Critics might question why Byron failed to investigate further, but the reference to sickness in both ships, and his subsequent description of his transit across the Pacific as ‘the longest, hotest, & most dangerous Run that was ever made by Ships’ indicate an interest in getting to somewhere else.
Water was running short, and after sighting ‘Byron's Island’ in Kiribati on 4 July, he reached Tinian at the end of the month. A two-month stay there allowed the crews to recuperate. He put to sea again on 1 October, reached Batavia on 28 November, but remained there for less than a fortnight, worried about the likely toll of the city's notorious unhealthiness; by 14 February 1766 he was at Cape Town and left for home early in March.
When he brought the Dolphin to anchor in the Downs on 9 May 1766, Byron had completed the fastest circumnavigation to date, a twenty-two months circuit, and the first accomplished in less than two years. He had done it, regardless of the niggling concerns expressed in his journal, relatively untroubled by scurvy, and the Dolphin's copper-sheathed bottom survived the voyage in good condition. That advance in naval technology meant that in less than three months she was ready for another circumnavigation under a new commander, Samuel Wallis.
Analysis of Byron's voyage tends to focus on the negatives. There was, for a start, his willingness to forsake what would have been the most significant discovery since 1492 when he failed to investigate those signs of land away south due to indifferent winds and some sickly crewmen.
While he mostly ignored instructions and ultimately made no significant discoveries, Byron's speculation in his journal coincided with the publication of John Callander's Terra Australis Cognita, an almost straight copy of Charles de Brosses' Histoire des navigations aux terres australes (1756).
He reported portents of future discovery, told First Lord Egmont what the Earl wanted to hear and did enough to spur on the Admiralty thanks to the knowledge that the French had similar designs on the southern continent.