After leaving Sedgwick in Wales, Darwin spent a week with student friends at Barmouth, then returned home on 29 August to find a letter from Henslow proposing him as a suitable (if unfinished) naturalist for a self-funded place on with captain Robert FitzRoy, emphasising that this was a position for a gentleman rather than "a mere collector". The ship was to leave in four weeks on an expedition to chart the coastline of South America. Robert Darwin objected to his son's planned two-year voyage, regarding it as a waste of time, but was persuaded by his brother-in-law, Josiah Wedgwood II, to agree to (and fund) his son's participation. Darwin took care to remain in a private capacity to retain control over his collection, intending it for a major scientific institution.