Dr. Mike Ashton (a powder compact historian) is publishing a compact history of face powder containers.  There are 7 volumes.  1.  Patents, Construction & Early Usage.  2.  Compressed Powder.  3.  Early Portable & Metal Sifters.  4.  Non-metallic, 1920's & Mechanical.  5.  1930's Sifter, Seals and Fashions.  6.  Wartime & Postwar.  7.  Thematic Collections.     Nos. 1 and 2 have been published and the rest are to follow.  If you are interested please contact me and I will send details about contacting Mike.  I have found them very useful already - especially tracing patent numbers!  Each copy is priced at £25 including P & P.