Fishing has long been important in the Korean and Japanese economies. While coastal fishing was the major source for marine foods in the past, beginning with the first “Five Year Plan” in 1962 Korea has increased its harvest of deep-sea fish by more than twenty-fold.
The Government General of Chosen seems to have undertaken a study of the currents along the Korean coast in 1934 (Showa 9). The value of such information is most useful to fishing industries, as well as to the shipping industry. The illustrated item is the return half of a double card dispatched in a bottle and carried by ocean currents. A portion of the Kuroshio, which flows north from Cheju Island into the Eastern Sea brought the bottle to Japan. It is known as the Tonghan (or East Korea) current by the Koreans.
From the reverse side of the card comes the information that the bottle bearing the card was put into the sea in May, 1934 and found near southern Akita Province about two months later (a 1000 mile or 1600 kilometer journey).
The obverse side of the card shows it was posted at Hokuito, Akita Prov., July 29, 1934 (#1). A 13 x 31 mm vertical chop advises that 3 sen postage would be collected on delivery (#2). The two circular chops are receiving marks; the larger from the Marine Laboratory Station is dated August 2 (#3) while the smaller, dated August 21, was applied at the appropriate section of the Laboratory (#4). The card was provided by Frank Allard and the translations were done by Warren Hahn.
Some questions come to mind: what sort of bottles were used to send the cards? What does the missing part of the card look like (note the perforated long side)? and have any intact double units survived?