[4][5] Enoch Clark got his start in finance by working as an office boy[6] at S. & M. Allen & Company, a prominent Philadelphia bank.

[7] (After she died, her son Edward White Clark commissioned a stained-glass window in her memory in the First Unitarian Church of Philadelphia.

[2] The firm opened branches in New York City, St. Louis, New Orleans,[6] and Burlington, Iowa,[10] and made considerable money performing domestic exchanges in the wake of the 1836 revocation of the charter of the Second Bank of the United States and the Panic of 1837.

Cooke was assigned to the clerical department where his devotion to his work and his exceptional abilities in financial matters caused Mr. Clark to push him along," a 1914 history of the firm recounted.

[11] At the outbreak of the Mexican–American War (1846–1848), the U.S. government borrowed about $50 million (about $1,695,555,556 today[12]) from the firm, then recognized as "the leading domestic exchange house" in the country.

(Cooke retired from the firm in 1854, and went on to help to sell the bonds that financed the U.S. Civil War and push the cash-strapped American government to form a true national currency.