Series Is Presented Here As Two Variables--(1)--Seasonally Adjusted, 1907-1942 (3)--Original Data, 1943-1971. Data Are For The Wednesday Nearest The End Of The Month. Source: Data For 1907-June 1919: Friedman And Schwartz, Monetary Statistics Of The United States (NBER, 1970), Table 27, Column 2, Pp. 402-415. Data For July 1919-1942: Computed By NBER By Summing Series 14185 (Vault Cash, Member Banks) And Series 14184 (Vault Cash, Nonmember Banks).
This NBER data series m14126a appears on the NBER website in Chapter 14 at http://www.nber.org/databases/macrohistory/contents/chapter14.html.
NBER Indicator: m14126a
Release: NBER Macrohistory Database
National Bureau of Economic Research, Vault Cash, All Banks Except Federal Reserve Banks for United States [M1426AUSM027SNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/M1426AUSM027SNBR/, August 3, 2015.