 Neptune was ordered from Deptford Dockyard on 15 February 1790 , to a design developed by Surveyor of the Navy Sir John Henslow . She was one of three ships of the Neptune class , alongside her sisters HMS Temeraire and HMS Dreadnought . Neptune was laid down at Deptford in April 1791 , receiving her name on 24 July 1790 . The initial stages of her construction were overseen by Master Shipwright Martin Ware , though he was succeeded by Thomas Pollard in June 1795 , and Pollard oversaw her completion . Neptune was launched on 28 January 1797 and sailed to Woolwich to be fitted for sea . Arriving at Woolwich on 12 February , she was immediately docked to have her copper sheathing fitted , a process that was completed by 1 March . Launched again , she finished fitting out , and received her masts and yards . Her final costs came to £ 77 @,@ 053 , and included £ 61 @,@ 172 spent on the hull , masts and yards , and a further £ 15 @,@ 881 on rigging and stores . 
