抄録
1) Durability of “Hiba” wood is considered to be due to its alcohol-benzene soluble constituents, which is probably ethereal oil.
2) Durability of “Kuri” wood is considered to be attributed to its hotwater soluble constituents.
3) “Momi” wood and “Buna” wood have no toxic matter either in their hotwater soluble or in their alcohol-benzene soluble constituents.
