Ishi-bocho (a ground stone tools excavated from remains in the Jomon and Yayoi periods in Japan) (石包丁)

The term ishi-bocho (stone implement) refers to a ground stone tool excavated from remains in the Jomon period or Yayoi period in Japan (in Yangshao culture and Longshan culture in China). The ishi-bocho is believed to follow the spread of rice cropping and to become popular in its early stage.

This ground stone (smooth surface stone tool to be achieved by rubbing stones each other) is in a thin board-like form with the length of 12 to 20 centimeters, and the width of 3 to 5 centimeters; it is just the size of the palm of the hand and its shape is rectangular or semicircular. Frequently excavated stone tools are as follows: One side of the stone is like a knife, and one or two holes are made on the side of stone to put the thread through so that people hang it on the finger or put it around the hand to prevent it from dropping. Some of excavated ishi-bocho was chipped stone tools, showing that the culture in those days was not uniformity spread.

Although ishi-bocho means a knife made of stone in Japanese, it was not used for the cooking of fish, meat and vegetable, and it is believed that the tool was used to cut off the rice ear from rice in the time of rice harvesting. This belief is based on the fact that the remains peculiar to rice were found in the blade area of the excavated ishi-bocho in the past, while the remains of plants and animals that were thought to be ate at that time were not found.

The name ishi-bocho derived from researchers in the Meiji period who called it the name because ishi-bocho resembled the cooking knife used by Northern Native Americans in shape, and afterwards the name became common; it seems that ishi-bocho was believed to be cookware at first. Ishi-bocho was not unusual as stone tool, and it is excavated in many of the ancient structural remnants where people resided permanently with the advance of agricultural culture in Japan.

Although knives and sickles today are equipped with handle for the purpose of protecting hands and improving work efficiency, ishi-bocho was not equipped with handle. It is considered that because only the part of rice ear was plucked off. Although rice today grow ripe almost simultaneously due to the cultivating technology and breed improvement, rice in those days grew almost naturally in marshland, and harvesting time varied widely according to the kind of rice even at the same place and period; therefore, it is imagined that people in those days selected the rice ears suitable for harvesting, and reaped them only.

Because ishi-bocho was able to be made of materials that were found everywhere comparatively, it was used widely in the early stage of rice cultivation culture; however, later on as bronze ware or ironware that permitted various processes with firmness and sharpness spread, it began to be obsolete. It was observed that transitionally stone tools were used together with precious and expensive bronze wares and others at the same time and in neighboring areas.

Meanwhile wooden farming equipment (wooden rice ear cutting tool) that was used for the same application was also found, but the test in Nishinomiya City Folk Museum showed that when wooden rice ear cutting tool like ishi-bocho was used, work efficiency was reduced by only several times of harvesting.

[Original Japanese]