Memorial in which Massey outlines improvements he had made to his sounding machine and cites testimonials in support of his invention. He mentions that the Royal Navy had ordered 750 of his machines, but describes the poor remuneration he had received, in the hope of convincing the Board that a patent should not be grounds for exclusion from eligibility for a reward. He also lists the terms of the rewards and of rewards made to previous inventors, stating that he too should be 'liberally rewarded' as his invention would save 'ships, lives and cargoes'. The memorial was originally enclosed with a letter from Massey to the Board of Longitude [RGO 14/31: 115-116].