
Fog could cover French movements, as when the Brest fleet sailed in April 1799. Once it had sailed, the British were unsure whether the French would head for Ireland or the Mediterranean. Concern about the safety of Minorca handicapped the subsequent British pursuit in the Mediterranean, and the French were able to sail to Toulon, and eventually back to Brest, without being intercepted. In January 1808 the French Rochefort squadron evaded the British blockaders in bad weather and poor visibility and sailed to Toulon. Fog was also a hazard to British warships. The 74-gun Venerable, part of the squadron covering Brest, sank on the Devon coast in 1804 after running ashore in a thick fog.