A thumb-nail sketch of Hammet in the City Biography shortly before his death allotted to him the ‘rudeness, ignorance and impudence’ with which successful parvenus are commonly attributed. He was there described as a Taunton barber’s son of little education, who as a footman in the household of the usurer ‘Vulture’ Hopkins (John Hopkins of Brittens, Essex) made the conquest of his mistress’s sister, the daughter of Esdaile the banker; and owed his rise as a building contractor and his banking partnership to his father-in-law. On his marriage his father-in-law settled £5,000 on Hammet’s wife and Hammet settled the proceeds of copyhold of the manor of Taunton Dean worth £48 10s. a year, acquired not long before, on her. His obituary in the Gentleman’s Magazine described him as ‘a conspicuous example of the effects of enterprise and industry’: although he ‘wanted the advantage of education’, he was endowed with ‘plain common sense and well acquainted with the qualities of mankind’. His memorial inscription at Taunton, referring to his ‘munificence’ to his native town ‘to which he was most zealously attached’, credited him with ‘a clear and comprehensive mind, a fervid imagination and an enterprising spirit’.
In 1790, when he was returned for Taunton on the Market House Trust interest for the third time, after a severe contest, Hammet founded there the bank of Hammet, Jeffries, Woodforde and Buncombe, which drew on Esdaile, Hammet and Esdaile of 73 Lombard Street. In Parliament he continued to give a general and, he boasted, independent support to Pitt’s administration and became a more confident speaker, finding, so he claimed, a better audience there than he did in common hall. On 15 Mar. 1791 he spoke for a meeting of government stockholders who deplored Pitt’s bill to apply half a million pounds of unclaimed dividends in the Bank of England to the public service and advised an adjournment, in the hope that Pitt would reconsider it.
On 28 Mar. 1792 he introduced a bill to make bankers’ private estates liable when they contracted debts: in view of their growth in respectability as a profession, he was anxious that they should not have power without responsibility. At the report stage, however, this bill was sat upon by legal Members, who pointed out flaws in it, 3 May. On 20 Mar. 1795, in the debate on the privilege of franking, he conceded that ‘it had happened to him to frank a great many letters’ (he was said to be making £2,400 a year by sending bills of exchange duty free under his name), ‘but he would be willing to forego it’. On 10 Apr. he came to answer a summons of the House to explain why he had for two years deputed his privilege of franking to his son; he pleaded ‘extreme indisposition’: ‘it was true that, at intervals, he was much better’, but ‘he was this very morning uncertain whether he should be able to attend the House from illness’. He narrowly escaped a reprimand for abuse of privilege.
In his last Parliament he spoke less often: after writing to Pitt of his anxiety at the stoppage of payment in specie by the Bank of England, he twice defended the conduct of the Bank in March 1797. Soon afterwards he was acquitted on a charge of usury at Taunton.