. Impressions de la foresterie européenne : lettres écrites pendant six mois d'une visite en Angleterre et sur le continent . Les forêts et la foresterie. devrait être divisé entre ces deux méthodes d'approche, mais elle a maintenant assez généralement reconnu que, bien que les deux sont importantes, la chose la plus efficace pour de est d'arrêter le problème à sa source, plutôt que de s'appuyer autant sur les ouvrages de génie civil plus bas, qui après tout sont alleviative plutôt que préventives. Peut-être la chose la plus importante à propos de tout ce travail est, cependant, qu'il est maintenant reconnu un flux donné doit être trea

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. Impressions of European forestry : letters written during a six months' visit to England and to the continent . Forests and forestry. should be divided between these two methods of approach, but it has now pretty generally come to be recognized that while both are im- portant, the most effective thing to de is to stop the trouble at its source, rather than to rely so much on engineering works lower down, which after all are alleviative rather than preventive in character. Perhaps the most significant thing about all this work is, however, that it is now recognized a given stream must be treated as a unit, from its highest source way up on the mountain sides down to the point where it joins a large river in one of the broad and gently sloping valleys of the plains. EXAMPLES OF STREAM CONTROL WORK Perhaps as interesting examples of the control of torrential streams through engi- neering works as can be found anywhere in as near as 100 feet. On less abrupt gradients the dams are farther apart though still num- erous. The length of the stream bed that must be so treated often runs up to several miles. It will thus be seen that the construc- tion of dams, or barrages, is an expensive pro- cedure, even with the lower prices for labor that obtained before the war. But this is not all. In the case of the worst torrents the streams have to be walled in, wing dams constructed to deflect the over- flow in times of unusual freshets, and in some instances the entire bed of the stream between its retaining walls, has to be substantially paved with stone blocks to withstand the ero- sive pounding of the rocks and other waste that is carried along by the rushing waters. A typical stream is the torrent of Saint Julien in this valley. Up to 1913 over $129, - 000 had been expended on engineering and tree planting work in connection with its. Prance are to be seen in the valley of Saint Jean de Maurienne, east of Chambery, in the Department of Savoie. It is through this valley that on

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