She was known as the Carpenter's Mistake, and no one in the service had ever imagined she would be launched. - Post Captain
1803 – 1804: The Peace of Amiens and an anxious journey through France and Spain after hostilities resumed delay Jack’s assignment in Post Captain to a new command until he is given the very unconventional ship-sloop HMS Polychrest, an unusual vessel with sharp ends at both bow and stern, no tumblehome (inward curvature at the top of the hull), drop keels (similar to daggerboards on some modern sail boats), and the remnants of the launching system for an unsuccessful secret weapon (a giant rocket). After several months of service in the English Channel, the Polychrest is severely damaged in a raid on a French port and sinks soon thereafter.
The physical form of the Polychrest (except for the secret weapon) was taken from the Dart class of sloops. The sliding keels, originally designed by Captain Schank, were employed upon a number of small Royal Navy vessels around this period, although problems with leaking centerboard cases perhaps discouraged wider experimentation. Unlike the Polychrest with its extraordinary leeway and a propensity for missing stays, the real HMS Dart and her sister ship Arrow performed satisfactorily during their Royal Navy service. The Dart was broken up in 1809. The poor sailing qualities of Polychrest and perhaps the notion of a new secret weapon were likely taken from HMS Project, a much smaller vessel than the Dart (and Polychrest) with a very shallow draft to carry a new design of howitzer into coastal waters. The Project was broken up in 1810 after only five years of service.
Text and diagrams courtesy of Bruce Trinque. Painting by Geoff Hunt.