Norwich bulletin., 1913-03-26
Cluett. Peabody & Co.

space of time.
 At high speed the wheels of motor
 car slip on the surface of the road to a
 degree scarcely reckoned with by the
 average driver. Friction of the most
 violent kind results-burning, wear
 ing. destructive friction. At a speed
 slight but constant. When a mile a
 minute speed is attained the friction
 Is increased out of all proportion to
 the increase in speed. At this speed
 It Is estimated a 36 inch wheel will slip
 about six complete revolutions during
 each mile Cor minute} travelled. This
 will amount to total slipping of 3,60O feet every hour that a mile a minute speed is maintained. Therefore it will
 be readily realized what 8 tremendous amount of wear is imposed on a tire when fast driving is indulged in.
 When the greatest amount of slipping takes place it is hardly probable that the tires are bearing the full weight of the car, as it is the continua. bouncing at high speeds which causes the wheels to turn more rapidly than the road un- der them, but the wear on the tires is tremendous. The best evidence of this kind of friction is seen at the average road race. when tires are changed fre- quently in. a run of 100 miles.
 If the air in the tire is already compressed before the shock is receiy- ed the additional compression or ab- SOrption of the shock will not be 50 marked as if the tire were not pumped so hard" On the other hand, a tire containing only a small amount of air pressure will be exceedingly suscepti- ble to depression of its tread when an obstacle is encountered, and the rub Der at the point of contact may be flat tened almost to the rim. Thus hard tire is enabled to encounter a great many abrupt inequalities in the road, but will not absorb slight shocks and jars, while a, soft tire is sensitive to even the slightest obstacle in the road, but will be overtaXed at the first sug- gestion of rough going"
 Noise in the differentia is not al ways sign of poor fabrication, but is often due to faulty meshing of the gears. A hum or singing note is pro duced when the driving bevel meshes too deeply in the differential bevel. Moving the two further apart, Into the correct relation, will stop the noise. Most cars have an adjustment for this purpose
 Austria has initiated Germany in inn posing a tax on motor tourists. For an automobile or a motorcycle the automobile can stay for three months before it becomes subject to the ordi- nary annual taxation. but the motor cycle only one month.
 Automobiles now afford such good Westher protection, with their wind shields, tops and side curtains that it would be a real pleasure to drive through a rainStorm on tolerably good roads, if it were not for the fact that the rain covers the wind shield with fog and obscures the view.
 When a motor has been taken down for a thorough cleaning, it is good plan before putting it together to rub into the dry surfaces of the cylinder walls. pistons, rings and the main connection rod and piston pin bear ings-in fact, all points where there is friction-gTaphite mixed with cylinder oil to the consistency of a rather thin paste. If the lubricant is applied with a swab on the end of a stick it will be less disagreeable to handle It should be vigorously rubbed in and then most of it wiped off. The theory is that the graphite lays a good foundation for subsequent fabrication and insures good start without danger of early cut ting or scerong of bearing surfaces
 Where motors have been run for a long time the cams, filters and ends or the valve stems may have worn sufh- cientIy to reduce the effective lift of the valves, whereupon there will be loss in power so gradual as to be over looked or to be attributed to other causes. The inlet side is less likely to be affected in this way owing to the fact that the valves are not open ed under pressure, The remedy IS either in a complete renewal of such parts as may be found to be much worn or else a bufld-on of patches The last named remedy, however, be- sides being most difficult to accomplish is not wholly satisfactory, though It is an expedient worth knowing.
 If there are any doubts in the mind of the operator to whether the mix ture fig too rich, an excellent way to ascertain the correct proportion Of air and gasoline is to shut off the fuel at the tank and open the thottls- If the passing into the cylinders IS too rich the engine speed will increase as the level of tiae gasoline in the float chamber IS lowered, sinee the ep- eratian weafzeHs the mixture eohsld- erably, If the mixture is thought to be toe weak, the float chamber can be flooded while the engine is running, and if this causes the motor to speed up It may be taken as an indication that the mixture is not rich enough.
 In the use of the injection type of gasoline primer, or starting device, the same precautions are necessary in pri1ning the ordinary carburetor. Too much gasoline pumped into the cylin- ders will not vaporize properly. and will tend to choke the combustion chambers with an over-rich and un- burnab1e mixture. If the engine fails to start the spark afte- the first SnOt II IS pSIter 10 SSC out. grasp the crank firmly in the left hand. and wind her up" in the eid- fashioned and despised way. than to butter with the starter.
 Adjustable pedais are a great i'm provement to the control system, but for proper results they should be ad- justsd to suit the needs of the indi- vidua1 driver Usually the changes in position of the foot plates are so cas- fly made that this can be done as fre- quently as may be necessary and in a few moments time. One thing to re- however. is that the adjust ments should be positive A loose pedal is almost as distracting as gear set with imperative spring latches.
 To involve logically the national governm ent in the highways progress of the country and to further discus sion and action which shall produce a plan satisfactory to the roads advo- cates of the various states, is the con- crete reason given by the A. A. A. National Good Roads Board for call ir0 Go01rH Fe5ovo1 (THaH