Thomas Edison tried two thousand
different materials in search of a filament for the light bulb. When none
worked satisfactorily, his assistant complained, “All our work is in vain. We
have learned nothing.”
Edison
replied very confidently, “Oh, we have come a long way and we have learned a
lot. We know that there are two thousand elements which we cannot use to make a
good light bulb.”
No comments:
Post a Comment