Opinions of Butterford Eelwart are both contradictory and fiercely held. Some claim he is a genius whose talent for invention has been sadly curtailed by the carping of lesser minds. Others claim with equal vehemence that the man is a fool and ought to be locked up for his own safety. Within this second group is a more reasonable faction who are willing to allow him to remain at liberty, provided he is allowed nothing to write or draw with other than thick wax crayons. They believe that even the most naive of artisans will beware of engineering drawings presented to them scrawled in green wax crayon.

I confess I tend to stand aside from the debate, having known Butterford for many years. Indeed I confess I quite like the chap. Still I feel that he should be judged mainly by the quality of his work.

His first invention was…