Spectral lines: Learning by undoing

Some time ago we suggested that if readers would reveal some of the more significant mistakes they had made, the results might prove a valuable contribution to the profession. We were warned by colleagues that it is just not in the cards for engineers to own up to their mistakes. In fact, after we barged in where others fear to tread, Alfred Zinn wrote to us suggesting that such an experiment could be disastrous. Physicians long ago learned the folly of such exercises, he said, offering this unlikely scenario involving two doctors at a medical convention