The following is the probable supply of Larch timber from Athol, beginning twelve years from 1817. The Larch is unquestionably the most enduring timber that we have. It is remarkable, that whilst the red wood or heart wood is not formed at all in the other resinous trees, till they have lived for a good many years, the Larch, on the contrary, begins to make it soon after it is planted; and while you may fell a Scotch fir of thirty years old, and find no red wood in it, you can hardly cut down a young Larch large enough to be a walking stick, without finding just such a proportion of red wood compared to its diameter as a tree, as you will find in the largest Larch tree in the forest, compared to its diameter. To prove the value of the Larch as a timber tree, several experiments were made in the river Thames. Posts of equal thickness and strength, some of Larch and others of oak, were driven down facing the river wall, where they were alternately covered with water by the effect of the tide, and then left dry by its fall. This species of alternation is the most trying of all circumstances for the endurance of timber; and accordingly the oaken posts decayed, and were twice renewed in the course of a very few years, while those that were made of the Larch remained altogether unchanged.
