A predecessor of the taxicab, the herdic was a small two wheeled carriage that had side seats and an entrance at the back. The major improvements over previous types of carriage were in the springs, the way the body was mounted on the springs, and the manner in which the axles, springs, body and shaft were connected. Herdics were designed as passenger vehicles, and, in particular, for use in public transportation. Their low entry made it easy for passengers to enter and exit the cars. The first herdic cabs carried up to eight passengers.
The earliest herdics were painted bright yellow and quickly acquired the canary nickname. Each cab was small enough to move freely through the city streets of Williamsport and leave its passengers at the curb instead of the middle of the street was other modes of public transportation were forced to do.
Peter Herdic had moderate success with his cab and it was soon adopted in the cities of Boston, Philadelphia, New York, Washington, D.C., and numerous other cities. The herdic cab was in service in Washington as late as 1918