As soon as you can get to a telephone, call 911. Explain the situation and give the exact location of the accident, so that help can arrive quickly. Be sure to mention whether you need an ambulance or a fire engine. Remain on the telephone until the operator tells you it is okay to hang up. Or, flag down a passing car and ask the driver to go for help. The driver may have a cell phone in the car and can make an emergency call on the spot.