Kanagawa group plans sea voyage in Jomon-style craft

By Kazuo Takahashi, Mainichi Shimbun, Monday, April 20, 1999

[dugout canoe]
[Members of a Kanagawa-based youth group build a 7-meter-long dugout canoe in preparation for a voyage to Kozu Island, one of the seven islands in the Izu chain.]
YOKOHAMA—When studying history, you sometimes just have to get your hands wet.

One group of industrious youths plans on doing just that. Using handmade canoes, they will this summer seek to retrace an ancient trade route off the Izu Peninsula to study the ancient circulation of stones that were used for arrowheads and other objects crafted from stone, group members said.

Takuya Onishi, 24, a surveying engineer from Kawasaki, and nine others have been building two dugout canoes for their planned journey in mid-July. The trip would take them on a 55-kilometer-long route from Shimoda, Shizuoka Prefecture, to Kozu Island, one of the seven islands in the Izu Archipelago.

The return of the ancient mariners is aimed at investigating the ancient sea route that is believed to have been used to transport the volcanic rock known as kokuyo-seki from the island to Shimoda during the Jomon Period, which lasted from about 8000 B.C. to about 200 B.C.

Many volcanic rocks that orginated on Kozu Island have been unearthed from ruins in Kanagawa, Chiba and Shizuoka prefectures that date back to the Old Stone Age and the Jomon Period.

Onishi, who has been interested in the distribution route of the volcanic rocks for some time, decided in the fall of 1997 to model the canoes exactly after those excavated from Jomon ruins in Chiba Prefecture.

The group completed one of the canoes last summer and the robust vehicle passed a buoyancy test on the Sagami River.

Onishi and his group will use the completed 4-meter-long canoe and a another 7-meter-long canoe, which is just about finished, to create catamaran, group members said.

They also made more than a dozen oars by hand, using wood like oak, zelkova and cedar. The oars will be used by the voyagers to propel the catamaran.

At the end of last year, Onishi felled three hemlock trees—each about 25 meters in height and some 85 centimeters in diameter—at the foot of Gumma Prefecture's Mount Akagi.

He then carried the trees into the workshop of Kashira Ifukube, 29, a potter and forest researcher who hails from Atsugi, Kanagawa Prefecture, and started to build the canoes with the help of other group members using stone axes and iron adzes they had also made by hand.

Dugout canoes are not known for their creature comforts, so the group members hope that it will be a fine and calm day in mid-July when Onishi and his fellow sailors set sail on the approximately 16-hour journey to Kozu Island.

Prior to their voyage, the group's members will test the safety and navigational abilities of their vessel in a three-kilometer stretch between the coast of Chigasaki, Kanagawa Prefecture, and an offshore rock called Eboshi-iwa.

We are not free of anxiety, but we hope we will manage to make it to the end, Ifukube said.

If their spirits are not too dampened during their outward-bound journey, the group hopes to use the catamaran to make the return journey as well.