CONTINENTAL NOTES — FRANCE. 55 



larch in its natural habitat in the Alps, that is, between 5300 and 

 7800 feet. The growth is very slow but the timber is magnificent, 

 and of extreme durability, even though the tree may be stag- 

 headed. It grows there mostly pure, though sometimes mixed 

 with various pines. When pure, the young crop should not be 

 allowed to remain too long close grown. At those altitudes the 

 species can do well on all aspects provided there is sufficient 

 depth of soil, or even sufficient fissures in the underlying rock 

 for the tap-root. In point of fact, the tree appears to prefer the 

 cold aspects N. and E., but M. BufFault declares that this is only 

 due to the fact that on the other aspects agriculture and pasture 

 interfered more with the growth of the trees. Such observations, 

 however, may be quite misleading for our own lower altitudes, 

 where different factors intervene. 



12. Turning now to subterranean waters, under forest and 

 outside forest, we may recall the work of Ototsky and Henry, 

 who took careful measurements for long periods of the water- 

 level at far distant points, two in France and two in Russia, and 

 invariably found that the subsoil water-level was markedly 

 lower inside the forest than outside, even close outside. Similar 

 observations have now been made in the Bombay Presidency by 

 Mr R. Pearson, of the Indian Forest Service, and his results are 

 similar, only far more marked. He has shown also that the 

 presence of forest makes the movements of the water-level very 

 much more gradual than they are outside the forest, and that 

 in spite of a heavy rainfall the maximum height of water 

 level does not occur under forests for months after the cessation 

 of the monsoon. It will be remembered that in India the rainy 

 periods are very definite. M, Henry, considering the data given 

 by Mr Pearson (in the February, 1907, number of the Indian 

 Forester), remarks that two-thirds of the rain layer were taken up 

 by the forest before reaching the subsoil, as much by evaporation 

 from the surface of the leaves as by transpiration through the 

 leaves, and by the imbibition of the soil covering and the upper 

 soil layers. The quantity of the water thus returned by the forest 

 to the atmosphere to fall elsewhere — upon crops for example — is 

 simply prodigious. We have thus apparently reached a definite 

 stage in our knowledge of the interaction of forests and waters. 



