The Canal Zone Postal Service issued the 7-cent Bas Obispo-After commemorative (Scott 125) on August 15, 1939, as part of the Twenty-fifth Anniversary Series. The series includes two groups of eight 'before' and eight 'after' views of the Canal Zone.
This stamp shows the cruiser USS Houston in Gaillard Cut heading north towards the Pacific, the image taken on July 11, 1934. The stream at right is the old Rio Mandingo near Bas Obispo that flowed past the former U.S. Marine Corps site of 1904-1914 known as Camp Elliott.
President Franklin D. Roosevelt, a stamp collector himself, suggested the Twenty-fifth Anniversary Series when he visited the Isthmus of Panama aboard the Houston. (The Japanese Navy sank the USS Houston during WW II.)
Since no seven-cent postal rate existed at the time, patrons combined the Bas Obispo-After with other stamps to make up a specific rate.
Like the 6-cent stamp, the 7-cent Bas Obispo-After did not sell well except on the first day of issue. Of the 210,000 printed, only a little over 71,000 sold, primarily to collectors, who used them on commemorative covers or saved them in unused condition. Sales ceased on February 28, 1941, and the remainders burned on April 12.
This stamp frequently appears on first day covers, most often serviced by the retired US Navy Chief Walter G. 'Bones' Crosby. Non-philatelic usages rarely appear and are avidly collected.