To streamline the complex maze of postal services for international mail, 22 countries met in 1874 to establish the General Postal Union, which changed its name to the Universal Postal Union, or UPU, in 1878. The UPU remains in operation to this day, simplifying the exchange of mail among 192 member countries.
The registered cover from 1893 shown in Figures 1 and 2 was sent in accordance with U.S. Post Office and UPU regulations in effect at that time.
It was posted in Philadelphia on February 13, 1893, with 18-cents of postage. That amount would have satisfied the 8-cent registry fee then in effect plus twice the UPU letter rate, which was 5-cents per half ounce in 1893. Presumably this letter weighed between 1/2-ounce and 1-ounce.
That amount of postage was made up by affixing 16-cents worth of stamps on a 2-cent stamped envelope (Figure 3). The two stamps are from the 1893 Columbian Exposition Issue of 1893: the 1-cent depicting Columbus in sight of land (Scott 230) and the 15-cent showing Columbus announcing his discovery (Scott 238). These stamps were issued January 1-2, 1893. First day covers from January 1, 1893, with Scott 230 exist, but the earliest documented use of Scott 238 is January 26, 1893. Thus, this is a relatively early example of the usage of both, especially of Scott 238. The stamp envelope is most likely Scott U311.
The stamps are cancelled with Philadelphia double oval cancels. Those are best seen in Figure 3 on the 1-cent stamp and the envelope embossment.
The front of the envelope includes the registry label shown in Figure 4. Scott catalogs those labels; this particular one is Scott FX-NY1b(ii). Beginning In 1882, the UPU required that all registered mail bear a label or impression with a capital "R." The U.S. Post Office opted for a label. There were a couple of dozen postal facilities around the U.S. that handled international registered mail, with the one in New York being by far the largest. That was the office through which this letter traveled.
The back of the envelope has four auxiliary markings highlighted in Figure 5:
A February 13, 1893, Philadelphia registry mark;
Two February 14, 1893, marks applied in New York: a registry mark and an encircled "B" that I assume was the postal clerk's mark; and
A circular date stamp dated February 25, 1893, from Frankfurt, Germany, the cover's final destination.
Despite having the sender's name and address in Philadelphia, I can find no information on that individual. The recipient's name was the same as the sender, so they must have been related, or it is even possible that the letter was self-addressed.
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Figure 3
Figure 4
Figure 5