Background and early life
Mungo Ponton was born on 20 November 1801, the only son of John Ponton, a farmer at Balgreen near Edinburgh.
After leaving school he was apprenticed to the solicitor James Balfour. He was later apprenticed to William Scott and G L Finlay. He himself was admitted to the Society of Writers to the Signet in 1825.
By 1829, Ponton was in partnership with Archibald W Goldie WS, in the firm of Goldie & Ponton.
National Bank of Scotland
National Bank of Scotland was established in Edinburgh in 1825 and from the outset Ponton’s partner Archibald Goldie served as its law agent, undertaking legal work and offering advice as required.
In January 1838 Mungo Ponton became solicitor to National Bank of Scotland. Unlike Goldie’s previous role as law agent, this appointment was as an employee of the bank, with a salary, office and staff. The partnership between Ponton and Goldie was dissolved and Ponton went to work for the bank full-time.
In 1840 Ponton became secretary of National Bank of Scotland in addition to his continuing role as company solicitor.
By the mid-1840s he was in poor health. He was granted an extended leave of absence in summer 1845, but by winter he was still very unwell. The board granted him another leave of absence in June 1846 so that he could travel to Germany to take the waters. His health did not improve, and in September he wrote to the board from Coblenz, tendering his resignation from the bank.
The following February the board resolved to continue paying him as solicitor, in the hope that his health would eventually recover and he would be able to return to work. They reserved the right to call upon him for legal advice, but there is no evidence that they ever did so. It is not clear how long this arrangement continued.
Inventor and photographic pioneer
Mungo Ponton became a fellow of the Royal Society of Edinburgh in 1834. In 1838 he was awarded a silver medal from the Society of Arts for Scotland, for his role in the development of the electrical telegraph. He is best-remembered today, however, for his contributions to photography.
In 1839 he announced his discovery of the light-sensitive qualities of sodium dichromate. These findings were vitally important to the development of photography, paving the way for nearly all the photomechanical processes that later came into standard use.
He continued to experiment with photographic chemistry. In 1845 he was awarded another silver medal from the Society of Arts for Scotland, this time for his development of a process for measuring hourly variations in the temperature of photographic paper. In the same year he also introduced a variation of the calotype process that worked with shorter exposure times.
In June 1830 Mungo Ponton married Helen Scott Campbell, the youngest daughter of Archibald Campbell, an Edinburgh brewer. They had 7 children together: Elizabeth; John; Archibald Campbell; Alexander Campbell; Mungo Stewart; Bethia Katherine; and Matthew Moncrieff. Helen died in August 1842.
In 1843 Ponton married Margaret, daughter of Alexander Ponton, an Edinburgh procurator-fiscal. They had one son together, named Thomas Graham Ponton.
In 1871 Ponton married his third wife, Jane, daughter of Dougald McLean, an Edinburgh merchant. She survived him.
Later life and death
Ponton never returned to good health after his illness in the mid-1840s. He moved to Bristol, where the climate was milder and thought to be more favourable to health. He gave up his legal and banking career, but maintained his interest in science, publishing numerous further papers on scientific and religious matters.
Mungo Ponton died at home at Clifton on 3 August 1880. He was buried in Edinburgh.