other coins as a result, his primary purpose was to promote the sale of his catalogue, and his campaign supposedly led to transit delays in some cities as trolley conductors checked through their change. His actual purchase, for $200, of a rare cent, was also advertised. In his advertisements, Mehl urged collectors to sign up for his "Mehl-ing list". According to a 1929 article on Mehl, he was among the top five recipients of mail in Fort Worth, and during the busier part of the year, ranked second or third, though another source states he accounted for more than half of Fort Worth's incoming mail, leading the post office to put additional trucks on the Magnolia Avenue route. Despite his extensive dealings in coins, the 1929 article disclosed he did not himself collect them, feeling that he could not both collect and deal in coins; instead, he collected autographs. Both his auctions and his fixed-price coin sales were by mail-order only; if a prospective buyer showed up in Fort Worth, Mehl would discuss a purchase and even take the person to dinner, but would insist his guest return home and write to complete the purchase, stating he did not want anyone to feel under pressure to buy. From 1924 to 1926, Mehl served on the ANA's board of governors. In the early 1930s, amid the Great Depression, hobbies prospered, including coin collecting. Mehl greatly expanded his campaign to sell coin books to the American public, who were receptive, liking the idea of finding a rare coin in those difficult times that might solve one's financial worries. Mehl purchased full-page advertisements in Sunday newspapers and had his own nationwide radio program, stating in 1933 that he had spent more than $50,000 () to advertise on more than 50 radio stations. A 1931 advertisement in The American Weekly, a Sunday newspaper supplement, cost him $18,500, while a $2,000 ad in The Saturday Evening Post brought in 9,800 book orders during the first week. Catering to both beginning and advanced collectors, Mehl worked for years to get the noted numismatist, Colonel E.H.R. Green, who made large coin purchases, as a customer; he was eventually successful and sold Green an estimated $500,000 worth of coins. His incoming mail peaked with 1.25 million pieces in 1935. Mehl proclaimed, in 1938, that he had $250,000 in capital, $500,000 in resources and “the largest numismatic establishment in