I removed the reference to the 1751 Dolphin having copper sheathing - I see from references the next ship named Dolphin did have this, however, I discovered a resource stating the HMS Alarm was first sheated in copper in 1761, which could indeed make the 1751 Dolphin have this sheathing. --Broux (talk) 17:59, 21 March 2008 (UTC)
You're correct that Dolphin wasn't copper-sheathed on commissioning - as you point out, the first naval vessel to be copper-sheathed was Alarm in 1761. However she was copper-sheathed sometime between 1761 (when Alarm was sheathed) and 1764 (when she put to sea under Byron's command).
Sources for this include:
J.C. Beaglehole (Pacific Exploration 1966, page 195, ref in this article) describing Dolphin as copper-sheathed when assigned to Byron's survey voyage in 1764;
J.R. Harris ("Copper and Shipping in the Eighteenth Century." The Economic History Review 19(3) 1966 p.553 - source in article on Copper sheathing) giving detail of the damage to Dolphin's copper sheathing in 1768 "after a period of strenuous service ... in passing through the sea in two voyages around the World" - making clear the sheathing occurred before the first voyage in 1764. I'll add this as reference in detail in this article shortly.
On the basis of the above, have restored the reference to copper-sheathing in this article. Happy to discuss if anyone disagrees. Euryalus (talk) 05:02, 6 September 2014 (UTC)