THE CARBURETER.--In the past carbureters have had a bad reputation, probably, deservedly so. The great difficulty with most of them has been in the floats, and the float connections with the inlets. This, and the fact that small particles, which somehow get into the oil, and block the flow at the needle point, and the presence of water, are the serious troubles. One can be remedied only by a thorough overhauling, and the other by using special care in filling the tank with fuel. The float chamber should be kept clean, as well as the ducts and valve controlling the flow. Sometimes a small fiber will be lodged somewhere in the pipes, and this will catch small particles, and temporarily arrest them. The accumulated mass when dislodged blocks the valve, and the mystery seems inexplainable. _Wrong adjustment_ in a carbureter manifests itself in three ways: If the smoke is black, and the flame is red, the mixture is too rich; a yellow flame indicates a lean mixture; and a blue flame and clear exhaust shows that it is properly set. If an explosion takes place in the muffler, it is an indication that gasoline, or the vapor, has been carried over; and white smoke discharging from it shows that there is too much lubricating material going into the cylinders. _Weather_ will affect mixtures, and more air is generally required on a hot day than during damp weather. This explains why a machine will run without trouble with a certain adjustment one day, and be very unsatisfactory the next. These things should be observed and mentally noted. CHAPTER XVII ELECTRIC VEHICLES The construction of electrically-equipped cars is one which requires pages of explanations and illustrations to do it justice. The scope of the present work was originally intended to cover only gasoline-driven cars, so that this chapter, which in a measure only sets forth the manner in which such automobiles are built, will more particularly point out the mechanism which pertains to the operation, and the care needed to maintain them. It is a long and difficult study to understand the electrical details necessary to build, repair, or maintain electric cars, but it is part of the general mechanic’s duty to understand where the troubles lie, when the mechanism fails to respond, and most of the electrical devices are now so made that the ordinary mechanic is able to make repairs, even though he may not have a technical knowledge of electricity. Within the past five years this type of automobile has been improved to such an extent that it is steadily gaining ground, and their use growing to such a degree that it may soon become a great rival of the gasoline car, especially for pleasure purposes. There never has been any question as to the value of electric motors for traction service. Wherever a current of electricity can be distributed and transmitted to a motor, it is the most satisfactory method of moving vehicles, as has been shown in street railways.