This cover was carried from The Dalles, OR to Canal Zone in 1914. The sender was Marguerite Nielsen (younger sister was 19 at the time) to Dora Nielsen (oldest daughter was 32 at the time). Dora had been working initially as a teacher and later as a supervisor for the government but her position was abolished at the end of June 1914. She took a trip back home (arriving in NY on July 23 aboard the SS Almirante) then back again to CZ before this letter was sent. She was rehired as a teacher (at a greatly reduced salary) in April 1915. So, she certainly was likely to be moving around in October. I see the letter arrived at Balboa Heights on the 21st, then sent to Ancón where it was received on the 22nd. In purple a forwarding note sends it to Cristóbal where it was forwarded again on the 23 to Gatún where it was received on the 28th. My assumption is that is was delivered to Dora. Why did it take so long to move from Cristóbal to Gatún? Looking at modern maps it's just the length of the canal from the Pacific coast to Gatun Lake (under 10 miles) yet it was able to go from Ancón to Cristobal (more like 50 miles) in only one day.
BTW, Dora was a bit of a spinster in 1914, 32 years old and unmarried. She did meet Alfred Bechlem while in CZ and they were married, likely in November 1915. She resigned her position then and didn't go back to work until Alfred joined the active service in 1918. He lived through the war and I believe they stayed married the rest of their lives, though they moved around a bit at least to NY and Wisconsin, but she was buried near Bremerton Washington, so she came back to the PNW at some point and stayed.