Regarding phone numbers on numismatic correspondence, I found the following in my files: Scott Stamp and Coin Co. letterhead dated July 9, 1935 - "Telephone Bryant 9-1277"; Henry Chapman letterhead dated December 31,1936 - "Bell Phone, Pennypacker 7752; and The Elder Coin and Curio Corporation letterhead dated February 8, 1937, "Telephone Wisconsin 7-8687".

As a related story, many coin dealers during the 1980 silver boom had canvas bags imprinted with their name and address. We used thousands of these in the 1980s at my former work place. In 1995 when I started Chicago Coin Company I ordered canvas bags and requested my website be included under the address. The bag company is one of the larger in the country and no one had ever asked for this. They had to adjust their printing equipment and add a line. We became the first company to include a website on their canvas bags. In 2110 when someone asks the E-Sylum editor when the first website address was placed on a bank bag, this might pop up on the Google of the future.

To read the earlier E-Sylum article, see:NOTES FROM E-SYLUM READERS: DECEMBER 1, 2013 : Query: When Did Phone Numbers Become Commonplace?(www.coinbooks.org/esylum_v16n49a08.html)