US. MIL. STA. NO. 1 S.F. CAL. / CAVITE, P.I.
Purple Straight Line Cancel
Period of Use: August 13 to November 16, 1898

1898 AUGUST 13: CAVITE to MASSACHUSETTS

EARLIEST RECORED USE

Ref: Goodale A-2 / Baker S-1. This is the earliest known use of the postmark. Previous ERU is September 29 (Philippine Postal History 1898 - 1896, Nocom collection, under "NUMBERED STATIONS" Cavite page). 

Prior to the September 29, 1898 ERU date (Nocom collection, Ex Chiong and Lange) which I recorded in 1994,  the ERU recorded by Goodale's was October 21. Latest recorded usage is November 16, 1898. Now after ten years we have a new ERU.