I'm willing to go with the clock maker chisel guess, or that it's a chisel for fine furniture carving or wood sculpting. It is, however, exactly the same length as leather working tools I used to have. I believe that specific tool is called a "veiner" because it's most often used to carve the veins of leaves into the leather. My tools were chromed and significantly younger than that, but fine leather work using tools like that has been done for a long while, so a hundred year old tool conceivably could look like that. Give us some context: where did you get it, and what was it with?