Powles was involved in numerous companies, typically as a major shareholder who was also chairman. Powles, Brothers & Co. refers to a London company set up by Powles and two brothers, having dealings with Latin America.
In the mid-1820s Powles was heavily involved in the promotion of South Americanmining companies, and enlisted a young Benjamin Disraeli to write pamphlets promoting these mines, particularly those in Chile. Disraeli gained experience and material for his first novelVivian Grey, in which Powles and his wife appear as Mr and Mrs Millions. But speculation in shares caused Disraeli to be saddled by debts, and these took decades to pay off.
South American satrap
In 1823 Gran Colombia applied to Powles for colonists. They came, in the form of the Topo Valley settlers, Scottish and Irish, but the colony was unsuccessful. The British government under George Canning decided to recognise the new Latin American nations, created by the rebellion against the Spanish Empire, at the end of 1824. Shares in South American mines leapt in value. Powles was the most active British merchant in Colombia at this period, operating through local agents. In the area of present-day Venezuela, his commercial dominance was very marked, and persisted for nearly two decades. He weathered the financial storm of the Panic of 1825, and continued with South American mining ventures, and a Gran Colombia loan. The Colombian Mining Association, a company set up by Powles and others, acquired mines in Antioquia State and Mariquita. William Wills went out from the United Kingdom to Bogota for the Association in 1826, and settled in South America. Powles was involved also in the creation of the St. John d'el Rey Mining Company in 1830 and served as its first chairman. An associate and founding director of the company was James Vetch.
Business reputation
During the 1850s, the business methods used by Powles came under intense criticism from the barrister Christopher Richardson. His banker father, of the same name, has been identified tentatively with a director of the Chilean Mining Association with which Powles was involved in the 1820s. Deas, writing in the Oxford Dictionary of National Biography, which calls him a "company promoter and speculator", comments that some of his activities "would now be considered fraudulent", though they were not illegal.
Death
Powles died at Elstree in 1867. He was buried in Elstree churchyard, where two of his sons already lay.
Family
Powles was married three times:
He married in 1808 Louisa Chambers; they had two daughters and a son, and were divorced in 1815. The son John Richard Powles was a merchant in Colombia.