car is runping or standing has no effect until the clutch is released. Then the meshing of the new gear is synchronised to ' a fraction of t second as the clutch takes : hold again. In tests the gear has been i changed from <f high” to “reverse” at a driving speed of more than 30 miles an hour, Mr, Sexton said, to act as an emergency brake, with the result that a rear axle was twisted off but not a gear chipped. < The mechanism is the invention of Alvin ' Craig, of Newhaven, Conn. It has undergone four years of perfecting and adaptation to various types of cars, and a company is now preparing to put it into factory pro- ( duction as an attachment for cars now in use. Negotiations are being made with < three or four manufacturers, one of whom ] may adopt it as standard equipment. The first model of the device occupied . nearly four inches of space above the gear- , box. Few cars have this much room under . the footboards. By redesigning it has been f reduced to 5-8 of an inch in thickness, and | at that size is adaptable to every make , of automobile. Tests have been made on ( 600 cars, altogether, representing 26 makes. . j OVERHEATING ENGINE. s I DAMAGE LIKELY TO RESULT. J MAY BE PERMANENT. ‘ . J Damage is likely to result unnoticed < if the engine is allowed to remain in an < over-heated condition for any length of < time. Over-heating affects the cylinders, I the piston, the bearings, and all internal 1 parts of the engine, and is likely to cause permanent damage to some of those parts, ; Running with spark retarded for a long period will cause over-heating; carbonisation of the engine, reduced fan draft, and interference with water flow through the system are a few other causes. When over-heating occurs on the road it is best to stop and investigate, unless the car is within half a mile of water supply. Here an examination and test can determine the exact cause, for without knowing the cause, and correcting it, the filling up of the system with cold water offers temporary relief only. In an emergency the wise thing to do would be . to overfeed the engine with oil. It . will give off volumes of smoke through the exhaust, but- the additional oil offers a protection to the cylinders and pistons. If there is no means of feeding oil, if there is no water supply, and if the driver cannot find the cause and remedy the trouble, nothing remains but to stay on the road until something can be done. Rarely, however, is there not a water supply of some sort within half a mile.The water in the jackets must absorb a certain amount of heat, pass it to the radiator through the tubes or cells, where the heat is transferred to the radiator metal, and then to the air, and after that the water must return ready to absorb a sufficient amount of heat to keep the cylinder wall temperature nearly constant. Certain actions so heat the cylinder wall (hence the water in the jackets) that the radiator and air draft are unable to absorb the excess heat, which means that each time the water makes the circuit it is slightly hotter than it was before. This occurs when running for a long period with retarded spark. With more heat being added each time it makes the circuit of the cooling system, it is not long before the water temperature reaches that of boiling. CORRECTING LEAKS. Anything tending to prevent or retard the flow of water through the system will naturally allow more heat to be absorbed by the water, and thus quickly raise its temperature from around 130 degrees to 212 or higher. If the steam would quickly condense, and in some way get into the radiator for cooling, it would not matter, but we must have outlets through which j the steam passes, and in this way the water is lost. Any serious reduction in the volume of water in the system allows what water is remaining to become too hot, hence it is important that the system always be filled. The rule is—fill the radiator every day. Water leaks can, in a short time, reduce the amount of water and cause over-heat-ing. Leaks may occur in the radiator, in the connections between radiator and en- 1 gine, in the water jackets or joints, such I as detachable head when that incorporates j part of the jackets, or in the pump if one is used. Radiator leaks may be quickly stopped . on the road by the use of cements of various sorts, but if the leak is caused by a large rupture, the cement should not be i relied upon for making a permanent repair. Soldering is better. It is easier to find water leaks “when ' the engine is not running, because when I it is operating drops of water soon are blown away as a spray by the fan draft. Also, when the water is in circulation there | is less chance of it working out through i a small opening. In a pump-cooled engine the pump packing nuts may permit of leakage because of poor packing. In the absence of the regular form of pump packing, ordinary rope of small diameter, waste, or similar stuffing may be used. It is not necessary to tighten the packing nut by applying a great deal of effort to the wrench. Often the hands alone draw it tight enough. COLOURED LIGHTS. ELIMINATION OF GLARE. AMERICAN INVENTION. Although experts all the world over have decided that the dangers due to dimming of headlights are far greater than those arising from the glare when the lights are full on, this does not mean that they are satisfied with the design of headlights as made at present. Experiments are continually taking place, and it is rarely that congress of automobile engineers meets • without one or more papers on this subject being discussed. Most of these discussions centre round the better design of bulbs and , reflectors or more efficient focussing arI rangements, and much work has been done ■ in narrowing down the glare beam so that . it is not unpleasant to oncoming drivers. ; A member of the American Bureau of > Standards has put forward a novel scheme : to eliminate unpleasant and blinding glare, i In his system Mr. Chambers makes use of [ what he calls complementary colours, employing lenses with coloured lights filters in i the approaching driver’s line of vision. ’ Each headlamp is oval and contains two 1 parabolic reflectors. The upper one has j | an orange-coloured glass filter in it, in place the oidiaary lens; the lower

one has blue glass. . At the right-hand side of the windscreen, in front of the driver and in his line of sight, a box having different coloured viewing filter glasses is placed. These glasses 4ake the form of flat transparent sheets having the same colours as the lights. For ordinary driving, wh,en the bright lights are not in use they remain out of the way, but when filter is pulled down by means of a knob into the viewing position the corresponding bright lights are switched on at the headlamps.

CARE OF THE GENERATOR.

Although the importance of lubrication cannot be over-emphasised, nevertheless it is also necessary to warn the novice owner, and sometimes one who has quite a lot of experience that it is easy to overdo this duty in connection with the electrical equipment of a car or motor-cycle. Maximum efficiency of, these machines can only be obtained from them when commutators are clean. Gradually carbon dust collects, and, .if the oil has been injected too liberally into them will form a paste, which fills up the grooves between the different bars or sections. This causes short circuits, and so reduces efficiency in the machine. It should be scraped out with a pocket knife, or better still, a piece of 3-16 in. steel wire, pointed at one end and bent as may be necessary. The commutator of a belt-driven dynamo, or a starter motor with exposed Bendix drive, may quite easily be rotated as each groove is scraped in turn, but where the drive is of the positive enclosed type, it is necessary to revolve the engine slightly after scraping each groove. In order to watch the commutator while doing this, it is advisable to engage the top gear and push the car • gently, and it can then be seen that none of the grooves are missed. It should not be necessary to remove the spark plugs to do this, as the car is only moved a few inches, and this short distance is covered in a series of jerks. When every groove of the commutator has been cleaned, the tyre pump should be directed on the commutator and adjacent parts to blow out all the loose dust. Having made sure that the brushes are all ni good condtion and are free in their guides, the commutator may be tested by watch the ammeter. When the engine is running, the ammeter hand should be perefectly steady at all speeds. If it is found that the commutator is discoloure4 or scored, remove the brushes and hold a piece of dead-smooth glass paper against the rotating commutator with the engine running until a good polish is secured. This should be done before the- grooves are cleaned, so that the copper dust is removed along with the carbon dust. Before replaping the bushes it is advisable to apply a very slight smear of vaselin or paraffin wax to the commutator as a lubricant. MOTOR INSURANCE. SHOULD IT BE MADE COMPULSORY? LIABILITY OF MOTORISTS. Compulsory insurance becomes effective in Massachusetts on January 1, 1927. Over half a million cars will be affected. Schemes are under consideration in other States. It is estimated that only one quarter of the 20,000,000 motor vehicles in the United States are insured. If compulsory insurance becomes universal the annual premium payment will total nearly £80,000,000. Strangely enough the American Automobile Association is opposed to compulsory insurance. It is contended that it will breed recklessness and that it is unfair to make motorists pay £80,000,000 annually to afford protection against the number who are not financially responsible. The thinking motorist will not agree with either of these arguments. It is absurd to assert that any recklessness will show a material increase. If insurance is only paid on damage in excess of £5 or £lO the motorist will not generally risk, damaging his car. In fespect to the second contention it would seem that America, with its cheap cars, must contain a large proportion of drivers who would not pay for the most paltry damages. There are several millions of cars in America which cost their owners less than £125. Many must be owned by people who could not afford to run a car at colonial prices. Several automobile associations in New Zealand (says a northern writer) have approved of the principle of compulsory insurance. Compulsion is necessary for some drivers. Even owners of expensive cars occasionally refuse to take out a policy. If ‘ they have an accident through their own : negligence they may be open to a claim for more than the value of the car. Again, the motorist should .be insured against third j party risks. There is a class of pedestrian who takes daily risks and relies on the motorist to give way. The same person is usually prompt with a claim for damages I if he is injured. Irrespective of the extent of his own carelessness, he will assume that the motorist always pays. This is a popular I fallacy. It Is very certain that the motorist I pays too often out of sympathy. When a pedestrian is hurt and the | motorist has committed no breach of the by-laws or Motor Vehicles Act, he should make no offer to compensate. An offer of money after an accident will usually be accepted as an admission of liability. It pays to seek legal advice before compensating with the type of person who assumes that motor ownership is a proof of wealth. When a car is insured the insurance company will be responsible for defending any proceedings, and the motorist should not concern himself with sympathy. If the motorist has been careless the injured man will undoubtedly get adequate redress, and the insurance company must pay. The criminally reckless driver can be easily checked under a compulsory insurance scheme. His policy can be cancelled and fitting penalties imposed for the use uninsured car

THE URGE FOR COMFORTABLE CARS. Comfort in the motor-car was the last development which the manufacturers aimed at, but it has reached such a stage of perfection to-day that one’s choice in securing the embodiment of the latest ideas must be executed carefully. From the days of the first car, when the manufacturer aimed at improving the engine and transmission, comfort has been slow in developing, but this can be readily understood when it is remembered that many difficulties had to be surmounted from the start. In early times those who rode in the motor-car did not expect comfort. As long as the engine could work up enough revolutions to propel the machine, the experience of having ridden in a car was sufficient thrill. Motoring at the start was regarded as a hazardous business, and only to be indulged in by those who were fond of strenuous exercise. There was no demand for comfort. The main thing was traction.

LAWS AND MOTOR DESIGN. Broedly viewed, one might define car design as consisting of the appl.cation oi Nature’s laws and dodging those devise i by mankind, writes T. L. R. D’Urville in The Motor. In our endeavour to obtain a much as possible for the least amount o expenditure, the present system of car taxation has inevitably led to small engines and high rotational speeds, because, in the last analysis, we are only conce.nec with consuming a given amount of fuel for conversion into a suitable form oi energy to perform a set task. This situation is now confronting us with 6000 or more r.p.m. for the engine, while in order to consume still more fuel with the same cubic capacity the mixture is forced in at high pressure by superchargers operating at speeds anything you please from 20,000 r.p.m. and upwards. While no objection can be made to such solutions in carefully tended stationary power plants, it is at least questionable in the automobile. It may be urged that it is meeting with a measure of success in racing; but racing cars are not used or illused as is the average passenger car. Furthermore, it is quite immaterial whether the racing car is practically “junked” after its short but dazzling career; advertising is admittedly an expensive, albeit profitable, necessity these days. True, many racing innovations have found their place in the ‘•'ommercial article,” but this is merely becax»-:° such features were practically sound and readily applicable. In this matter of inordinate increase of engine speeds one does begin to wonder what is going to be the price to pay in reduced span of life of the mechanism and consequent annual depreciation. Without entering into technicalities, it may be stated that high rotational speeds are more detrimental to engine life than an equivalent increase of pressure to obtain identical results. Unfortunately the characteristics of the internal-combustion engine are such that it will not “stomach” pressure increase at low speeds, as anybody knows who has driven a car on a hill too steep for the gear ratio selected. Not only is it useless to open the throttle wider, but it is necessary to retard the spark, which means reducing the pressure on the pistons, and, finally, it comes to a change down, which means speeding up the engine in order to allow a subsequent pressure increase to overcome the grade. Curiously enough, it now looks as if human-made leglisation >n the form of the proposed petrol tax will tend to d scourage this high-speed trend, because it will no longer yield the additional power tax free. 1 In any case, the question of car life, as i affecting the rate of depreciation, has not I generally received the attention its import- i ance warrants, yet its bearing in the gen- ] eral maintenance budget greatly overshad- I ows the possible saving in the fuel bill. I

For a yearly mileage of 5000 a saving ef as much as 20 per cent, on fuel consumption at 35 m.p.g. figures at, say, 50s, while depreciation may easily vary from £2O upwards. The prospective car buyer should therefore disregard the customary sales arguments based on fuel consumption and so forth and preferably focus his attention on the “depreciation curve” of the car considered. A good guide is to remember that the second-hand value of his purchase is liable to be in inverse ratio to the “revving” possibilities when new. Another trend in car design, more in keeping with sound practice, is making headway of late, namely, streamlining the vehicle as a whole. This may be regarded as a practical lesson from racing. Should the abolition of the present 20-mile speed limit take effect, we may look forward to more general and bolder progress in this direction. Even if we cannot boast an Auto Strada like Italy, the value of streamlining will assert itself in the higher car speed ranges feasible on most of the highways throughout the length and breadth of the land. It will be found that proper “fairing” * rather moss than tha attempts

I and suggestions one comes across, amounting to a bulbous tail to house a few suitcases i and other odds and ends. It is quite pos- ' s’ble that it will affect the orthodox appearance, seat’ng arrangement, and chassis details of present types. Doubtless the massproduced car will continue for a long time to ’ barge” its wr.y through the air until even the average man feels out of date •. hL rig and demands the latest in body 1 s to pronel him at a fraction of the cost (1 by his Cubist possession. As has "vriably been the case, the change over w li start at the upper ranks of the motoring public, the smaller fry gradually following suit. •

i THE BRITISH TAX ON HORSE POWER. A correspondent of a leading British motor journal, no less a person than the I secretary to the Minister of Transport, in combating the view that the tax on horse I power is detrimental to the British maker iof cars, puts this debatable question in a new light. He says: “I maintain that, inequitable as the horse power tax has been, it has had a very serious influence on the English manufacture of motor cars, and that had it not been for this tax the light car of low horse power and high efficiency would never have come to have been the main product of this country and the admiration of the world. “The imposition of this tax caused the British manufacturer to produce a car • which, in a large way, avoided the tax and had a market unattacked by American massproduction vehicles. “You say in your article: ‘Any big dealer can point to the difficulty of selling a car with a high rate of tax.’ This is one of the incentives that has directed British buyers to a car like the Morris rather than the Ford. Does anybody seriously contend that light British cars would have got to their present prosperity if the Ford had not, in this country, been carrying the burden of £24 a year? Had it not been for the horse power tax, it might well have been that the American cars with their mass production would have swept every manufacturer off his feet in this country.” In the course of his answer to the above, the editor says: “Cannot the Parliamentary Secretary of the Ministry of Transport»grasp the simple fact that a high tax discourages the home demand, and that without the home demand quantity production on a scale to bring down manufacturing costs to a competitive figure ? But for the horse power tax many people would own and use two or more vehicles. The present system deters many from doing so. American care have the advantage of their big home market in a country where no such handicap applies as that enforced upon British manufacturers by taxing care on the width and number of their cylinders. Remove the present system of taxation and substitute one which makes use of the main basis for collecting revenue, and we venture to predict that a better state of things would prevail in the British motor industry.” COMPRESSION. The loss of compression in one cylinder upsets the balance of the engine and the various forms of crankshaft balancers are rendered useless if one cylinder is weak. Unequal compression is the cause of much uneven running, but it is often the last fault suspected. Most garages can test compressions accurately by screwing a gauge into the spark plug thread. Any manometer graduated in pounds per square inch can be adapted, but it should be capable of showing small alterations. Most engines work best at 901 b. to the square inch, or at a compression ratio of sto 1. A mixture of one part of air and five parts of petrol at 901 b. has an explosive pressure of 4501 b. The same mixture at 601 b. exerts only 3601 b. explosion pressure, and at 451 b. the explosive force falls to 2701 b. A fair estimate of compression relations may be formed by turning the engine over by hand. In trying compression, it is advisable, to carry out the work in a place which

is perfectly quiet. Turn the engine over at an even pace, and while doing so note only the relative pressures felt on

each cylinder. If they are noticeably unequal, then, with the assistance of a second person to do the cranking, listen closely for any hissing noise. The sound may come from a point, as, for instance, at the sparking plug or a valve cap; it may come from the crank case, indicating piston rings that are not gastight; it may be heard at the exhaust valve guide or at the intake, which will suggest defective valves or clearances. Any blowback through the induction pipe will have its effect on carburettion and on starting.

Excessive clearances in valves mean restricted passage for the explosive mixture through too late opening and too early valve closing, and for the inlet that not only tends to conditions making for an attenuated charge, but to a certain amount of vacuum against which the engine has additionally to work; in the exhaust it tends to back pressure. When compressions are weak owing to lack of clearance the defect is rather more serious with exhaust valves, and rather more common jyith them than with the inlets, since the stems are much more liable to stretch under the greater heat to which they are subjected. It should be understood also that exhaust valves are much more liable to damage than inlet valves, and require grinding more frequently. Exhaust valve clearance should exceed those of inlet, .0035 in. being sufficient for latter, .005 in. for exhaust.

Weak valve springs also reduce the efficiency of an engine. Again, the trouble is more likely to be found at the exhaust than at the inlet valves. Sluggish action of the springs will prevent full and proper egress of the spent gas. . The efficiency of the exhaust valve springs may be tried out by increasing their compression by means of a screwdriver. If the engine speeds up when the compression is increased, a new spring should be fitted. In grinding a valve, no amount of time or energy will avail if incorrect methods are adopted. The grinding compound should be the finest emery or crocus powder, mixed with oil, and applied to the seating surface. The valve should on no account be turned round and round in one direction without intermission. Such procedure only forms a series of grooves or rings round the circumference of both valve face and seating. The result may appear satisfactory, but will not be gastight. Paste should be used sparingly. The valve should be brought vigorously down on the seat, but should never be turned completely round. Simply keep rotating it to and fro within a third of a complete another point farther round again through circle. Raise it again and rotate from a third of the circumference. Time should be saved by a light spring, passed on to the stem to raise the valve automatically in the intervals of grinding. Occasionally examine the valve and seat and apply further paste sparingly if required. Compression may be lost through loose spark-plugs, either owing to damaged washers, insufficient tightening, or what is worse, through loose porcelains or loose electrodes, which will cause preignition and over-heating. If a loose porcelain does not actually collapse and blow out it is very liable to crack and lose its property as an insulator, causing over-heating and again leading to loss of power. WHEEL WOBBLE. The usual amount of inclination required is about 3 degrees; more or less than this amount having been found in practice to give a tendency for the road wheels to wobble. If a motorist finds that the wobble is gradually increasing, it would be well for him to remove both front wheels and check the angles of the pivot. The car must, of course, be supported on packs beneath the axle pads and held exactly at the normal height provided by the tyres when correctly inflated. Partly owing to the advent of balloon tYr*“ Mid the general increase in road

speeds that has taken place, steering troubles have again come to the front after an absence of several years. Many faults can, however, be traced to an incorrect inclination of the steering pivots, which, in turn, gives an incorrect castor effect.

If the inclination is considerably greater or less than the 3 degrees already mentioned, wedges can be inserted beneath each spring to rectify it, placing the thick end of the wedge at the front of the spring in order to reduce Che angle, or at the rear to increase it. The wedge itself, should, of course, be interposed between the bottom leaf of the spring and the spring pad formed on the axle, if the car has semi-elliptic springs fitted above the axle. If- however, they are underslung, the reverse procedure would be followed. An easy method of calculating the sizes for the wedges can be made by taking linear measurements. For instance, a wheel 30in. in diameter has a circumference of approxinately 94in. and 3 deg. is, of course, 120th of a complete circle, so that 94 divided by 120 should give the measurement on the outside of the tyre, very nearly. This dimension is .78in. Suppose, however, the dimension reads 1.56 in. then a wedge of 3deg. taper would be required. A calculation similar to that outlined for obtaining the inclination of the pivots can be used, taking proportionate amounts for the thin and thick ends of the wedge, compared with the radius of the wheel. In our hypothetical use, assuming a spring pad length of 3in. the total amount of taper required would be 3 divided by 15, or onefifth of the amount at the tyre radius, which, in this case, equals .156 in. There is no doubt that wheel wobble is more likely with quarter elli’ptic springs than with any other type. Certain quarter elliptics are specially designed to counteract the tendency, but the majority of manufacturers of cars once sprung in this fashion have turned their attention to half elliptics as the easiest solution. There are, of course, several light English care with a satisfactory type of quarter elliptic front spring. Most quarter elliptics are nevertheless open to suspicion, and the buyer of a car so equipped should investigate the history of a well-used car to satisify himself that the springs will not produce a troublesome steering effect after use on bad roads. A leading American company made several efforts to re-design the quarter elliptic springs which were fitted to their products for over ten years. Failing to obtain absolute satisfaction after numerous improvements, they adopted half elliptics in 1924 and automatically solved a long standing steering trouble. DIRECTION SIGNALLING. | Direction Signalling appliances as a substitute for hand-signalling have occupied the attention of inventors a good deal recently, but no special apparatus has been taken up as yet. Mr. C. L. Lovegrove, of Wanganui, offers his solution of the problem in a simple device, which on description has merits. Fitted to a stock model Essex car, says the local Chronicle, the device consisted, briefly, of a light bar crossing the windscreen, either at bottom or at top, and light movable indicator rods at each end of the bar. Controlled by a small handle inside the car, the rods move easily, and indicate direction. If the car is holding to its course they point straight ahead, while if the car is turning to right or left they furnish adequate directions for other traffic. Pleasing features, which contribute much to the very obvious value of the arrangement, are that in the daytime the rods are so painted as to be conspicuous without being garish, while at night their purpose is served by red or blue lights which shine from the ends of the rods. The lighting arrangement—showing one colour ahead and the other towards the rear—is automatic, and quite ingenious, and sets the seal of finish upon the appliance, which can be left in position while the driver is making a turn, and thus allows him to control the car with both hands, or sound his horn to complete his warning to other users of the road. The lights can be seen from the rear, and also from the front, even with the headlight full on.

Per Cent. Year. ' Open. Closed. Closed Cars. 1919 . 1,496,652 161,000 10.3 1920 . 1,563,022 320,136 17.0 1921 . 1,179,000 335,000 22.1 1922 . 1.691,368 715,028 30.1 1923 . 2,434,360 1,259,877 34.0 1924 . 1,845,803 1,397,482 43.0 1925 . 1,676,171 2,163,131 56.0