ALBERT R. MANN LIBRARY New York STATE COLLEGES OF AGRICULTURE AND HOME ECONOMICS AT CORNELL UNIVERSITY Cornell University Library SD 409.B87R 1880 “Mic or, Records of the Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924002980542 INTERNATIONAL FORESTRY EXHIBITION. WORKS ON FOREST SCIENCE. By rae REV. J. ©, BROWN, LL.D. 0 Epmvsurcu : OLIVER & BOYD. Lowpon : SIMPKIN, MARSHALL, & CO., anp W. RIDER & SON. Montrea,: DAWSON, BROTHERS. a v I.—Introcuction to the Study of Modern Forest Hconomy. Price 5s. In this there are brought under consideration the exten- sive destruction of forests which has taken place in Europe and elsewhere, with notices of disastrous consequences which have followed—diminished supply of timber and firewood, droughts, floods, landslips, and sand-drifts—and notices of the appliances of Modern Forest Science success- fully to counteract these evils by conservation, planting, and improved exploitation, under scientific administration and management, ExrTrRact FROM Prerace,—‘ At a meeting held on the 28th of March last year (1883), presided over by the Marquis of Lothian, while the assemblage was representative of all interests—scientific, practical, and professional—it was resolved :—‘‘ That it is expedient in the interests of torestry, and to promote a movement for the establishment of a National School of Forestry in Scotland, as well as with a view of furthering and stimulating a greater improvement in the scientific management of woods in Scotland and the sister countries which has manifested itself during recent years, that there should be held in Edin- burgh, during 1884, and at such season of the year as may be arranged, an International Exhibition of forest products and other objects of interest connected with forestry.” It was then moved, seconded, and agreed :—‘‘ That this meeting pledges itself to give its hearty co-opera- tion and patronage to the promotion of an International Forestry Exhibi- tion in Edinburgh in 1884; and those present resolve to give their best efforts and endeavours to render the Exhibition a success, and of such importance and general interest as to make it worthy of the name of International.” ‘It isin accordance with this resolution, and in discharge of obligations which it imposed, that this volume has been prepared.’ 2 II.—_The Forests of England; and the Management of them in Bye-gone Times. Price 6s. Ancient forests, chases, parks, warrens, and woods, are described ; details are given of destructive treatment to which they have been subjected, and of legislation and literature relating to them previous to the present century. Exrract From Prerace.—‘ Contrast with this [the paucity of works in English on Forest Science], the richness of Continental languages in literature on such subjects. I have had sent to me lately Ofversight of Svenska Skogsliteraturen, Bibliografiska Studicren of Axel Cnattingius, a list of many books and papers on Forest Science published in Sweden ; I have also had sent to me a work by Don José Jordana y Morera, Ingenero de Montes, under the title of Apuntes Bibliographico Forestale, a catalogue raisonné of 1126 printed books, MSS., &c., in Spanish, on subjects connected with Forest Science. ‘Tam at present preparing for the press a report on measures adopted in France, Germany, Hungary, and elsewhere, to arrest and utilise drift- sand by planting them with grasses and trees ; and in Der Huropaeische Flug-sand und Seine Cultur, von Josef Wessely General Domaenen- Inspecktor, und Forst-Academie-Direktor, published in Vienna in 1873, I find a list of upwards of 100 books and papers on that one department of the subject, of which 30, in Hungarian, Latin, and German, were published in Hungary alone. ‘ According to the statement of one gentleman, to whom application was made by a representative of the Government at the Cape, for infor- mation in regard to what suitable works on Forest Economy could be procured from Germany, the works on Forst- Wissencha/t, Forest Science, and Forst- Wirthchaft, Forest Economy, in the German language may be reckoned by cartloads. From what I know of the abundance of works in German, on subjects connected with Forestry, I am not surprised that such a report should have been given. And with the works in German may be reckoned the works in French. ‘In Hermann Schmidt’s Fach Katalogue, published in Prague last year (1876), there were given the titles, &c., of German works in Forst und Jagd-Literatur, published from 1870 to 1875 inclusive, to the 31st of - Getober of the latter year, amounting in all to 650, exclusive of others given in an appendix, containing a selection of the works published prior to 1870. They are classified thus :—General Forest Economy, 93 ; Forest Botany, 60 ; Forest History and Statistics, 50; Forest Legislation and Game Laws, 56; Forest Mathematics, 25 ; Forest Tables and Measurements, &c., 148; Forest Technology, 6; Forest Zoology, 19 ; Peat and Bog Treatment, 14; Forest Calendars, 6; Forest and Game Periodicals, 203 Forest Union and Year Books, 13; Game, 91; Forest and Game in. Bohemian, 44. In all, 652. Upwards of a hundred new works had been published annually. Amongst the works mentioned is avolume entitled Die Literatur der letzten sieben Jahre (1862-1872) aus 3 dem Gesammigebiete der Land-und Forst-wirthschaft mit Einschluss der landw. Geweber u. der Jagd, in deutscher, franzdsischer u englisher Sprache Herausg. v. d. Buchandl, v. Gerold and Co., in Wein, 1878, a valuable catalogue filling 278 pages in large octavo. ‘ This volume is published as a small contribution to the literature of Britain, on subjects pertaining to Forest Science. ‘It is after due consideration that the form given to the work—that of a compilation of what has been stated in works previously published —has been adopted. III.—Forestry of Norway. Price 5s. There are described in successive chapters the general features of the country. Details are given of the geo- graphical distribution of forest trees, followed by discussions of conditions by which this has been determined—heat, moisture, soil, and exposure. The effects of glacial action on the contour of the country are noticed, with accounts of existing glaciers aud snow-fields, And information is supplied in regard to forest exploitation and the transport of timber, in regard to the export timber trade, to public instruction in sylviculture, and to forest administration, and to ship-building and shipping. Extract FrroM Prerace.—‘In the spring of 1877, while measures were being taken for the formation of an Arboretum in Edinburgh, I issued a pamplet entitled The Schools of Forestry in Hurope: a Plea for the Creation of a School of Forestry in connection with the Arboretum in Edinburgh. After it was made known that arrangements were being carried out for the formation of an International Exhibition of forest roducts, and other objects of interest connected with forestry, in Edin- Etceh with a view to promoting the movement for the establishment of a National School of Forestry in Scotland, and with a view of furthering and stimulating a greater improvement in the scientific management of woods in Scotland, and the sister countries, which has manifested itself during recent years, the council of the Kast Lothian Naturalists’ Club resolved on having a course of lectures or popular readings on some subject connected with forestry, which might enable the members and others better to profit by visits to the projected Exhibi- tion, and which should be open to the public at a moderate charge, The conducting of these was devolved upon me, who happened to be vice- president of the club. The following treatise was compiled from information then in my possession, or within my reach, and it constituted the basis of these lectures.’ 4 IV.—Finland: its Forests and Forest Management. Price 6s 6d. In this volume is supplied information in regard to the lakes and rivers of Finland, known as The Land of a Thousand Lakes, and as The Last-born Daughter of the Sea ; in regard to its physical geography, including notices of the contour of the country, its geological formations and indications of glacial action, its flora, fauna, and climate; and in regard to its forest economy, embracing a discussion of the advantages and disadvantages of Svedjande, the Sartage of France, and the Koomaree of India; and details of the development of Modern - Forest Economy in Finland, with notices of its School of Fores- try, of its forests and forest trees, of the disposal of its forest. products, and of its legislation and literature in forestry are given. Extract rrom Prerace.—‘I happened to spend the summer of 1879 in St. Petersburg, ministering in the British and American Chapel in that city, while the pastor sought relaxation for a few months at home. I was for years the minister of the congregation worshipping there, and I had subsequently repeatedly spent the summer among them in similar circumstances. I was at the time studying the Forestry of Europe ; and I availed myself of opportunities afforded by my journey thither through Norway, Sweden, and Finland, by my stay in Russia, and by my return through Germany and France, to collect information bearing upon the enquiries in which I was engaged. On my return to Scotland Icontributed to the Journal of Forestry a series of papers which were afterwards reprinted under the title Glances at the Forests of Northern Hurope. In the preface to this pamphlet I stated that in Denmark may be studied the remains of forests in pre-historic times; in Norway, luxuriant forests managed by each proprietor as seemeth good in his own eyes; in Sweden, sustained systematic endeavours to regulate the management of forests in accordance with the latest deliverances of modern science; in Finland, Sartage disappearing before the most advanced forest economy of the day; and in Russia, Jardinage in the north, merging into more scientific management in Central Russia, and Aéboisement in the south. This volume is a study of information which T then collected, together with information which I previously possessed, or have subsequently obtained, in regard to the Forests and Forestry of Finland.’ i Translation of Extracts from Letters from Dr A. Bromevist, Director of the Finnish National School of Forestry at Evois :—‘On my return from Salmos three weeks ago I had the great pleasure to receive your volume on the Forests and Forest Management in Finland. I return 5 you grateful thanks for the gift, and no less for publishing a description of the forestal condition of our country. It is with sentiments of true gratitude I learn that you had previously taken part in a work so important to our country as the preparation of a new edition of the New Testament in Finnish. Your descriptions of our natural scenery are most excellent and interestivg. Personally I feel most interest in your accounts of Koomaree. I value it much. and not less so your concurrent final conclusion in regard to the effects of the exercise of it in Finland,’ Translation of Statement by M, Dz La Gryvz, in the Revue des Laux et Férets of January 1884 :—‘In an address delivered some weeks since at a banquet of exhibitors in the French section at Amsterdam, M. Herisson, Minister of Commerce, expressed an intention to publish a series of small books designed to make known to French merchants foreign lands in a commercial point of view. If the Minister of Commerce wishes to show to our merchants the resources possessed by Finland, he need not go far to seek information which may be useful to them, they will be found in « small volume which has just been published by Mr John Croumbie Brown. ‘ Mr Brown is one of those English ministers, who, travelling over the world in all directions [some at their own cost], seeking to spread the Word of the Lord in the form of Bibles translated into all languages, know how to utilise the leisure left to them at times while prosecuting this mission. Some occupy themselves with physical science, others with archeology, some with philology, many with commerce ; Mr Brown has made a special study of sylviculture. He has already published on this subject many works, from amongst which we may cite these : Hydrology of South Africa ; The Forests of England ; The Schools of Forestry in Hurope ; Réboisement in France; Pine Plantations on Sand Wastes in France. ‘His last book on Finland is the fruit of many journeys made in that country, which he visited for the first time in 1833, but whither he has returned frequently since that time. Mr Brown gives narratives of his voyages on the lakes which abound in Finland, and his excursions in the immense forests, the exploitation of which constitutes the principal industry of the country. The School of Forestry at Evois has furnished to him much precise information in regard to the organisation of the service, and the legislation and the statistics of forests, which, added to what he had procured by his own observation, has enabled him to make a very complete study of this country, poetically designated The Land of a Thousand Lakes, and which might also justly be called The Kingdom of the Forest, for there this reigns sovereign.’ V.—Forest Lands and Forestry of Northern Russia. Price 6s 6d. Details are given of a trip from St. Petersburg to the forests around Petrozavodsk on Lake Onega, in the government of Qlonetz; a description of the forests 6 on that government by Mr Judrae, a forest official of high position, and of the forests of Archangel by Mr Hepworth Dixon, of Lapland, of the land of the Samoides and of Nova Zembla; of the exploitation of the forests by Jardinage, and of the evils of such exploitation; and of the export timber trade, and disposal of forest products. In connection with discussions of the physical geography of the region information is supplied in regard to the contour and general appearance of the country ; its flora, its forests, and the palaeontological botany of the regions beyond, as viewed by Professor Heer and Count Saporta ; its fauna, with notices of game, and with copious lists of coleoptera and lepidoptera, by Forst-Meister Gunther, of Petrozavodsk. Extract From Prerace.—‘In the spring of 1877 I published « brochure entitled The Schools of Forestry in Europe: a Flea for the Crea- tion of a School of Forestry in connection with the Arboretum in Edin- burgh, iu which with details of the arrangements made for instruction in Forest Science in Schools of Forestry in Prussia, Saxony, Hanover, Hesse, Darmstadt, Wurtemburg, Bavaria, Austria, Poland, Russia, Finland, Sweden, France, Italy, and in Spain, and details of arrange- ments existing in Edinburgh for instruction in most of the subjects in- cluded amongst preliminary studies, I submitted for consideration the opinion, ‘‘that with the acquisition of this Arboretum, and with the ex- isting arrangements for study in the University of Edinburgh, and in the Watt Institution and School of Arts, there are required only facil'- ties for the study of what is known on the Continent as Forest Science to enable these Institutions conjointly, or any one of them, with the help of the other, to take a place amongst the most completely equipped Schools of Forestry in Europe, and to undertake the training of foresters for the discharge of such duties as are now required of them in India, in our Colonies, and at home.” ‘This year has seen world-wide arrangements for an International Exhibition of forest products and other objects of interest connected with forestry in Edinburgh, *‘In the interests of forestry, and to pro- mote a movement for the establishment of a School of Forestry in Scot- land, as well as with a view of furthering and stimulating a greater im- provement in the scientific management of woods in Scotland and the sister countries which has manifested itself during recent years.” _ ‘The following is one of a series of volumes published with a view to introduce into English forestal literature detailed information on some of the points on which information is supplied to students at Schools of Forestry on the Continent ; and to make better known the breadth of study which is embraced in what is known there as Forstwissenscaft, or Forest Science,’ , 7 VI.—French Forest Ordinance of 1669; with Historical Sketch of Previous Treatment of Forests in France. Price 4s. The early history of forests in France is given, with de- tails of devastations of these going on in the first half of the seventeenth century; with a translation of the Ordi- nance of 1669, which is the basis of modern forest econo- my; and notices of forest exploitation in Jardinage, in La Methode a Tire et Aire, and in La Methode des Comparti- ments, Extract FRoM Prerace.—‘ “ The Celebrated Forest Ordinance of 1669: Such is the character and designation generally given at the present day to the Ordinance in question. It is known, by reputation at least, in every country on the Continent of Europe; but, so far as is known to me, it hasnever before been published in English dress. It may possibly be considered antiquated ; but, on its first promulgation, it was welcomed, far beyond the bounds of France, as bringing lite to the dead ; and I know of no modern system of Forest Exploitation, based on modern Forest Science, in which I cannot trace its influence. In the most advanced of these—that for which we are indebted to Hartig and Cotta of Saxony—I see a development of it like to the development of the butterfly from what may be seen in the structure of the chrysalis ; and thus am I encouraged to hope that it may prove suggestive of bene- ficial arrangements, even where it does not detail what it may be deemed desirable to adopt. ‘In my translation I have followed an edition issued with Royal ap- proval in 1753, with one verbal alteration to bring it into accordance with certain older approved editions, and with another verbal alteration to bring it into accordance with editions issued in 1699, 1723, 1734, and 1747.” Translation of notice by M. De La Gre for July 1883 in the Revue des Haux et Férets: ‘England, which with her immense possessions in India, in Canada, and in the Cape of Good Hope, is beyond all question a State rich in forests, has never up to the present time given to this ortion of her domains more than a very moderate share of her attention ; Bit for some years past public opinion is becoming alarmed, in view of the immense devastations which have been committed in them, and the forest question coming forward spontaneously has hecome the subject of numerous publications : amongst which, atter the excellent monthly collection, the Journal of Forestry and Estate Management, comes the Translation of the Ordinance of 1669, which has just been published by Mr John Croumbie Brown. ‘This translation of a monument of juris- prudence, well known in France, but which has never before been repro- duced in English, has furnished to Mr Brown an opportunity of giving a historical sketch of French Forest Legislation, and an exposition of the 8 different methods of exploitation followed in our country. Drawn from the best sources, and commented on with talent, these documents form an elegant volume, which the author has made the more complete by binding with it a summary of the treatise he has published on the Forests of England.’ VII. —Pine Plantations on Sand Wastes in France. Price ‘7s. In this are detailed the appearances presented by the Landes of the Gironde before and after culture, and the Landes of La Sologne; the legislation and literature of France in regard to the planting of the Landes with trees ; the characteristics of the sand wastes; the natural his- tory, culture, and exploitation of the maritime pine, and of the Scots fir; and the diseases and injurious influences to which the maritime pine is subject. Extracts FRoM Prerace.—‘ The preparation of this volume for the press was undertaken in consequence of a statement in the Standard and Maik, a Capetown paper, of the 22d July 1876, to the effect. that in the estimates submitted to Parliament £1000 had been put down for the Cape Flats, it was supposed with a view to its being employed in car- rying out planting operations as a means of reclaiming the sandy tracts beyond Salt River. ‘This volume was originally compiled in view of what seemed to he required at the Cape of Good Hope, It has been revised and printed now, as a contribution towards a renewed enterprise to arrest and utilise eand-wastes which stretch from Table Mountain to the Hottentot Holland Mountains; and additional information is forthcoming if it should be desired.’ VIII.—Reboisement in France; or, Records of the Re- planting of the Alps, the Cevennes, and the Pyrenees, with Trees, Herbage, and Bush, with a view to arresting and preventing the de- structive consequences of torrents. Price 12s. In this are given a résume of Surell’s study of Alpine torrents, of the literature of France relative to Alpine tor- rents, and of remedial measures which have been proposed for adoption to prevent the disastrous consequences fol- 9 lowing from them—translations of documents and enact- ments, showing what legislative and executive measures have been taken by the Government of France in connec- tion with réboisement as a remedial application against destructive torrents—and details in regard to the past, present, and prospective aspects of the work. Extract From Prerace.—‘ In a treatise on the Hydrology of South Africa I have given details of destructive effects of torrential floods at the Cape of Good Hope and Natal, and referred to the measures adopted in France to prevent the occurreuce of similar disastrous floods there. The attention of the Legislative Assembly at the Cape of Good Hope was, last year, called by one of the members of the Assembly to the importance of planting trees on unproductive Crown lands. On learn- ing that this had been done I addressed to the editor of the Cape Argus a communication, of which the following is a copy :— ‘“T have before me details of destructive effects of torrents which have occurred since I left the Colony in the beginning of 1867. Towards the close of that year there occurred one, the damage occasioned by which to roads and to house property at Port Elizabeth alone was estimated at from £25,000 to £30,000. Within a year thereafter a similar destructive torrent occurred at Natal, in regard to which it was stated that the damage done to public works alone was estimated at £50,000, while the loss to private persons was estimated variously from £50,000 to £100,000. In the following year, 1869, a torrent in the Western Province occa- sioned the fall of a railway bridge, which issued in loss of life and loss of property, and personal injuries, for one case alone of which the rail- way proprietors were prosecuted for damages amounting to £5000. In Beaufort West a deluge of rain washed down the dam, and the next year the town was flooded by the waters of the Gamko; and the next year, 1871, Victoria West was visited with a similar disaster. Such are the sums and the damages with which we have to deal in connection with this question, as it affects the case; and these are only the most remarkable torrents of the several years referred to. I have spoken of millions of francs being speat on réboisement in France, and some may be ready to cry out, ‘ Nothing like such an expenditure can be under- taken at the Cape!’ Perhaps not; but the losses occasioned by the torrents seem to amount at present to about a million of francs in the year, This falls in a great measure on individuals, that would fall on the community ; and the community in return would benefit by water rétained to fertilize the earth, instead of being lost in the sea, and by firewood and timber being grown where now there is none. These are facts well deserving of consideration in the discussion of the expediency of planting Crown lands with trees.” ‘Towards the close of last year, 1874, still more disastrous effects were produced by torrential floods, According to the report given by one of the Colonial newspapers, the damages done could not be esti- mated at much less than £300,000. According to the report given by 10 another, the damage done to public works alone was estimated at £350,000,—eight millions, seven hundred and fifty thousand francs. And my attention was called anew to the subject. “On addressing myself to M. Faré, Director-General of the Administra- tion of Forests in France, there was afforded to me every facility I could desire for extending and verifying the information I had previously col- lected in regard to the works of réboisement to which I have referred. Copies of additional documents were supplied to me, with copies of works sanctioned by the Administration, and arrangements were made for my visiting and inspecting, with every assistance required, the works begun and the works completed ; and thus I have been enabled to sub- mit a much more complete report than it would otherwise have been in my power to produce, ‘While the compilation I have prepared owes its publication at this time to the occurrence of the inundations of last year at the Cape of Good Hope, the publication has been undertaken in the hope that in other countries besides South Africa the information may be turned to practical account.’ Translation of extract from letter to the author by M. ALEXANDRE SuRELL, Jngenieur des Ponts et Chausses, chairman of the Compagnie des Chemins des Fer du Midi et du Canal lateral a la Garonne, and author of Kitude sur les Torrents des Hautes-Alps, Ouvrage Couronne par ? Academie des Sciences en 1842 :—‘ You are rendering an eminent service to society in calling the attention of serious thinkers to the subject of réboisements and gazonnements. It is a vital question affecting our descendants, specially in southern climates, there are useful truths which have to be diffused there, and you have fulfilled this duty amongst your country- men, , ‘In France public opinion, long indifferent, is now sufficiently en- lightened on the question, and much has been done. ‘I have been able to establish in the course of a recent journey that, throughout a great part of Switzerland, in Styria, in Carinthia, and in the Tyrol, the same phenomena which have issued in the desola- tion of our French Alps are beginning to produce the same effects. There have been recognised a number of extinct torrents which had originated in the destruction of the forests. If people go on sleeping, and the administration or the communes do nothing to arrest the evil, posterity will have a sad inheritance devolved upon it. : ‘You have given, with very great clearness, a résumé of what I have done in France, be it by my works, or be it by my workings, for the re- generation of our mountains,’ Translation of extract from letter by the late M. Ernest Cézanne, Jn- genicur des Ponts et Chausses, Représentant des Hautes Alpes a ? Assemblée Nationale, and author of Une Suite to the work of M. Surell. ‘ The post brought to me yesterday your very interesting volume on Réboise- ment. Lat once betook myself to the perusal of it ; and I am surprised that a foreigner could digest so completely such a collection of our French documents drawn from so many diverse sources, The problem 11 of réboisement and the regeneration of the mountains is one of the most in- teresting which man has to solve, but it requires time and money, and with the authorities and political assemblies, technical knowledge which is as yet but very sparingly possessed. It is by books so substantial as yours, sir, that public opinion can be prepared to face the importance of this great work.’ IX.—Hydrology of South Africa; or Details of the Former Hydrographic Condition of Cape of Good Hope, and of Causes of its Present Aridity, with Suggestions of Appropriate Remedies for this Aridity. Price 10s. In this the desiccation of South Africa, from pre-Adamic times to the present day, is traced by indications supplied by geological formations, by the physical geography or the general contour of the country, and by arborescent pro- ductions in the interior, with results confirmatory of the opinion that the appropriate remedies are irrigation, arboriculture, and an improved forest economy: or the erection of dams to prevent the escape of a portion of the rainfall to the sea—the abandonment or restriction of the burning of the herbage and bush in connection with pastoral and agricultural operations—the conservation and extension of existing forests —and the adoption of measures similar to the réborsement and gazonnement carried out in France, with a view to prevent the formation of torrents, and the destruction of property occasioned by them. M. Jules Clavé, of world-wide reputation as a student of Forest Science, wrote in the Revue des Deux Mondes of Ist May 1882 :— [Translated.] ‘Since the first travels of Livingstone, the African continent, hitherto inacessible, has been attacked on all points at once. By the north, and by the south, by the east, and by the west, hardy explorers have penetrated it, traversed it, and have dragged from it some of its secrets, ‘[ravellers have paid tribute and done their work in opening up a path; it is now for science and civilisation to do theirs, in studying the problems which present themselves for investigation ; and in drawing in the current of general circulations the peoples and lands, which appear as if destined to stand outside; and in causing ta 12 contribute to the increase of social wealth the elements of production previously unknown. Thus are we led to receive with interest works which can throw a new light on the condition of regions which may have been known fora long time, and which make known the conditions oftheir prosperity. It is under this title that the work of the Rev. J. C. Brown on the Hydrology of South Africa appears deserving of notice ; but it is so also from other points of view. Mr Brown, after a previous residence in the colony of the Cape, whither he had been sent in 1844 as a missionary and head of a religious congregation, returned thither in 1863 as Professor of Botany in the College of South Africa, and he remained there some years. In both of these positions he had occasion to travel through the colony in all directions, and had opportunities to col- Ject most valuable information in regard to its physical geography. Mr Brown on going out to the Cape knew nothing of the works which had for their object to determine the influence of forests on the climate, on the quantity of rain, and on the river-courses in Europe ; he had never heard mention of the work of M. Surell on the torrents of the Alps, or of that of M. Mathieu on forest meteorology, nor of those of M. Domontzey, Costa de Bastelica, and so many others on the subject of réboisement ; and yet in studying by himself, and without bias, the climatic condition of South Africa, he came to perceive that the dis- turbances in the regularity of the flow of rivers within the historic period should be attributed in a large measure to the destruction of forests ; and he meets in agreement on this point the savants whose names have been mentioned, We have thought it might not be with- out interest to readers of the Revue to have in the lines of Mr Brown a collection of phenomena which, in their manifestation at any speci- fied point are not less due to general causes, the effects of which may be to make themselves felt everywhere where there may be existent the same conditions than to aught else.’ And there follows a lengthened article in illustration. X.—Water Supply of South Africa, and Facilities for the Storage of it. Price 18s 6d. In this volume are detailed meteorological observations on the humidity of the air and the rainfail, on clouds, and winds, and thunder-storms; sources from which is derived the supply of moisture which is at present available for agricultural operations in the Colony of the Cape of Good Hope and regions beyond, embracing the atmosphere, the rainfall, rivers, fountains, subterranean streams and reser- voirs, and the sea; and the supply of water and facilities for the storage of it in each of the divisions of the colony 18 —in Basutoland, in the Orange River Free State, in Griqualand West, in the Transvaal Territory, in Zululand, at Natal, and in the Transkei Territory. Extract From Prerace.—‘ Appended to the Report of the Colonial Botanist at the Cape of Good Hope for 1866 was an abstract of a Memoir prepared on the Hydrology of South Africa, which has since been embodied in a volume which has been published on that subject, and an abstract of a Memoir prepared on Irrigation and its application to agricultural operations in South Africa, which embraced a Report on the Water Supply of the Colony ; its sources, its qnantity, the modes of irrigation required in different circumstances, the facilities for the adop- tion of these in different districts, and the difficulties, physical and other, in the way of works of extensive irrigation being carried out there, and the means of accomplishing these which are at command. ‘In the following volume is embodied that portion of the Memoir which related to the water supply, and the existing, facilities for the storage of this, with reports relative to this which were subsequently received, and similar information in regard to lands beyond the Colony of the Cape of Good Hope, which it has been sought to connect with the Colony by federation, or otherwise ; and the information relative to irrigation has been transferred to a Report on the Rivers of the Colovy, and the means of controlling floods, of preventing inundations, of regulating the flow of rivers, and utilising the water by irrigation otherwise. ‘In the series of volumes to which this belongs its place is immedi- ately after that on the Hydrology of South Africa, which contains details of the former hydrographic condition of the Cape of Good Hope, and of causes of its present aridity, with suggestions of appropriate remedies for this aridity ; and it has been prepared to show that, not in a vague and general use of the terms, but in strict accordance with the statement, the severe, protracted, and extensive droughts, and destructive floods and inundations, recorded in the former volume, find their counterpart in constantly alternating droughts and deluges in every district of the Colony,—and that, in every so-called division of it, notwithstanding the deluges, there were protracted sufferings from drought, and, notwithstanding the aridity, there is a supply of water at command, with existing facilities for the storage of the superabundant supply which at present proves productive of more evil than good.’ Statement by Reviewer in Huropean Mail :—‘ Dr Brown is well known at the Cape, for in the exercise of his duties he travelled over the prin- cipal part of it, and much, if not indeed the substance, of the bulky volume before us, has been before the Cape public in the form of Reports to the local Government. As these reports have been commented upon over and over again by the local press there is little left for us to say beyond the fact that the author reiterates his opinion that the only panacea fox the drought is to erect dams and other irrigation works for the storage of water when the rains come down. There can be no doubt 14 that this is sage and wholesome advice, and the only question is, who is to sustain the expense? Not long ago, somewhere about the time that Dr Browa was prosecuting his labours, it will be remembered that General Wynard said that ‘‘ Nature had furnished the cups if only science would take the trouble to make them secure.” It is but to repeat an oft-told story that with a good supply of water South Africa would be une of the finest of nature’s gardens, and would be capable of producing two crops a year, in addition to furnishing fodder for sheep and cattle. The question of the water supply for irrigation and other purposes has been staved off year after year, and nothing has been done. It is not too much to say, however, that the question must make itself felt, as it is one of the chief factors in the ultimate prosperity of South Africa. The author is evidently in love with his subject, and has con- tributed a mass of facts to Hydrology which will be useful to all coun- tries of an arid character.’ XI.—Forests and Moisture; or Effects of Forests on Humidity of Climate. Price 10s. In this are given details of phenomena of vegetation on which the meteorological effects of forests affecting the humidity of climate depend—of the effects of forests on the humidity of the atmosphere, and on the humidity of the ground, on marshes, on the moisture of a wide expanse of country, on the local rainfall, and on rivers—and of the correspondence between the distribution of the rainfall and of forests—the measure of correspondence between the distribution of the rainfall and that of forests—the distri- bution of the rainfall dependent on geographical position, or determined by the contour of a country—the distribution of forests affected by the distribution of the rainfall—and the local effects of forests on the distribution of the rain- fall within the forest district. Extracts FRoM Prerace.—‘ This volume is one of a series. In the first of the series—a volume entitled—published last year, Hydrology of South Africa ; or, Details of the Former H. ydrographic Condition of the Cape of Good Hope and of Causes of its recent Aridity, with Sugges- tions of appropriate Remedies for this Aridity, ‘This volume, on the effects of forests on the humidity of the atmos- phere and the ground, follows supplying illustrations of the reasonable- ness of the suggestion made in regard to the conservation and extension of forests as a subordinate means of arresting and counteracting the deseccation and aridity of the country.’ =e oe 15 Extracts rrom Lerrers to the author from the late Hon. George P. Marsh, Minister of the United states at Rome, and author of The Harth as Modified by Human Action :—‘I am extremely obliged to you for a copy of your Réboisement in France, just received by post. I hope the work may have a wide circulation. . . . Few things are more needed in the economy of our time than the judicious administration of the forest, and your very valuable writings cannot fail to excite a powerful influence in the right direction. . . . ‘I have received your interesting letter of the 5th inst., with the valuable MSS. which accompanied it. I will make excerpts from the latter, and return it to you soon. I hope the very important facts you mention concerning the effect of plantations on the island of Ascension will be duly verified. . . . ‘I put very little faith in old meteorological observations, aad, for that matter, not much in new. So much depends on local circumstances, on the position of instruments, &c.—on station, in short, that it is only on the principle of the tendency of some to balance each other that we can trust to the registers of observers not known to be trained to scientific accuracy. Even in observatories of repute, meteoro- logical instruments are seldom properly hung and guarded from dis- turbing causes. Beyond all, the observations on the absorption of heat and vapour at small distances from the ground show that thermometers are almost always hung too high to be of any value as indicating the temperature of the stratum of the atmosphere in which men live and plants grow, and in most tables, particularly old ones, we have no information as to whether the thermometer was hung five feet or fifty feet from the ground, or whether it was in any way protected from heat radiated from near objects,’ Extract Lerrer from the late Professor Henry, of the Smithsonian Institution, Washington :—‘ The subject of Forest Culture and its in- fluence on rainfall is, just at this time, attracting much attention in the United States. At the last meeting of the American Association for the advancement of science a committee was appointed to memorialise Con- gress with reference to it. Severalof the Western States Governments have enacted laws and offered premiums in regard to it. The United States Agricultural Department has collected statistics bearing on the question, and we have referred your letter to that establishment. ‘The only contribution that the Smithsonian Institution has made to the subject is that of a series of rain-fall tables, comprising all the obser- vations that have been made in regard to the rainfall in the United States since the settlement of the country ; a copy of this we have sent to your address. ‘It may be proper to state that we have commenced a new epoch, and have, since the publication of the tables in question, distributed several hundred rain gauges in addition to those previously used, and to those which have been provided by the Government ia connection with the signal service.’ These notices and remarks are cited as indicative of the importance which is being attached to the subject discussed. 16 Exrract From Lerrer to the author from Lieut.-Col. J. Campbell Walker, Conservator of Forests, Madras, then Conservator-in-Chief of Forests, New Zealand; author of Report on State Forests and Forest Management in Germany and Austria:—‘I am in receipt of yours, along with the notices of your works on Forestry, by book post. I think very highly of the scope of the works, and feel sure that they ae similar works will supply a want much felt by the Indian forest officers, ‘It contains many important data which I should have vainly sought elsewhere, and it will be regarded by all competent judges as a real substantial contribution to a knowledge of the existing surface, and the changes which, from known or unknown causes, that surface is fast undergoing.’ Copies of any of these Works will be sent post-paid to any address within direct Postal communication with Britain, on receipt by Dr Joun C. Brown, Haddingten, of a Post-Office Order for the price. REBOISEMENT IN FRANCE: OR, RECORDS OF THE REPLANTING OF THE ALPS, THE CEVENNES, AND THE PYRENEES WITH TREES, HERBAGE AND BUSH, WITH A VIEW TO ARRESTING AND PREVENTING THE DESTRUCTIVE CONSEQUENCES AND EFFECTS OF TORRENTS. COMPILED BY JOHN CROUMBIE BROWN, LL.D., Formerly Government Botanist at the Cape of Good Hope, and Professor of Botany in the South African College, Capetown, Honorary Vice- President of the African Institute of. Paris, Fellow of the Royal Geographical Society, Fellow of the Linnean Society, de. SECOND ISSUE. LONDON: C, KEGAN PAUL & CO., 1, PATERNOSTER SQUARE. 1880. PREFACE. Tue following treatise owed its origin, and the first issue of it to a desire which I felt to show that it is quite practicable to prevent, or to moderate inundations at the Cape of Good Hope, such as occasionally occur there, destroying property of great value. for some years I held the appoint- ment of Government Botanist in that Colony, and there saw something of the appearance of these inundations, and the serious consequences following. Of both I have given details in a volume, entitled “ Hydrology of South Africa ; or, Details of the former hydrographic condition of the Cape of Good Hope, and of causes of its present aridity, with suggestions of appropriate remedies for this aridity.”* And in the preface to the former issue of this treatise, I had occasion to state—‘I have before me details of destructive effects of torrents which have occurred since I left the Colony in ‘the beginning of 1867. Towards the close of that year there occurred one, the damage occasioned by which to roads and to house property at Port Elizabeth alone was estimated at from £25,000 to £30,000. Within a year thereafter a similar destructive torrent occurred at Natal, in regard to which it was stated that the damage done to public works alone was estimated at £50,000, and the loss to private persons was estimated variously from £50,000 to £100,000. In the following year, 1869, a torrent in the Western Province occasioned the fall of a railway bridge, which issued in loss of life and loss of property, and personal injuries, for one case alone of which the railway proprietors were prosecuted for damages amounting to £5000. In Beaufort West a deluge of rain washed down the dam, and the next year the town was flooded by the waters of the Gamka; and the next year, 1871, Victoria West was visited with a similar disaster. Such are the sums and the damages with which we have to deal in connection with this question, as it affects the case ; and these are only the most remarkable torrents of the several years referred to. “ Towards the close of last year, 1874, still more disastrous effects were produced by torrential floods. According to the report given by one of the Colonial newspapers, the damages done could not be estimated at much less than £300,000. According to the report given by another, the damage done to public works alone was estimated at £350,000,—eight millions, seven hundred and fifty thousand francs. And my attention was called anew to the subject. ; * London: C, Kegan Paul & Co. hy PREFAOH, « Torrents have proved destructive on the continent of Europe by washing away fertile soil, by undermining houses and fields, and whole villages and towns, and causing their fall, by burying fields and vineyards and towns in the debris thus produced, and swept away, and by producing extensive inundations of lower lying level lands, drowning man and beast, and burying, washing away, or otherwise destroying the labour of years, and I would briefly advert to the remedial measures which have been adopted. “ One of the means employed to avert destruction when it was threatened, was the erection on the river-bed of protecting walls, and of advanced structures, to determine the current, and of continuous slopes to regulate its rapidity and force, and of combined and modified forms of all of these appliances, which manifested great art and skill, ingenuity, and power. It would be exaggeration to say they proved in every case an utter failure, but this would only be an exaggeration of what was the fact, which was, that in very many cases they failed to avert the evil, and in not a few cases they were carried away before the torrent like chaff before the wind, while the torrent seemed to laugh a loud and hollow laugh at the silliness of. man’s device. “To prevent the destruction of land by inundations, the more promising measure of raising embankments based or founded on the dry land was adopted, and the river was thus chained within its bed, with only liberty of action within a limited space beyond. But what did the river do? It silted up its-bed, and thus raised itself, and attempted to overflow the embankment. The danger was perceived in time, and the embankments were raised to a higher elevation. The river quietly repeated the silting up of its bed, which was met by a repeated addition to the embankment. This was done again and again. It was a continuous struggle between dead matter and living mind, carried on for years—for generations,—both refusing to give in. Meanwhile, as in the case of the River Po, not only the embankments, but the silted-up bed of the river was elevated consider- ably above the level of the country lying on one side and on the other, an aqueduct of earth overtopping and threatening with destruction houses and trees, and man and beast alike. Then it was a desperate and a deadly struggle, which many saw it would have been well it had never been entered on, while others looked on and said, It is evident that that is not the way in which the evil.is to be averted. Meanwhile the struggle was continued, until a breach was at length effected in the embankment, and the river poured forth its torrent, inundating the country far and wide. “While this contest was going on, the study of torrents in the Alps revealed the form of the bed of these to be a large somewhat semi-circular funnel-shaped basin, from the rainfall in which the waters were collected,— a channel more or less elongated, along which the waters flowed,—and a fan-shaped bed of deposit corresponding to the delta of a river, the whole being like to a river-bed reduced or contracted in length ; it showed, further, that these torrents were to be met with in all stages of progress, from incipient information, throughout various stages of activity, to final extinction ; it showed that in forest-covered mountain regions there were none ; that in denuded mountain ranges they were numerous, and some- times very destructive; that, where they were extinct, the forest had extended itself till it covered the basin and lined the banks of the channel ; that, where they were in a state of progressive extinction, the forests were progressively extending themselves; and that this extension of the forest was apparently the cause or occasion of the extinction of the torrent. PRRFACE. ¥ “ From what had thus been observed the inference was drawn that by artificial plantation the gradual extinction or the subjection of the torrent ‘to control might be effected—and numerous facts which had been long known were recalled to give their testimony in confirmation of the correct- ness of the inference drawn. Rain falling on a metallic roof rushes off, while the same rain falling on a thatched roof trickles down in drops; from the bared ground the rain runs off in streamlets long before it runs off in a similar way from the grass-field or the thicket; and the more the phenomena of percolation and drainage was studied, the more manifest did it become that vegetation retarded the flow and prevented the rush of water, retained it to moisten the soil, and extinguished the torrent, requiring the river to take days and weeks to carry away what the torrent carried away in hours, and thus securing something like a permanent flow in what had become a dry channel, filled occasionally from bank to bank with a destructive torrent, converting the lion into a lamb. And now Millions of francs are being spent on the work of planting trees, and herb- age, ang a with a view to preventing torrents and inundations destroying e land. When the first issue of this volume took place, the inundation which had proved so destructive to Toulouse was engaging the attention of the General Directory of Forests in France, who were satisfied that they had the means of preventing the recurrence of such a catastrophe if they only had the money necessary for carrying out the necessary reboisement and gazonnement of the mountains; and the works have been carried on with more or léss energy ever since. Amongst other important and interesting models exhibited by the Forest Administration at the Exposition Universelle of 1878, were models, and charts, and drawings of works of reboisement of mountains; and in the Budget for 1880, provision has been made for the work being carried out with still increasing energy. An application was made to the Chamber for a credit of about four millions of francs, well nigh £164,000, a million of francs or £111,667 above what had been asked for 1879, for the execution of such works. In making this application the Administration stated that after the disasters occasioned in 1875, by the overflowing of the Garonne and the Herault, and their affluents, the Minister of Finance and the Minister of Public Works gave assurance that measures would be concerted between the departments over which they respectively presided, to be taken with a view to prevent the recurrence of such calamities. They stated that many surveys which were subsequently undertaken had been completed, but in the absence. of funds the works of reboisement had not been begun. That, subsequently the Minister of Public Works had solicited their co-operation to enable him to give a specification of works actually called for in Savoie. That information supplied by the engineers of roads and bridges showed that the four torrents of Saint Martin, the Grillaz, the Pousset, and Saint Julien, all of them afiluents of the Are, were causing every year great destruction, which it was of importance should be arrested without delay. That according to information in possession of the Administration, the execution of the works in Savoié alone would absorb more than a million of francs. The Budget Committee of the Chamber in reporting on the application, submitted a detailed statement of what had been done, and the results, vi PREFACE. giving tabulated statements as well as details, showing how effectually reboisement had arrested torrents, and showing further, that for the comple- tion of the works in the Alps, in the Cevennes, and the plateau of Central France, and in the Pyrenees, there would be required 148 millions of francs, upwards of six millions sterling, and 72 millions more, upwards of three millions sterling, for the purchase of land. And they unanimously recom- mended that a credit for the whole amount applied for should be granted. “We are all,” say they in the concluding sentence of their report, “deeply impressed with the thought—better far spend a million in rebotsement than have to give such a sum to sufferers from inundations.” The credit applied for was unanimously granted by the Chamber, together with a grant made sua sponte of 5000 francs to be employed in developing roads, to facilitate the exploitation of communal forests, the effect of which it was anticipated might .be to raise the average value of 360,000 hectares, or 900,000 acres of forests, from five francs to fifty francs per hectare. And in view of the importance of employing forest engineers of superior attainments in the works of rebovsement in Savoie and in the basin of the Garonne, 50,600 francs, about £2,110, in addition to the credit for the material work was granted. If such sums tell of the great expense at which these works are being executed, they tell of the importance attached to the execution of them, and of the perfect confidence which is felt in their immediate efficiency, and in their ultimately proving remunerative of the outlay. I have retained the terms reboisement and gazonnement, because I know of no equivalent English terms by which they can be replaced. Both in India and in America the former term at least has been adopted ; and I believe it will soon be naturalised among the English speaking population on both sides of the Atlantic. JOHN C. BROWN. Happinaton, 10th December, 1879. PREFACE. In a treatise on the Hydrology of South Africa I have given details of destructive effects of torrential floods at the Cape of Good Hope and Natal, and referred to the measures adopted in France to prevent the occurrence of similar disastrous floods there. The attention of the Legislative Assembly at the Cape of Good Hope was, last year, called by one ‘of the members of the Assembly to the importance of planting trees on unproductive Crown lands. On learning that this had been done I addressed to the editor of the Cape Argus a communication, of which the following is a copy :— My last communication shows, I consider, no lack of interest on my part in whatever may tend to secure the conservation and improved management of the forests of the Colony ; but important as I consider the fact that attention is being given by the Legislature to a suggestion by the Conservator of forests at the Zitzikamma, having this for its object, 1 attach still more importance to the faet that attention is being called in the Legislative Assembly to the question of the expediency of planting Crown lands with trees. In several other countries the same work has been begun ; and the evils against one or more of which they are seeking in these countries to protect themselves by planting trees by the million, are all of them already to be met with at the Cape, and many of them are to be met with there at the same time and in the same place, all mustering in full force, while elsewhere in many cases it is only the anticipation and dread of some one or other of them, or the partial prevalence of them, which has prompted to the precautionary measure. At the Cape, through- out extensive districts, we meet with want of fuel, multitudes being driven to the use of mist in cooking food, and multitudes more numerous being unable to obtain even this; winds powerful, if not terrific, sweep over the land, with hail and tempest ; droughts, long-continued droughts, alternate with deluges of rain and’ thunderstorms ; heat by day in some districts is succeeded not unfrequently by frosty nights ; locusts and voetyangers remind one of what is written of Judea, “‘ That which the palmerworm hath left hath the locust eaten, and that which the locust hath left hath the cankerworm eaten, and that which the cankerworm hath left hath the caterpillar eaten ;” and then, when it is least expected—the sky unclouded, the sun or the moon shining in its brightness,—down comes a river, carrying all before its wave. : A il PREFACE. These are evils, the dread of one or other, or of some combination of which, is prompting many elsewhere to labour like men chained to the pumps of a vessel foundering at sea, in the hope that they may yet avert what they fear; and the measures adopted by them are similar to those to which reference has been made. My ears still ring with the echoes of Reboisement, and the corresponding terms applied to the operation of planting or replanting forests where they have been destroyed ; and I cannot but hope that the means thus employed, if adequate to avert the dreaded evil, might prove to some extent an appropriate remedy for the evil where it exists. I say nothing at present of what may have brought about the present state of things. I admit the importance of the consideration of this in discussing in full the subject ; but it is enough for me, and it will probably be deemed enough by many of your readers, that I am satisfied J am giving safe advice in saying,—Look to what men are doing elsewhere! Wishing to give unity and completeness to my communication, I shall at present refer only to what is being done to bridle torrents by planting trees, knowing that the torrents of the Colony have been destructive both of life and property to avery great extent, and that almost every year has its doleful renewal of such calamities. . Torrents have proved destructive on the continent of Europe by washing away ‘fertile soil, by undermining houses and fields, and whole villages and towns, and causing their fall, by burying fields and vineyards and towns in the debris thus produces, and swept away, and by producing extensive inundations of lower lying evel lands, drowning man and beast, and burying, washing away, or otherwise destroying the labour of years. Your readers will know to what extent the parallel holds, and to what extent it fails, in the destructive effects of torrents at the Cape, or in the districts in which they reside. Having thus indicated the evil, I would briefly advert to thé remedial measures which have been adopted. One of the means employed to avert destruction when it was threatened, was the erection on the river-bed of protecting walls, and’of advanced structures, to ‘determine ‘the current, and of continuous slopes to regulate its rapidity and force, and of combined and modified forms of all of these appliances, which manifested great art and skill, ingenuity, and power. It would be exaggeration to say they proved in every case an utter failure, but this would only be an exaggeration of what was the fact, which was, that in very many cases they failed to avert the evil, and in not a few.cases they were carried away before the torrent like chaff before the wind, while the torrent seemed to laugh a loud and hollow laugh at the silliness of man’s device. To prevent the destruction of land by inundations, the more promising measure of raising embanknients based or founded on the dry land was adopted, and the river was thus chained within its bed, with only liberty of action within a limited space beyond. But what did the river do? It silted up its bed, and thus raised itself, and attempted to overflow the embankment. ‘The danger was perceived in time, and the embankments were raised to a higher elevation. The river quietly repeated the silting up of its bed, which was met by a repeated addition to the embankment. This was done again and again. It was a continuous struggle between dead matter and living mind, carried on for years—for genera- tions,—buth refusing to give in. Meanwhile, as in the case of the River Po, not only the embankments, but the silted-up bed of the river was elevated consider- ably above the level of the country lying on one side and on the other, an aqueduct of earth overtopping and threatening with destruction houses and trees and man and beast alike, Then it was a desperate and a deadly struggle, which many saw it would have been well it had never been entered on, while others looked on and said, It is evident that that is not the way in which the evil is to be averted. Meanwhile the struggle was continued, until a breach was at length effected in the embankment, and the river poured forth its torrent, inundating the country far and wide. While this contest was going on, the study of torrents in the Alps revealed th form of the bed of these to be a large somewhat semi-circular Uiauel sta pad basin, from the rainfall in which the waters were collected,—a channel more or PROPACE, iii less elongated, along which the waters flowed,—and a fan-shaped bed of deposit corresponding to the delta of a river, the whole being like to a river-bed redueed or contracted in length; it showed, further, that these torrents were to be met with in all stages of progress, from incipient formation, throughout various stages of activity, to final extinction ; it showed that in forest-covered mountain regions there were none; that in denuded mountain ranges they were numerous, and sometimes very destructive; that, where they were extinct, the forest: had extended itself till it covered the basin and lined the banks of the channel ; that, where they were in a state of progressive extinction, the forests were progressively extending themselves ; and that this extension of the forest was apparently the cause or occasion of the extinction of the torrent. From what had thus been observed the inference was drawn that by artificial plantation the gradual extinction or the subjection of the torrent to control might be effected;—and numerous facts which had been long known were recalled to give their testimony in confirmation of the correctness of the inference drawn. Rain falling on a metallic roof rushes off, while the same rain falling on a thatched roof trickles down in drops; from the bared ground the rain runs off in streamlets long before it runs off in a similar way from the grass-fiéld or the thicket ; and the more the phenomena of percolation and drainage was studied, the more manifest did it become that vegetation retarded the flow and prevented. the rush of water, retained it to moisten the soil, and extinguished the torrent, requiring the river to take days and weeks to carry away what the torrent carried away in hours, and thus securing something like a permanent flow in what had become a dry channel, filled occasionally from baak to bank with a destructive torrent, converting the lion into a lamb. And now millions of franes are being spent on the work of planting trees, and herbage, and bush, with a view to preventing torrents and inundations destroying the land. It does not comport with my purpose to discuss details. I wish simply to open up the previous question, —Is it expedient to give consideration to this? It may be objected,—It would be a gigantic work by which anything could be done. to bridle the torrents of the Cape! It would; uo one knows that‘bettér'than I do and I think it probable that no one has any such conception of the magnitude. of the enterprize as [ have ; but it is by gigantic struggles that the capabilities of ,a people are developed. It may be objected,—It would require a gigantic expendi- ture! It would; but what is the cost of the destruction of property, to say nothing of the destruction of life, which these torrents at present occasion ? i have before me details of destructive effects of torrents which have occurred singe I left the Colony in the beginning of 1867. ‘Lowards the close of that year there occurred one, the damage occasiuned by which to roads and to house property at Port: Elizabeth alone wus-estimated: at from £25;000 to £30,000. Within a year thereafter a similar destructive torrent occurred at Natal, in regard to which it was stated that the damage done to public works alone was estimated at £50,000, while the loss to private persons was estimated variously from £50,000 to £100,000. In the following year, 1869, a torrent in the Western Province occasioned the fall of a railway bridge, which issued in logs of. life and loss of property, and personal injuries, for one case alone of which the railway pro- _prietors were prosecuted for damages amounting to £5000. In Beaufort, West:a deluge of rain washed down the dam, and the next year the town was flooded by. the waters of the Gamka; and the next year, 1871, Victoria West was visited with a similar disaster. Such are the sums and the damages with which we ‘have to deal in connection with this question, as it affects the case ; and these are only the most remarkable torrents of the several years referred to. I have spoken of millions of francs being spent on FReboisement in France; and. some may'be ready to cry out, “ Nothing like such an expenditure can be undertaken at the Cape!” Perhaps not ; but the losses occasioned by the torrents seem to amount at present to about a million of francs in the year. This falls in a great measure on individuals, that would fall on the community ; and the community in return would benefit by water retained to fertilize the earth, instead of being lost in the. sea,.and by firewood and timber ‘being grown-where now.there:is none. ‘These iv PREFACE. are facta well-deserving of consideration in the discussion of the expediency of planting Crown lands with trees, Towards the close of last year, 1874, still more disastrous effects were produced by torrential floods. According to the report given by one of the Colonial newspapers, the damages done could not be estimated at much less than £300,000. According to the report given by another, the damage done to public works alone was esti- mated at £350,000,—eight millions, seven hundred and fifty thousand francs. And my attention was called anew to the subject. On addressing myself to M. Faré, Director General of the Admini- stration of Forests in France, there was afforded to me every facility I could desire for extending and verifying the information I had previously collected in regard to the works of reboisement to which I have referred. Copies of additional documents were supplied to me, with copies of works sanctioned by the Administration, and arrange- ments were made for my visiting and inspecting, with every assistance required, the works begun and the works completed ; and thus I have been enabled to submit a much more complete report than it would otherwise have been in my power to produce. While the compilation I have prepared owes its publication at this time to the occurrence of the inundations of last year at the Cape of Good Hope, the publication has been undertaken in the hope that in other countries beside South Africa the information may be turned to practical account. It may prevent misapprehension if I state that I do not for a moment suppose that the measures adopted to control Alpine torrents are measures to be adopted in their entirety, and without modification, to control all torrential floods. I profess only to supply information in regard to what has been done in certain definite circumstances; and thus to place the practical hydraulic engineer, who may have to prescribe for special cases which may be somewhat analogous, in possession of the information I happen to have collected in regard to what has been done in France, leaving him to turn this to practical account as he may. I may add, it was not until twenty years after the publication of the work by M. Surell, which is considered to be the work which gave rise to the operations now being carried on in France, that these operations were commenced ; and this was upwards of sixty years after similar views had been published by Fabre. And in view of this fact, I shall not be surprised, nor shall I be discouraged PREFACE. v in endeavouring to develope the resources and agricultural capabilities of Southern Africa, though nothing should be done in my life-time towards carrying out my suggestions in regard to the application of remedial measures to prevent the occurrence of devastating torrential floods. I am quite aware that time is required for information to permeate any community, and that this is more especially the case where the population is sparse and pre-occupied with pastoral and agricultural operations. To meet this disadvantage as far as I can, I have made arrange- ments similar to those made in regard to the treatise on the Hydrology of South Africa, for copies being transmitted to any Post Office in the world accessible by the Book Post from Britain, And in anticipation of what may be done at some future time to employ plantations of trees as a means of preventing the occurrence and the destructive effects of torrential floods at the Cape of Good Hope, I may here put on record that appended to Report of Colonial Botanist for 1868 are—(1) A memoir on the Conservation and Extension of Forests as a means of counteracting disastrous consequences following the destruction of Bush and Herbage by fire; (2) A Letter to Rev. W. Stegman, Adelaide, on the spread of the Rhinoster Bush; (3) A letter to Mr Hayward, Swellendam, on the planting of trees by water- courses. Appended to Report of Colonial Botanist for 1865 are— (1) A letter to J. F. J. Wrensch, Esq., Secretary to Divisional Council of district of Albert, on trees deemed suitable for culture in that and similar districts; (2) A letter to J. H. L. Schumann, Esq., Aberdeen, South Africa, on trees deemed suitable for culture in the Karroo and Sweet veldt; (3) A letter to E. L. Layard, Esq., on trees suitable for culture at Cape l’Agulhas and other districts exposed to a strong sea breeze ; (4) A letter to Dr Mueller (Baron von Mueller) Government Botanist and Director of Melbourne Botanic Garden, relative to shrubs and trees used at the Cape for fences, avenues, and burying- grounds; (5) A letter to Walter G. Fry, Esq., Victoria Tannery, Bristol, relative to Tannin-yielding plants growing in the Colony. And appended to Report of Colonial Botanist for 1866 is—(1) A list of South African trees, shrubs, and arborescent shrubs, upon the natural history, or botanic character, or economic uses of which a report had been prepared ; (2) An abstract of memoir on the forests and forest lands of Southern Africa, with details of the extent and contents of the different forests of the Colony of the Cape, of Kaffir-land, of Natal, and of the regions beyond to the mouth of the Zambesi, and vi PREFACE, to a corresponding latitude on the West Coast, with the intermediate districts ; (8) An abstract of memoir on the Forest Economy of the Colony of the Cape of Good Hope: (4) An abstract of memoir on Arboriculture in South Africa, with details of what has teen done and of what might be done, in planting trees in the Cape Colony with notice of the Natural History of Australian and European trees which have been recommended by arboriculturists for plantation there. JOHN CROUMBIE BROWN. Happinaton, CONTENTS AND ARGUMENT, PAGE. PREFACE, . e r ‘ a | In this is stated the exigence existing in the Cape of Good Hope, and by inference existing elsewhere, for the adoption of measures similar to what have been oo in France to avert the destructive effects of floods and inundations p. 1). IyTRoDUCTION, ; i : : 7 The application of the terms reboz: tand g ¢ is stated ; illustrations of the evils which the operations so designated have been employed to remedy are given in citations descriptive of Devoluy and other places in the High Alps (p. 7); and in further illustration of the same there are cited cor- responding cases from Abyssinia, India, Switzerland, and Italy (p. 11); an ae is given of the fwhn, the wind occasioning the torrents of the Alps p. 13). ; PART I.—Resumé or Surety’s Srupy or ALPINE TORRENTS, . 15 States the position assigned to Surell’s work (p, 15). Section I.—The Phenomena of Alpine Torrents, . : . 15 Gives the distinguishing characteristics of rivers, of torrential rivers, of torrents, and of mountain streams; of different classes of torrents, of glacier torrents, and of torrents blane (p. 15) ; detailed information is given in regard to the beds of torrents, and the continuation of these in the ravines of the mountains, and in regard to the thalweg or inclination of the valleys, and to the operation of flowing water in the formation of these (p. 17); in regard to Bassing de re- ception, or basins drained by torrents (p, 21); to Canauax d'ecoulement, or water- courses; to Lits de dejection, or beds of deposit (p. 23); and in regard to torrential fleods of water ; to the occasion of these, and to the avalanche-like effects produced by them (p. 25). Section I].—Watural History of Alpine Torrents, . , It is stated that there may be seen in the Alps old beds of torrential deposit covered with vegetation of many years growth, which proves that the torrents forming them have long ceased to flow; and that such may be seen in various stages of advancement, indicating different periods of extinction of torrents of a former day (p. 30); that in view of these and other facts observed, the his- tory of a torrent may be considered as marked by three periods—that of the creation of the curve of the bed, that of the deepening and enlarging of this, but with the course inconstant, and that with this stable and fixed,— followed in the cases referred to by the extinction of the torrent (p. 33); that many torrents have originated from mountains, or mountain sides, having ben denuded by the clearing away of forests; and that they have owed their development to the combined operation of deluges of rain (p, 34), the nature of the soil, and the consequent contour of the country(p. 36)—the latter an effect as really as a cause of the flood (p. 38). 30 Section III.—Remedial Appliances to prevent the destructive conse- quences of Torrents, . : . : . . Al What were sought to be prevented were inundations, the washing away of lands, and the ruin of fertile fields by the deposit on them of the detritus washed away (p. 41). Embankments were employed to prevent inundations, but without success (p. 44.) The other evils were not less serious, of which illus- Vv CONTENTS. : Ae aus te trations are given, and the remedies at first employed were retaining Wa')s, palisades, nears of varied structure, and coffers, but the evils still ee (p. 45). It having been observed by M. Surell that the origin of | rene torrents might be traced to the destruction of forests, and that the extine of torrents was attributable to the extension of forests (p. 46), he laid ag as established facts—(1), that the existence of a forest on a soil prevents M f na ; mation of a torrent there, and (2), that the destruction of forests leaves ar subject to become the prey of a torrent;‘and he recommended Do appropriate remedies for the evils experienced, extensive properly ee plantation of trees, the exclusion of cattle from properly selected spots to a A of the growth on these of herbage and bush, and in subordination to the ae ing out of these measures such artificial structures of defence as mig) called for,—which measures are detailed. PART I.—Lirsrarvre ReLative to Anpine TorRENTS, AND RE- MEDIAL MEASURES PROPOSED FOR ADOPTION TO PREVENT 6 THE DISASTROUS CONSEQUENCES FOLLOWING FROM THEM, : Contains notices of treatises and proposals by Fabre, 1759 (p. 55); Lecreulx, 1804 (p. 59); Hericart de Thury, 1806 (p. 59); Ladoucette, 1834 (p. oe Dugied (p, 60), SURELL (p. 65), Delafont (p. 66), Jousse de Fontaniere (p. 6 . Labecke (p. 67), Chevalier (p. 69), Blanqui (p. 70), Bonville (p. 72), Belgran (p. 73), Valles (p. 74), Delbergue-Cormont (p, 75), Rozet (p. 78), Scipion Gras (p. 79), Breton (p. 82), Culmann (p, 84), Revue des Deux Mondes (p. 91), Mar- schand, who treats of the hydroscopicity, capillarity, permeability, and im- permeability of soil (p. 94), Cézanne, in a supplement to Htude des Torrents by Surell, with notices of phenomena referred by him to what he calls a torrential era following the glacial period in pre-Adamite times (p. 101) ; Costa de Bastelica, who treats of what he designates Torrentiality, or torrential phe- nomena, in contradistinction to the flow of limpid water, and alleges that by this may phenomena referred by Cézanne to glacial action be accounted for (p. 111) ; explains the phenomena of stones bounding in advance of a torrent wave (p. 117); discusses the extinction of torrents by botsement (p. 118) ; by gazonnement (p. 121) ; and by barrages (p, 123) ; treats of Colmatage or warp- age in connection with these, and applies his views of torrentiality to ac- count for geological phenomena (p, 127). And thera is given a list of other works on the subject in French (p 129), in German (p. 132), and in Italian (p. 133), and quotations from works in English by Marsh (p. 134), Arthur Young (p, 136), and Duile (136). PART II].—Lecisuative anD Executive MmASURES TAKEN BY THE GOVERNMENT OF FRANCE, IN CONNECTION WITH REBOISEMENT AS A REMEDIAL APPLICATION AGAINST DESTRUCTIVE TORRENTS,. 137 In the 14th century edicts were issued and other means were employed to arrest the destruction of forests, as a means of arresting the destruction which was being wrought by torrents. These are referred to, and there are given translations of the text, and of copious extracts from the Act-Decree of the 4th Thermidor an XIII. relative to the torrents of the department of the High Alps (p. 188); Act of 16th September, 1806, and law of 16th September, 1807, relative to the execution of works required to prevent destructive effects of such torrents (p 140). The state of matters about the time of the publication of Mr Surell’s work, and for some years thereafter, till the destructive inundations in 1856 led to the issue ofa letter from the late Emperor Napoleon, desiring attention to be given to the cause or occasion of such inundations, with a view to the employment of appropriate remedies (p. 147) ; and there are yiven translations in whole of (1) the Report given in reply to the Emperor by the Minister of Finance, pub- lished 3rd February 1860 (p. 147); (2) Law founded thereon, promulgated on 28th July 1860 (p. 12); (3) Cireular in relation thereto, addressed to Con- servators of forests by the Director General of the Forest Administration on 17th August 1860 (p. 154); (4) Decree embodying the Statute of the Public Administration for the enforcement of the said Jaws issued 27th April 1861; (5) Cireular addressed to Conservators of forest by the Director General of the Forest Admin‘stration communicating explanations of said decree, issued 1st June 1861 (p. 163), Translations in whole or in part are given of (1) Resu né of First Annual Conference of Agents employed, instituted by Ministerial decision of 21st November 1861, and held on the 9th, 10th, and 11th December, at Valance for the region of the Alps, at Aurillac for the region of mountains in central France, and at Tarbes for the region of the Pyrenees (p, 171); (2) Report for 1861 CONTENTS. (p. 180); (3) Résumé of the Second of the Annual Conferences of forest agents specially charged with the replanting of mountains with woods in the different districts of France, instituted by Ministerial decision of 21st Nov. 1861. held on 8th September 1862, and days following, at Clermont Fer- rand for the region of the mountains of central France; at the same date, at Carpentras for the region of the Alps; and on 15th Sep, and days following, at Foix for the region of the Pyrenees (p. 181) ; (4) Report for 1862 (p. 200) ; (5) Report for 1863 (p. 293) ; (6) Report for 1864 (p, 206) ; (7) Report for 1865-66 ; (8) Report for 1867-68. To meet difficulties arising out of popular opposition to the operations, a mixed com- mission was appointed to carry out in combination this law and a land-improve- ment act which had been passed at the same time, uhder the title Lot du 28 juillet 1860, relative & la mise en valeur des Marais et des Terres incultes appar- tenant aux Communes ; but this measure having failed to meet the case (p. 208), additional legislation was required; and there are given translations of (1) Exposé des Motifs, or reasons assigned for the legislation (p, 209); (2) The Supple- mentary Law of 8th June 1864, completing in regard to gazonnement the law of 28th July, in regard to the reboisement of the mountains (p.215); and (3) The Decree embodying the regulations of the Public Administration of the two laws of the 28th July 1860 and the 8th June 1861, in regard to the rebor: éand g ment of the mountains (p, 2!6). In 1865 this Jaw came into operation, and there is reported what was done in the years 1865 and 1866 (p. 223), Some delay had occurred in the opening of this report, and the Administration was enabled to embody in this a report of the success of the operation, as tested by extensive inundations which occurred in the autumn of 1866 (p, 224); and a report on the difference between the expense of the works of rebodsement and works of gazonnement, and the cause or occasion of this difference (p. 239), In August 1866 there was issued by the Director-General of the Adminis- tration of Forests a circular containing instructions and directions in regard to all matters pertaining to the work (p, 231), Aud with the report of operations in the years 1867 and 1868 was given a tabulated statement of the areas upon whic’ operations had been carried out in the several years which had elapsed from the publication of the law of 28th July 1860, with a statement of the expenditure involved (p. 231) PART IV.—Past, PRESENT, AND Prospective ASPECTS OF THE Work, ‘ ‘ Cuar. I.—Past History of Alpine Torrents, P ; ; Information supplementary to what had been given in connection with the con- sideration of the literature of this subject is supplied in regard to the views of Marsh (p. 235), of Marschand (p. 236), and Gras (p. 237) in regard to the past history of torrents in France. Cuap. I]. —L£xisting Forests, : : . ; ‘ There is cited the testimony of Becquerel in regard to the extent of existing forests in France, and of Marschand in regard to the position of forests in the mountain ranges (p. 238). Cuap. II].—Laws Regulating the Reboisement Hffected and Measures Adopted, : : There is cited an abortive law submitted to the Chamber of Deputies in the Session of 1847, and in connection with a reference to the cause of its failure to effect anything is stated wherein the law of 1860 differed from it (p. 240); and there are enumerated and described the kinds of works by which the object of this law had been accomplished during the first decade of the operations carried on (p, 241), Cuap. IV.—Devastations occasioned by Torrents which it was sought to Arrest and Prevent, and Measures employed, . , j Details are given to show, as was subsequently seen by the population of the moun- taius, that in the operations carried on they had a beneficiary interest as real as that of inhabitants of the valleys and of the plains, for which they considered that their interests were being eacrificed (p. 242); a brief but detailed descrip- tion of the measures employed is given (p. 249); and of the kinds of trees and bushes made use of in different situations (p. 254), and different localities (p. 256). Cuap. V.—Devastations and Restorations, . ‘ ‘ z In this chapter are given detailed information in regard to the work being carried on in different localities within the first decade, showing what was undertaken and what had been effected in different departments of France, embracing the following :— 234 234 238 239 242 257 vi CONTENTS. Szor. L.—The High Alps, . e i ‘ ‘ . There is given the description of the state of devastation which moved Surell to act (p. 258), cited by the Director-General of the Forest Administration, with details of what had been effected in remedying the evil, given by M. Gentil in a report to Conseil General des Hautes Alpes in 1869 (p. 259), and a corres- ponding report given in 1868 by a commission appointed by that body (p. 260); and this is followed by details of what had been the state of the valley of the Durance (p, 261), and of what had been done (p, 264), and with what results (p, 265). Szot. II.—Department of the Isére, ‘ ; ; : There is given an account of Dauphiny and Provence by Marsh, based on a work by Charles de Ribbe (p. 267), and detailed information of what had been done in the périmétre of the Bourg-d'Oisans (p. 268). Szor. III].—Department of the Dréme, ; ; : : This department was formerly included in the Independent State of Dauphiny. There is detailed what had been done in the périmétre of Luc in the arrondisse- ment of Die (p 271). Szot, IV.—The Lower Alps, F : : . ; Details are given of what had been done in the périmétre of Labouret in the arrondissement of Digne (p. 272), and notices of what had been effected by Jourdan, a simple forest warder (p. 274). Szor. V.—Department of the Ardéche in Central France, . ; Information in regard to this district is supplied in the words of M. Marsh, founded on statements by M. Mardigny (p. 275), and corresponding information supplied by M. Cézanne (p. 278). Szor. VI.—Department of the Gard, : ‘ 5 : mass are given of works undertaken and executed in the périmétre of Ponteils p. 279). Szor. VII.—Department of Lozére, . : ‘ : i The sad condition of the district, and the benefits of boisement are described as de- scribed by the prefect of Lozére (p. 280). Szor. VIII.—Department of the Loire and of Haute Loire, ‘ The practicability of improving the basin of the Loire by boisement, as described by M. Cézanne (p. 283). Szor. IX.—Department of Herault, : : : Details are given of works executed in the périmetre of Riols (p. 284). Szor. X.—TZhe Pyrenees, . ; The French Pyrenees are deseribed by Weld (p. 285-291), and there is reported tha reboisement in périmetre of Bareges (p. 297). Szot. XI.—Department of Aude, . ‘ : : Details are given of operations in the périmbtre of l'Argente-Double (p. 307), Cuap. VI.—Local Feeling and Public Opinion in regard to Reboise- ment, : 7 . : . 2 : There is given information in regard to proceedings in different sessions of the Conseil Général of the High Alps (p, 312), to change of tone after 1865 (p. 313) to testimony of M. Sequinard, Conservator of Forests in the district (p. 314), to testimony of commissioners appointed by the Conseil Général (p. 316) to proceedings in the Conseil Généraux of other departments (p. 317), to testimony of M. Faré, Director General of the Administration of Forests (p. 318), aud of the National Assembly (p. 319). , Cuap. VII.—Present Position and Prospects of the Enterprise, , There are cited anticipations by M. Surell (p. 321), description of the present by M. Cezanne (p. 323), and details by M. Gentil of what has been effected (p. 324). ConcLusion, . There is given an account of the inundation of Toulouse '329 and of Hi : (p. 337), and Port Elizabeth in South Africa, as diosa B a phase persed fons commen oe eae Fie lola reboisement may meet, and the first men- joned, the inundation of Toulouse, is studied in the ligh steered Ge aa3) A @ light of what has been 257 267 271 272 275 279 307 311 320 328 INDEX OF AUTHORITIES CITED IN ADDITION TO OFFICIAL DOCUMENTS EMBODIED IN THE OOMPILATION. Antoine d'Abadie, page 11, Battivilla, 133. Becquerel, 238, Belancier, 129. Belgrand, 78, 129, 181. Berlepsch, 183, Blanqui, 70, Bonville, 72. Breton, 82,103. Broignard, 74. Caimi, 133. Castellani, 1383. Cereni, 183. Cézanne, 79, 81, 82, 84, 85, 86, 90, 101, 181, 146, 208, 234, 236, 240, 243, 244, 249, 257, 261, 263, 274, 283, 312, 314, 323, 327. Champien, 74. Chevalier, 61. Chevandier de Veldrom, 209. Colegnon, 129. Colomb, 108. Cérnoy, 127. Costa de Bastelica, 111, 235, 266. Culmann, 81, 84, 89, 115. Daily News, 331. Darcy et Bazin, 129. Delafont, 66. Belbergue-Cormant, 75, Dugied, 35, 60. Duile, 132, 136. Dumont, 129,145. Dupuit, 130. Eastern Province Herald, 339. Escher, 89. Fabre, 55. Fairbairn, 336. Faré, 231,318. Fargue, 130. Fossombroni, 133. Foutnie, 180. Frank Hausen, 251. Gentil, 324. Gauloes, 332. Graeff, 130. Gras, 79, 237, 243. Guide Joanne, 87. Hagen, 131. Hall, 334. Hericart de Thury, 59, 97. Heyer, 132. Jamieson, 106. Journal des Debats, 333, 346, 348, Jousse de Fontaniere, 10, 66 Kloden, 1382. Krantz, 180. Labecke, 67, Labuissiere, 91, 274. Ladoucette, 60, 67, 75, 77, 242. Lamairesse, 180. lLavignot, 74, Laydeker, 224, 229, Lecreulx, 59. L’Moine, 131. Léonce de Lavergne, 262. Lombardini, 79. Lorentz, 256. Lorgna, 133. Magne, 74, 147, 289. Malézieux, 130, Mangon, 130, Marschand, 13, 94, 132, 286, 238, 248, 251. Mardigny, 74, 257. Marsh, 8, 11, 29, 70, 72, 73, 74, 78, 114, 134, 187, 146, 235, 245, 267,275. Martins, 106, 108, Monestier- Savigonot, 130. Montleussant, 60, 266. Morell, 11. Morgue, 10. Muller, 183. Nadault de Buffon, 130. Nanquette, 256. Palissy, 78. Paoli, 183, Parade, 256. Partiot, 180, De Paasy, 130. Picol, 130. Philips, 338. Plocq, 130. Poirée, 130. Rapport au Conseil Provincial de Luxemburg, 180. Rappen, 183. Reclus, 248. Ribbe, 74, 266. Rosa, 133. Rozet, 74, 78. Sache, 95. Schlangenweit, 11. Scipion Gras, 79, 237, 243. Sequinard, 314, Spectator, 349, Standard, 331. Streffleur, 131. Surell, 7, 15, 54, 58, 59, 63, 65, 77, 114, 141, 257, 263, 821. Tallon, 319. Tartini, 133. Thurmann, 96. Times, 330, Tray, 75. Valles, 74. Van den Brinken, 133. Venez, 87. Vigan,130. Vicaire, 154, 163, 171, 180, Von Arrentin, 131. Von Berg, 132. Von Zaltinger, 131, Weld, 285, 296. Wessely, 133. Young, 72, 136. Zanotti, 138, REBOISEMENT IN FRANCE, INTRODUCTION. One of the striking features of the scenery of. extensive districts in the High Alps is that presented by numerous ravines, of greater or less depth and extent, furrowing the mountains, created by mountain floods, These are the Torrents of the High Alps. In the creation of these much valuable lad, and in some cases houses and fields, have been undermined, precipi- tated into the water-course, and washed away; and land not less valuable hps been devastated by being covered with the detritus. The most efficacious means of preventing the formation of torrential floods have been found to be what are designated reboisement and gazonnement,—the former being the replanting with woods lands in the districts formerly covered with forests which have been denuded of these, the latter the creating of a dense turf of herbage and bush upon adjacent ground. Evils similar in kind but differing in degree are not unknown in several newly-settled lands. The success with which these remedial operations have been carried out in France may commend them as appropriate appliances to remedy these evils; and the magnitude of the evil which is being combated and remedied in France may be considered as calculated to ’ speak encouragement to those who are called to meet only lesser forms of the evil. Under this impression I would here cite details which have been given of the form and magnitude which the evil had assumed, and in which it has been attacked with success. The first I shall cite relates to the Dévoluy. Of this valley Surell writes,—‘ The Dévoluy forms to the west of the department of the High Alps an elongated valley, divided into two parts by a little col and circum- scribed by elevated mountain chains. It is entered by five passages, which are gorges or cols which the horrors of the locality make impracticable for passage during a part of the winter. The mountains are bare,—eaten up by the flocks and by the sun ; they are without shade and without verdure. The bases of the mountains are almost deserts, having been ruined by the Ceposit of material dejected from ravines, The aspect of this miserable country is oppressive to the soul: one would say of it, It is smitten with death. The pale and uniform colour of the soil, the silence which weighs on the fields, the hideous spectacle of these mountains flayed by the waters 8 INTRODUCTION, and falling into disintegration, and everything about them, announces miserably ruined, decrepitated land, which does not appear even to struggle against, or resist, or resent its destruction. The unchanging serenity of the sky, which anywhere else would be a trait of beauty, adds here to the melancholy sadness of the country. I shall go over step by step the errors of man which have brought about this state of things. “Everything concurs to show that in ancient times this country was wooded. There are dug up from its peat bogs buried trunks of trees— monuments of ancient vegetation. In the frame-work of old houses are seen pieces of enormous timber such as is not now to be found in the district. Many localites completely bare still bear, even to-day, the name of wood. One of these valleys (that of Agnéres) is called, in old deeds, Comba-nigra, on account of its thick forests. By these evidences, and many others, are confirmed the traditions of the district, which are, on this point, unanimous. “There, as in all the High Alps, the destruction of the forests began on the flanks of the mountains, and thence descended little by little towards the depths of the valleys, and ascended to the highest accessible peaks. Then came the late Revolution which caused to fall the remainder of the woods which had escaped the first devastation. This last destruction was accomplished under the eyes of some of the present population, and all the old men remember what the forest was in a former day.” He adds in a note :—“ And many have told me that they have lost flocks of sheep straying in the forests of Mount Auroux, which covered the flanks of the mountain from La Cluse to Agnéres. These flanks are to-day as bare as my hand.” 1 “ And,” he resumes, “ there, after the destruction of the forests, have come also the grubbing up of roots and the pasturing of flocks. They grubbed up the grounds nearest to the dwelling-places. Theylet the flocks go freely every- where, wherever it was inconvenient or impossible to transport the ploughs. This proceeding, begun centuries ago, accelerated by the Revolution, has produced its inevitable fruits, and the inhabitants suffer sorely to-day from the improvidence of their fathers. “The first evil to be noticed is the extreme rarity of woods. The communes are burdened with the purchase, at great expense, of the possession of distant forests. It requires in certain localities, as for instance at Saint Etienne, thirteen hours of fatiguing work to convey, on the back of a mule, a load of wood across the fearful precipices, and this without reckoning the time occupied in felling and cutting. Other communes, for example La Cluse and Saint Disdier, have preserved woods which, with the greatest economy, might suffice to meet their wants, but they are not more happy ; and this fact makes it apparent that the forests have a function to fulfil here other than simply that of satisfying the daily wants of the inhabitants. For, first the clearances, then the plough and the flocks, have so dissipated the vegetable soil that there now remains no more of it than a thin bed formed by the disintegration of the rock which underlies it, and which now protrudes through it on all hands. Such is the mobility of this ground that it is washed away by the slightest showers and leaves an arid bottom in the place of cultivated fields, Every storm gives rise to a new torrent.” In confirmation of this it is stated by Marsh in his treatise on The Eart as Modified by Human Action,—“No attentive observer can frequent es INTRODUCTION, 9 southern flank of the Piedmontese Alps or the French province of Dauphiny for half-a-dozen of years without witnessing with his own eyes the forma- tion and increase of torrents. I can bear personal testimony to the conver- sion of more than one grassy slope into the bed of a furious torrent by the baring of the hills above of their woods.” And Surell goes on to say,— There can be shown here torrents, which have not been in existence for three years, which have destroyed the finest parts of the valleys. Whole villages have been almost carried away by ravines formed in a few hours; and the greater part of the torrents have not as yet received a name. Often the wild waters, flowing in broad sheets over the surface of the ground, without bed, without ravine, without torrent, have sufficed to soak and ruin whole districts which have been abandoned for ever. “One may see also dispersed here and there on the brows of many hills (revers), traces of old fields and of old estates, the bounds of which are still marked out by thick dry stone-walls, but which no man has been near for along time. Such are to be seen on the rising grounds of Agnéres, and on the col of the Noyer. One can with difficulty imagine anything more dis- tressing and more significant than the sight of these ruins; they have written on the brows of hills (revers) of the Dévoluy the future destiny of all the French Alps. And here again come into view proofs which do not admit of any doubt in regard to the destructive influence of flocks. Some communes, dreading the future, have enclosed some quarters, as the mountain of Chaumette, quartier de Maniboux, quartier de Lierravesse, quartier de Auroux, near Saint Etienne. Immediately vegetation had again gained possession of the soil, the herbage, bushes, and shrubs have spread with wonderful rapidity, and formed what are called dlanches in the country. Whole forests have sprung up on the soil of the forests which were destroyed at the Revolution, but which the inhabitants, now inspired with a better feeling, have subjected to a regular course of forest management. Finally, on the same mountain brows (revers ) enclosed portions assume, by the end of two years, appearances different from that of those given up to the sheep. The latter are bare and cut into ravines ; the former are covered with vege- tation, the soil is consolidated, and the ravines, carpeted with tufted plants, look like cicatrices occasioned by wounds, which are under the benignant influence of a topical application. In the two quarters—the exposure, the slopes, the soil are the same ; the mere fact of putting them en reserve has determined the difference. What can be objected to such facts? Are they not conclusive? Do they not give the clue to the system to be followed to put at last a stop to these calamities always increasing ? “To resume, we see here always the same effects resulting from the same causes. Let us follow them a little further and we find them become still more saddening. “The country is being depopulated day by day. Ruined in their cultiva- tion of the ground the inhabitants emigrate to a great distance from this desolated land, and, contrary to the general custom of mountaineers, many never return. There may be seen on all hands cabins deserted or in ruins, and already in some localities there are more fields than labourers. “The precarious state of these fields discourages the population. They abandon the plough and invest all their resources in flocks. But these flocks expedite the ruin of the country, which would be destroyed by them alone. Every year their number diminishes in consequence of want of 10 INTRODUCTION. pasture-grounds. The number of sheep which was 53,000 twenty years ago are now only 36,000. One commune, Saint Etienne, which supported 25,000 sheep fifteen years ago, supports no more than 11,000 now. Thus the inhabitants, who sacrifice all their soil for the flocks, will not even leave this last inheritance to their descendants. “Thus may one see clearly whither tends this fatal chain of causes and effects, which commences with the destruction of the forests and ends in suffering and misery for the population, condemning man also to share the ruin of the soil which he devastated. “ All these facts have been lately recounted by M. Morgue, the present Prefect of the High Alps, in a memoir which treats specially of this unhappy valley. ‘The history of Dévoluy,’ says he, in closing his memoir, ‘will be that of the High Alps before five centuries have passed if the indifference of the Legislature go on, if the recklessness of the Administration continue, and if nothing occur to arrest the cupidity of the communes.’ We may place side by side with these words those of a former Prefect of the Low Alps, M. Dugied, in a memoir on the subject. ‘Such,’ says he, ‘are the causes of the sad condition of the department. One may affirm with certainty that, of a remedy be not speedily applied, ere long the population em the upper portion will go on diminishing, and that with a rapidity which can only be accounted for by that which went on before. I do not know if I deceive myself, but I believe it is possible to remedy the evil ; and-I believe, moreover, that it is high time to set about this. Wait a quarter of a century and perhaps it will be too late, because the best grounds which exist on the mountains furrowed by the storms may then have been carried away by the floods.’” In accordance with the forebodings of Surell were the following forebod- ings of M. Jonsse de Fontaniére, Inspector of Forests, embodied in a memoir, Sur la degradation des foréts dans les arrondisements d’ Lmbrun et de Briancon, “From all that has been said the conclusion may be drawn that the department of the High Alps is the one, in all France, in which the cultivators of the land are most menaced in their fortunes, and that they will be compelled, and that sooner than they dream of, to abandon the places which were inhabited by their forefathers; and this solely in con- sequence of the destruction of the soil, which, after having supported so many generations, is giving place, little by little, to sterile rocks. “Tt is the destruction of forests which will be the principal cause of the calamity. The torrents, becoming more and more devastators of the country, in consequence of the destruction of these, will bury under their deposits extensive grounds which will be lost for ever to agriculture. The hills, denuded of their vegetable soils, will no longer admit of the infiltra- tion of water. Then sources of streams and rivulets will be exhausted, and the drought of the summers not being moderated by their irrigation all vegetation will be destroyed. ss , . “The destructive elements thus give birth one to another, and it is only necessary to notice what is going on to-day to foretell what will infallibly come to pass some ages hence—when the forests shall at last have entirely disappeared—fuel and water, the two first necessaries of life, will then fail from these desolated countries. “The cupidity of the inhabitants, and the tenacity with which they hold to old usages, admit of no hope that any moral conviction in regard to their future will so impress them as to lead them to submit willingly to a tem- INTRODUCTION, i porary sacrifice. It is for the Administration, more enlightened than they on the state of things and on the consequences which are coming, to meet the evil by legislation appropriate to the requirements of the country.” Varied is the tone in which like forewarning was given by different fay- seeing men, who gave their attention to the subject, about the time in which these forebodings were published. ; To one unacquainted with the facts of the case such forebodings of evi may appear extravagant. To one knowing something of these facts they appear legitimate and true; and to one who has seen the region in some of ita aspects they seem to be not unreasonable. But the truth is not always truth-like, and to remove any lingering incredulity I may state that the torrents of the High Alps are equalled and even exceeded by torrents seen elsewhere. The traveller, Antoine d’Abadie, who was almost frozen to death in climbing the Wosho,—a mountain of Abyssinia, 5060 métres, upwards of 16,000 feet, above the level of the sea, gives the following picture of what he witnessed :—‘ Sometimes we would be going on in all security under a serene sky, when a native, hearing a strange noise at a distance, which quickly increased, would cry out with all his might, The torrent! and with all haste clamber up upon the nearest height. Thirty seconds would not have elapsed when the bottom of the valley totally disappeared under a sheet of water, which swept away with it trees, blocks of rock, and even wild beasts. These torrents, formed in a moment, exhaust themselves in the course of the same day, and leave no trace of their passage but debris of all sorts and pools of muddy water retained here and there in the clefts and hollows.” M. d’Abadie relates that one day he arrived at a spot just a little too late to see in all its grandeur one of these sudden inundations. He found only a native, looking with a dumfoundered air on the wet ground. “Good morning,” said-the traveller. ‘‘ What has happened to you? Where are our drms? Can aman like you stand there without lance or buckler 2” “Good morning,” answered the African, “and health be yours! The torrent has carried off my lance, my buckler, my camel, and all my possession ; my wife, and my children. Wretched me! Wretched me!” Such are the torrents of Abyssinia. The brothers Schlangenweit, writing of the energy of the torrents of the Himalayas, state it as their belief that they will cut gorges through that lofty chain wide enough to admit the passage of currents of warm wind from the south, and thereby modify the climate of the countries lying to the north of the mountains. Morell, in his Scientific Guide to Switzerland, mentions that about an hour from Thusis, on the Spluegen road, “ opens the awful chasm of the Nolla, which a hundred years ago poured its peaceful waters through smiling meadows protected by the wooded slopes of the mountains. But the woods were cut down, and with them departed the rich pastures—the pride of that, valley—now covered with piles of rock and rubbish swept down from the mountains.” And he goes on to say,—‘‘ The result is the more to be lamented as it was entirely compassed by the improvidence of man in thinning the forest.” Marsh, citing a pamphlet published at Brescia in 1851, entitled Dellu Inandacioni del Mella nella notte del 14 al 15 Agosto 1850, says,—“ The 12 INTRODUCTION. recent changes in the character of the Mella—a river anciently so remark- able for the gentleness of its currents that it was specially noticed by Catullus as flowing molle flumene—deserves more than a passing remark. This river rises in the mountain chain east of Lake Iseo, and traversing the district of Brescia, empties into the Oglio after a course of about seventy miles. The iron-works in the upper valley of the Mella had long created a considerable demand for wood, but their operations were not so extensive as to occasion any very sudden or general destruction of the forests, and the only evil experienced from the clearings was the gradual diminution of the volume of the river. Within the last thirty years the superior qualities of the arms manufactured at Brescia has greatly enlarged the sale of them, and very naturally stimulated the activity of both the forges and of the colliers who supply them, and the hill-sides have been rapidly striped of their timber. Up to 1850 no destructive inundation of the Mella had been recorded. Buildings in great numbers had been erected upon its margin, ' and its valley was conspicuous for its rural beauty and for its fertility. But when the denudation of the mountains had reached a certain point, avenging nature began the work of retribution. In the spring and summer of 1850 several new torrents were suddenly formed in the upper tributary valleys, and on the 14th and 15th of August in that year a fall of rain, not heavier than had been often experienced, produced a flood which not only inundated much ground never before overflowed, but destroyed a great number of bridges, dams, factories, and other valuable structures, and what was a far more serious evil, swept off from the rocks an incredible extent of soil, and converted one of the most beautiful valleys of the Italian Alps into a ravine almost as bare and barren as the savagest gorge of Southern France. The pecuniary damage was estimated at many millions of francs ; and the violence of the catastrophe was deemed so extraordinary, even in a country subject to similar visitations, that the sympathy excited for the sufferers produced in five months voluntary contributions for their relief to the amount of nearly 200,000 dollars, or £40,000.” The rendering of Job xiv. 18-19 in the Vulgate is,— “ Mons cadens definit, et saxum transfertur de loco suo ; lapides excavant aquae et alluvione paullatim terra consumiture.” “ The mountain crumbling down comes to an end; and the rock is removed from its place; the waters undermine the stones ; and by inundation little by little the land is laid waste.” This is accurately descriptive of the action of the torrent, and this the author of the pamphlet has prefixed as a motto to his narrative. By Mr Marsh it is stated,—‘‘ The recent date of the change in the character of the Mella is contested, and it is possible that though the extent of the revolution is not exaggerated, the rapidity with which it has taken place may have been.” From such independent testimony inregard to similar phenomena presenting themselves elsewhere, it may be seen that there is nothing incredible in the published reports of the state to which the High Alps had been brought before the operation of reboisement was commenced with a view to arrest the evil. It is with a view of promoting the adoption of a similar remedy for cor- responding evils manifesting themselves in other lands that this compilation has been made, Anticipating that the aridity and limited average rainfall INTRODUCTION. 13 on some lands, on which the remedy would not be inappropriate, may be considered a satisfactory reason for delay, I may state that I admit without hesitation that to produce such torrential flows as has been seen in the Alps the quantity of rain falling there must be very great; but I must add that the effect of the rainfall on water-courses depends more on its dis- tribution over time and space than on its average annual amount, and that orages, or storms of rain, constitute one of the peculiar meteorological phenomena of the High Alps. M. L. Marchand, Garde General dés Foréts, says on this subject,—“ When the torrential rains of the Alps are made a subject of study it is soon seen that they are all of them occasioned by a particular wind called the fehn. These winds are generally violent, and present almost always the character of orages, or storms of rams ; it follows that great quantities of rain are poured down upon the soil ; and to this may be attributed disasters sometimes coming upon spots which seemed to be placed in the best possible situation and circumstances to bear the most persistent rains. “The fehn is a wind which blows from the south, often with extraordinary force ; it is peculiar to the Alps, and is felt throughout their whole extent. Having climbed over Italy where it is no other than the siroco, the following are its chief characteristics :—It comes from the south, but its direction is modified at every step, either by mountain chains or by valleys. Its origin is still a subject of discussion : according to some it originates in the Sahara, according to others it originates in the Gulf of Mexico. It gives to the sky a strangely-marked, peculiar, heavy, whitish aspect ; and the rain falls on the second or third day following its appearance. “The wind arrives on the Mediterranean coast loaded with vapour ; it there encounters that immense calcareous simi-circular wall of the Maritime Alps, and it scales their higher slopes ; but in consequence of their covering of forests, and the great heat concentrated by them, in doing so it only attains a higher temperature. It is rarely the case that the moisture is condensed or precipitated on these countries which it rapidly traverses ; but it cools by degrees as it mounts the Maritime Alps, and on reaching the upper basin of the Var and its affluents it deposits an enormous quantity of water ; then it continues to advance northwards to French Comté, before reaching which latitude it has lost much of its force. “Tf a glance be cast over a map of the Southern Alps, it may be observed that from Mount Viso there part off great chains running perceptibly from east to west ; the fahn comes by the valleys of the basin of the Var, or of the upper sources of the Durance, it strikes upon the first chain parting from the col of the Pas-de-la-Cavale, or of the Grandes-Communes, taking a deviation to the north of Digne. _It is against this chain that the first great storms of rain dash themselves. The clouds in passing over these mountains seek the cols or lower parts, and they arrive in the valley of the Ubaye by the openings of Grange-Commune, of Enchastrayes, of the Col d’Allos, of the Lawerq, of the Bas, and in fine, by the great passage of the mountains of the Seyne. “The fehn forces a passage for itself into the valley of the Durance ; goes up this throughout its whole length ; it makes its way also by some cols of the chains which separate this valley from that of the Ubaye, and more especially by those which are opposite Embrun. “Tf now the forest chart of the country spoken of and the chart of the john be compared, it will be seen that the mountains of Seyne have been 14 INTRODUCTION. cleared of woods, and that the whole southern upper slope of the valley of the Ubaye is devoid of forests; in a word, that all the parts which bear the direct attacks of the fwhn—those which arrest it—force it to ascend them, and to pour upon them masses of water, are all of them almost entirely cleared of woods. Here we have no longer, as is the case above Menton, a tropical sun to warm the soil; the wind has cooled down as it rose higher from the sea, and is obliged with fatal effect to precipitate in the form of rain the moisture it has borne thither ; and at that place where the forests are an absolute necessity, and where the most considerable quantities of water fall, there it is that they have completely disappeared. “This summary is incomplete, but it may suffice to render intelligible the general course of the orages, or storms of rain in the Alps, and the intensity of these on certain parts, which are generally those at which the fehn is compelled to rise considerably or to change its direction. The celebrated torrent of Riou-Bordoux, near Barcelonette, in face of the opening at Allos, is exactly so situated. The portion of the Alps situated below the department of the Isére almost completely relieves the jwhn of its humidity, and this is the classic region of the orages. “The fehn does not confine itself to the production of torrential rains ; it is not less terrible in its action on the snow, and on the glaciers. As has been stated it blows sluggishly and warm for one, two, or three days before the rain appears ; if at this time the ground be covered with snow this is not slow to melt rapidly, and absorbing a great quantity of water it becomes like -a sponge ; then supervenes the rain which expedites the process and brings on a kind of débdcle, or breaking up, and the water arrives in great quantities in the valleys. If the rain do not supervene the action of the fehn may suffice to cause all the snow to melt and to produce great conse- quent disasters.. Tn 1856 the inundations of the valley of Barcelonette had no other cause of production ; the maximum of the flood was attained under a magnificent sky, and all the water came from the melting of the snow which covered the mountain. In Switzerland the terrible inundations of 1868-had in general a double origin—with warm continuous rains were com- bined the melting of the glaciers, It is always in the spring, or with the first snows of October, that the latter torrents are to be dreaded if the mountains be not covered with glaciers ; where this is the case the danger is constant. “The feehn sometimes produces general rains over the whole of the.country over which it blows, but sometimes only local oruyes, or storms of rain. This can easily be accounted for when it is considered that the contour of the Alps:admits of one current of air passing up a valley to be in its cause and in its effects quite independent of a current passing up a neighbouring valley, though they have had a common origin,—and that a difference inthe cooling of the currents of air may occasion a precipitation of rain in one valley. while the neighbouring valleys, being warmer, are enjoying a cloudless sky.” Thus can the immense quantities of water poured down by these torrents be traced to their source, and thus can the immensity of the quantity of water producing these devastations be accounted for. The inquiry ‘brings into view the fact that it is the temporary deluges of rain, and not the mean average annual rainfall, which occasion the torrential floods of the Alps. And there are countries in which the mean average annual rainfall may be very small, when an orage, equalling or exceeding any in the Alps occutring once in a decade, may prove not less destructive than any torrent in-that’ torrentravaged region. PART L RESUME OF SURELL'S STUDY OF THE TORRENTS OF THE HIGH ALPS. OF numerous treatises on subjects connected with the natural history, and the arrest or control of torrents in France, that by M. Surell appears to have been that which has done most to give the direction to remedial operations which has been pursued thus far with the happiest results. There were writers before him who anticipated him in some of his sugges- tions, and there are writers of the present day who have suggested more advanced operations ; but that the work of Surell to which I have referred had the effect [ have indicated seems to be proclaimed by all. This work, entitled Htude sur les Torrents des Hantes-Alpes, was printed by order of the Minister of Public Works, and published in Paris in 1841. Theauthor-had been engaged in engineering work on the High Alps, and his first intention was to prepare a few notices of matters connected with engineering for insertion in the Annales des Ponts et Chaussées ; but becoming interested in the subject, and being encouraged by the Prefect of the district, he was led to make a study of water-courses and every thing connected with them. In the sequel I adhere not closely the order in which the several subjects noticed are discussed by him ; but to some extent I follow that order, while the division adopted is my own. Section 1.—The Phenomena of Torrents in the High Alps. M. Surell, to give precision to his treatise which relates to torrents alone, classifies the water-courses of the High Alps as—ruisseaux, or mountain streams ; torrents ; rivieres torrentials, or torrential rivers ; and rivers: and states what he reckons the distinguishing characteristics of these. He refers also to glacier streams, and to what are known as torrents blancs, to point out wherein they differ from what are known as torrents. In what are called torrents blancs the agency of water is scarcely perceived ; it is in operation, but it occupies a very subordinate position ; in torrents it is the one commanding power, acting with apparently resistless force. From the glaciers there proceed currents of water, and by them are formed deposits of stones and rubbish, known as moraines, which might be mistaken for beds of deposit formed by torrents ; but these have character- istics all their own by which they may be easily destinguished from those, The rutsseaux, or mountain streams, are formed of a body of water, small in comparison with the torrents of which he treats, and may form cascades but not torrents, though they may become feeders of these. He describes the rivers of the High Alps, of which he enumerates four, as flowing in wide valleys enclosed-by elevated ranges of mountains or of hills, , 16 RESUME OF SURELL'S STUDY OF and as forming larger bodies of water which, when swollen, continue so for a time more or less protracted ; the slope of their fall is constant throughout long stretches, and does not exceed 15 millimeters per metre, or a fall of 15 in a thousand. They are in many places characterised by a water- course in a level bed of very great breadth, a small portion of which only is taken up by such a water-course, and this is liable to be forsaken and left dry, while the waters flow in another channel which they have formed for themselves, to be again changed for another, and that again after a time for another ; by which constant changes there is frequently occasioned a great waste of land, and this, if cultivated, must be cultivated at the risk of the whole being swept away—crop and soil together. Elsewhere he mentions that traces of the former existence of ancient lakes are frequent in these mountains, and that it is the constant rule for a water-course, whatever may be the class to which it belongs, when it enters one of these basins, to change its bed when traversing it ; but while this happens once and again, perchance, with others of the different kinds of Alpine water-courses which he has enumerated, it occurs so constantly as a general feature of all the rivers, repeating itself unceasingly throughout the whole of their course, while in the other forms of water-course its occur- rence is only occasional and as it were accidental, that he considers this one of the permanent and specific characteristics of the rivers. Torrents, on the contrary, is a name given to what may be called a dry water-course, along which a tiny stream may be generally seen to flow, but which from time to time is filled with a rushing, roaring, resistless flood. They generally traverse very short valleys, which cut up the moun- tains into buttress-like projections. Their fall throughout the greater part of their course exceeds six centimétres per métre, and it is never less than two centimétres per métre, or two in the hundred. Changes in the slope of their fall succeed one another very closely ; and there is given as a charac- teristic of them that they constantly, if they have not previously done so to a great extent, undermine the sides of their course at one place, and sweep away the debris and deposit it at another, and subsequently change their course above the place at which the deposit has been made,—giving occasion for the same process being again repeated at some other spot. By the rapid fall, the rapid succession of changes in the degrees of this, and their destructive effects, they are distinguished from rivers, and also ‘fom torrential rivers, in the technical classification of water-courses adopted. Of torrential rivers, rivieres torrentiales, in the High Alps, Surell enumerates five, but he intimates that there are many more. They are affluents to the principal rivers. The valleys in which they flow are less extensive and more compressed, and they cut up the mountain range into spurs and lesser chains. Variations in the slope of their fall succeed each other more closely than do those of the rivers. They do not change their courses as do these, or they do so but little. Their fall is greater, but it does not exceed six centimétres per métre, or six in the hundred. "The have not the characteristics or specific characters assigned to rivers : naithae do they present the characteristics or specific characters assigned ‘to torrents ; they present characteristics of both with characteristics peculiar to them. selves ; and they are classed apart that the field may be clear for the stud of what are known specifically as torrents. a While the distinctions thus drawn between torrents and other water. courses is maintained in the treatise, it is stated that the different fanne TORRENTS OF THE HIGH ALPS, 17 may be considered as passing, by intermediate gradations, into one another, and that the same body of water may in one part of its course appear in one of these forms, and in another part of its course it may appear in another. The torrents thus specified he classifies under three heads, those of each category presenting characteristics by which they may be distinguished from the others. Torrents of the first class take their departure from a col in the mountains and flow through a valley. Those of the second class flow from the mountain-top and follow the line of greatest declivity. Those of the third class take their origin from the flank of the mountain at some distance below the summit. Of these also there are intermediate varieties, and varieties assimilating them to some of the other forms of water-courses. The first class approxi- mate in some of their features to those of torrential rivers ; in the second class all the characteristics of the torrent are prominent, and to this type most of the torrents in the High Alps are conformed ; and the third class often show ravines, with all the secondary characteristics of these. The washing away of earth, and stones, and blocks of rock being one of the constant effects of torrents in the High Alps, and the deposits of the detritus presenting certain constant features whereby they may be distin- guished at a glance, not only from the moraines of a glacier, but from the shot-heap of a land-slip, and from all other earthen mounds whatever, Surell has fixed upon the bed of deposit as the most characteristic indica- tion of the previous action of a torrent, and makes the study of these beds of deposit, or hits de déjection, the point of departure in his study of torrents. ; Of these torrents, he says, in the introduction to his work, “ The depart- ment of the High Alps presents us with water-courses of a singular form. There is given to them in the locality the name of torrents, but with the term, as thus used there, there are associated peculiar characteristics which do not manifest themselves in the torrents of other countries. “The sources of the torrents are hid in the recesses of the mountains, thence they descend to the valleys, on arriving in these they spread themselves out over an immensely extended convex bed, the convexity of which establishes a marked distinction between these torrents and most other water-courses, “Tn these the waters always flow in a hollow which encloses them in such a way that a section of the ground in a direction perpendicular to their course would give a curve concave towards heaven, the lower portion of which was occupied by the waters. In the torrents, on the contrary, when they reach the plain, a similar section would show a curve convex towards heaven, and the waters confining themselves in their course on the summit of this. With the water flowing in a slight depression on the summit of a convex torrent bed, it may be imagined that there can be but little stability in the current ; and such is the case. The most trifling rise or swelling of the torrent throws the water out of the depression, and it is scattered right and left, flowing away in streams which, however, still follow the line of the course of the bed. “ This instability renders the torrents very damaging, for they are ever breaking bounds at new points, and subjecting to their ravages immense areas of ground. Beds of torrents are to be seen exceeding 3000 métres, B 18 RESUMA OF SURELL’S STUDY OF or about two miles, in breadth. It never happens, indeed, that a torrent covers at any one time the entire surface of this; but in going now here, now there, it threatens continually every part of it, and after some floods every part may be found to bear traces of its passage. Such are the torrents when they debouch into the valleys. “ When they are traced up into the mountain passes they are seen to bury themselves in between steep cleft banks, which rise to the greatest heights, and thus form deep gorges. These banks, constantly undermined at the base, give way, and in their fall drag with them cultivated fields and adjoining dwellings. When this water-course is traced up to the sources of the torrents, the ground there is seen to be spread out like an amphitheatre. Tt forms a sort of funnel, open to the sky, which receives waters from the rains, from the snows, and from the thunder-storms, and precipitates them rapidly into the gorge.” By this gorge, as by the neck ofa funnel, the water is drawn off and precipitated into the water-course opening upon the let de déjection, or bed of deposit. In giving additional details of the principal peculiarities or characteristics of torrents, he says elsewhere, ‘‘ When one casts an eye over a map of the High Alps he- sees a country furrowed with innumerable water-courses, which are spread over the ground in a kind uf confusion. It is an aspect presented by all mountainous countries. Perhaps here the confusion is more manifest because of the little regularity in the arrangement of the mountain chains. These run in many different directions. They constantly cross each other’s lines, break into each other, and disturb the straight line of the valleys. From these frequent intersections results a certain disorder which has for a long time engaged the attention of geologists, but no satis- factory explanation of the production of which has been produced. All the larger water-courses flow into the Durance, the Buéch, and the Drac, whereby are formed three distinct basins marked out by these rivers.” In a note, it is mentioned that by one author, to whom I shall afterwards have occasion to refer—M. de Ladoucette, author of a work entitled Historie, Topographie, Antiquités, Usages, Dialects, des Hautes Alpes—there are reckoned five distinct basins; and by another, M. Hericart de Thury, there are reckoned eight; but the number might be increased indefinitely by considering every valley a basin. The three basins spoken of receive, he says, all the water-courses of the department with the exception of some insignificant streams which flow to the west. And he goes on to say, “ When the three rivers named are followed beyond the boundary of the department they all three are seen to discharge their waters into the Rhone, the first retaining its name to the confluence, the other two previously losing theirs. And thus it appears that all the water-courses of the department of the High Alps belong to the great basin of the Rhone, one of the five great basins of France. Each of the three basins is traversed by a great valley. which rises by insensible degrees to the col, or neck, in the mountain where it originates. It receives secondary valleys, into which descend other valleys smaller still, which may again be seen subdivided ina similar 7 oi see Pons like Nae, indefinitely subdivided, of whic. e secondary valleys are the branch i ‘inci Sebee Gained y y es, while the principal valley “All of these valleys, whatever be their comparative magnitude, their relative rank, or their position, are watered or drained by a stream Achioly indicates the thalweg or direction of the inclination of the valley ; and if we TORRENTS OF THE HIGH ALPS. 19 look horizontally across the sweep of this thalweg we see in most cases a curve, evidently continuous, the inclination of which rises,—or, if the expression be preferred, a curve the tangent of which, by degrees, approxi- mates the vertical as we approach the neck. : “The curve is convex towards the centre of the earth, and it may be remarked that the changes in the tangent are more rapid towards the neck than towards the base. In other words, the radii of the curve diminish in approaching the neck. “ This configuration,” says he, “is remarkable. Why should the bed of the water-courses be disposed in the form of a continuous curve? Why is this curve convex? Why does the curvature vary more rapidly above? The answer is—All these peculiarities are combined in the exact curve which best suits the flow of a liquid the volume of the current of which increases with the length of the distance gone over. And he asks,—Does it not seem that the forms which are so perfectly adapted to the laws regulating the movement of water can be themselves but consequences of these laws ? If it be supposed that the thalwegs have been brought into the state in which they are now seen by the same general cause, whatever it may have been, which created the mountains, why have they such regular forms, while the outlines of the summits, which, according to the hypothesis, would have been formed at the same time as they, show only capricious lines ? By what chance, in an infinitude of possible forms, have they taken exactly such an one as the waters would have themselves created had they not found it already made? It is in these circumstances reasonable to conclude that a regulated cause has operated in the formation of the thalwegs, whilst the summits have been left to themselves; and it is equally reasonable to attribute this to the action of the waters as the cause. “Tt is true that this supposition attributes to the waters a prodigious power, very different from the effects which they produce daily before our eyes, and therefore it is necessary fully to understand the manner in which they have been able to act in the formation of the curve of their bed, or in other words that of the thalweg. “When we trace attentively the course of the Durance it is seen that the valley successively expands and contracts in such a way as to produce a succession of basins separated by connecting straits. These basins are elongated in the line of the river’s course. The bottom of them is very level, and exhibits a clear and well-defined junction with the base of the enclosing mountain, giving to it an appearance suggestive of its having been in some measure reduced to level by water.” According to a generally received opinion, such elliptical basins are the basins, now filled up, of ancient lakes, and it may be that for a time the place of the river was occupied by a succession of such lakes or sheets of water appearing at different successive levels, communicating with each other by waterfalls or rapids, through which the waters then poured from the lakes, successively passing, as it were, from mill-race to mill-race. Little by little the beds or basins have been silted up, the rocks by which they were separated have been hollowed down, and the waters have at length come to flow in a united bed, and over continuous slopes. We have in our own day an example of such action in the consecutive lakes in the north of the United States, which seem destined to be lost one day in the River St Lawrence, and numerous illustrations of the same thing may be seen in Finland in all directions throughout the country. 20 RESUME OF BURELL’S STUDY OF There may be reckoned up on the Durance very distinct forms of five of these ancient lakes, extending from the neck of Mont-Genéve, where its source is, to the boundary of the department. Vestiges of the same phenomenon are to be seen in the valleys of the Grand Buéch, and of the Petit Buéch. They are to be seen, again, in the valley of the Drac, and in that of the Romanche. In general, all the great valleys of the department present similar traces. Some of these lakes existed within historical times, and we may remark, in fine, that the same appearances have been observed in a great many other places, and on all sorts of rivers. In this, then, we find a general mode of action, of which traces are constantly reproduced in a certain kind of valleys, to which may be attyri- buted not only the formation of the valleys but also the formation of their thalwegs, which two things are, he states, distinct and different. There are, he remarks, valleys which seem to have been created solely by the erosion effected by waters flowing at first in a simple depression in the soil ; other valleys seem to have originated in dislocations of the soil opening clefts into which the waters have afterwards precipitated themselves. But in valleys of both formations the action of the waters has invariably been the same, and it has produced the same results. Thrown upon an irregular surface of soil, they have followed at first the line of the greatest inclina- tion ; then they have modified this. Whilst this was going on there has been thus formed the most stable curve of the bed; under the double influence of the friction of the waters tending to reduction to a minimum, and the resistance offered by the soil tending to a maximum: this curve, thus formed, is the thalweg. Thus are brought together and harmonized a great many facts, the explanation of all of which are embodied in one formula—vague it may be— but unique, general, and of universal applicability. If the valleys be studied in their topographical aspect several laws may be discovered, covered by this regulated appearance, which seem to be entirely the result of chance. Amongst these are two beautiful laws evolved by Brisson, which may be verified here in most of the necks of the moun- tains. I adduce only one illustration of each. The first is supplied by the col of the Lauteret, situated between two water-courses, parallel and flowing in opposite directions—La Romanche and La Guisanne. The other is supplied by the col of the Bayard, situated in the district where the Drac and the Durance, after they have both flowed from east to west, separate,—the one directing its course towards the north, the other towards the south. A high- way which passes from the second basin into the first shows distinctly the thalweg passing by the col from the one into the other. By this notice of the action of water in flood we are prepared for entering upon the more special study of torrents. In the torrent, or what, in accordance with the English applicati that term, may be called the torrent-bed, there are slieaslie cee distinct parts,—the basin drained by the torrent or funnel-shaped hollow from which the waters are collected, called the bassin de réception ; the gorge and channel by which the waters are carried off from this: funnel- shaped basin, called the canal d’écoulement ; and the deposit of detritus at the lower extremity of this, called the lit de déjection. To this last great importance is attached, as by detritus borne down b torrents many fruitful fields have been buried under a layer of debrig under TORRENTS OF THE HIGH ALPS. 21 which they have been lost for ever; in view of this next in importance is reckoned the ravages committed by the flood in undermining enclosing banks, and thus bringing down fields and houses to be washed away and added to the deposit of debris; and M. Surell, after having traced the evil to its source, returns to treat of the several parts of the torrent in what would probably be considered by some of my readers an inverted order,— treating first of this bed of deposit, next of the channel, next of the basin drained, and next of the flood creating the torrent. I find it more convenient for my purpose to reverse somewhat the order in which I bring forward his views, following that which I have adopted in enumerating these different parts of the torrent. Looking at a bed of deposit, or lt de déjection, such as is often seen in the Alps, the question suggests itself,-Whence has come this detritus? Deep as may be the channel of the torrent, the canas d’écoulement, this alone could not have supplied such a mass of material as is generally found con- stituting a lit de déjection. A study of the outline and soil of the bassin de réception, or basin drained by the torrent, with the information previously obtained, supplies the information desired. This is generally more or less of a funnel-shaped basin ; the angle of inclination formed by its sides may be acute, very acute, or it may be obtuse, very obtuse,—but the resemblance to the sides of w funnel is marked ; the curve may be more or less irregular, and the arc may be more or less nearly complete, but there it is, more or less distinctly perceptible. Here we have discovered what may have been both cause and effect of what we have seen,—an effect of the rapid rush of water, a cause of the increased fall, and of the increased flow, and increased velocity of flow, and thus of the increased ravages and increased deposit and devasta- tion occasioned by the torrent ; and here we have found what may have been the quarry whence most of the material deposited at the outlet of the gorge may have been obtained. It is optional with any one to prosecute the enquiry thus suggested by himself alone, or to do so with the help of others who have gone over the ground before him. It isa matter to which Surell has given careful considera- tion. He has given as the result of his observations and thoughts that in order to the formation of these deposits there must have been in operation a great erosive force, acting on ground susceptible of erosion ; and seeing these meet in the flow of the torrent of water, and in the character of the soil over which it flows, he attributes all the phenomena to the meeting of a copious rainfall and a friable soil, so situated that a rapid flow of the water and a consequent erosion of soil must follow; and I have cited in detail his exposition of the whole contour of the region being attributable to some such aqueous operation. To follow him in his application to bassins de réception of the law thus evolved, it may be desirable to bear in mind that he speaks of three distinct forms of torrents, designated respectively torrents of the first, second, and third classes, The distinction is based entirely upon the position which their bassins de réception occupy in the mountains,—the first proceeding from a col or neck in the mountain range, the second from the mountain brow, the third from the mountain flank,—this difference of position to a great extent determining the differences seen in the aspect they present. In torrents of the first kind, in which everything appears on the largest 22 RESUME OF SURELL’S STUDY OF scale, the basin embraces vast ridges of mountains, and the outline may be traced on an ordinary map. The gullet is prolonged towards the lower art of the channel, forming a valley or rather a narrow gorge deeply embanked by the flanks of the mountains, and the length of which is often more than two leagues. It supplies, says Surell, the very best example I could give of valleys opened up or created by the action of the waters alone. In this gorge the hills are very abrupt, and minceo par les pieds, cut away at the base, and cut up by a great many ravines. They rise frequently more than 100 métres, or 335 feet, above the bed. At different distances they are cut into by secondary torrents, which are lost above in the rami- fications of the contour of the mountains, and they each bring into the gorge the waters collected from a part of the basin. These mountains furnish to the torrents a large portion of the matter carried away and deposited in the bed of dejection, and from their sides come the large blocks which fall here and there into the bed of the torrent. He mentions that in the bassins de réception, or basins drained by torrents, of the first order, there are often seen on the sides of the mountains enormous blocks of stone, which sometimes fall into the beds of the torrents and are then carried far by the rush of waters. In some cases there may be seen standing in a vertical position, in the middle of a slope, what looks like an artificial obelisk ; such are almost always capped by some such large block, which one would almost say had been placed there by the hand of man. It is to this block, says Surell, that the obelisk owes its formation. Originally the block lay on the surface of the slope. In this position, when there came a sudden heavy fall of rain, and the water was rushing away in little streamlets on the face of the mouutains, this stone presented a solid and indestructible obstacle which divided a current turning it off to the right and to the left. It may easily be conceived that in this manner it would protect the portion of the slope immediately beneath it, on which it rested ; this then would remain untouched and undisturbed, while the ground around it was being dug into and carried away. At last it would come to pass that the portion of the soil which had thus managed to keep itself above the level of the parts washed away, forming at first a ridge or a block of earth with a sharp angle, which became thinner and thinner by the action of time and atmospheric disintegrating influences, took the figure of a well-defined obelisk, standing out clearly from the slope. These obelisks are known by the inhabitants of the country under the designations demoiselles, or young ladies, and nonnes, or nuns. They may be seen on the mountains of the torrent of the ‘Graves, of that of Crevoux, of Rabioux, of Grenoble, of that near Briancon, etc., etc. The throat or gullet widens upward at the spot where it joins the funnel, and this sometimes takes the figure of a col denuded of its covering of earth, which assumes the form of an amphitheatre before the embouchure of the gullet. At other times the col forms what is called a pastoral mountain—a name given to mountains appropriated to the flocks—furrowed by innumerable currents, which there spread themselves out in the form of the foot of a goose. The torrents of Rabioux and of Mauriand may be taken as types of such, and so may the torrent of Bachelard, abutting on the col d’Allos, in the Lower Alps. These vast depressions being situated in the higher parts of the mountains, the water supply during the greater portion ‘of the year can only fall in the shape of snow. In this state it is not dispersed, or is but little dispersed ; it is retained, it accumulates, and if TORRENTS OF THE HIGH ALPS. 23 the warmth of spring supervene without a gradual preparation there is poured forth in the course of a few days the-mass of water accumulated during months. This may be considered one of the principal causes of the violence of certain floods. He cites the torrents which proceed from the Col Izoard towards Arvieux, to which reference has already been made, as presenting the most complete and perfect type of the gullet of a bassin de réception. There, as has been stated, more than sixty torrents, within less than 3000 métres, or two miles, precipitate into the depth of the gorge the debris torn from the two flanks of the mountain. In the torrents of the second kind the basin, instead of being cut out on the cols of the mountains, is formed by an indentation of their summits, and is hollowed out in their revers, It is in this kind of basin that it is easiest to trace the disposition to assume the funnel shape so characteristic of these basins, as the eye can take into one glance the entire course of the torrent, all the points of which are depicted before it. The torrent of Merdinal, at Saint-Crépin, may be cited as a type. Lastly, in the third kind the basin is reduced to a kind of large bog, hollowed out by some ravine, and which in the country often bears the name of combe, as for instance the Combes of Puy-Saniere, the torrent of Combe-Barre, the torrent of Comboye. It receives no affluents or feeders, and it collects little more, if any, than the waters which fall in the same enclosure as the depression. It is always dug out in the flanks of the mountains and below their summit; but it tends to grow, and it creeps up little by little towards the summit, which it reaches at. last. This process goes on with greater rapidity in grounds subject to rapid disintegration, and thus is formed in the long run many of the torrents of the second kind. And one can, in many cases, follow the progress and the different phases of the formation of these, from their nascent condition on to their complete development. Below the basin of reception, and in continuation of the gullet, is a region in which there is neither any more downfall of earth nor is there as yet any deposit. This is designated the canal découlement. Of the three parts of the torrent this is the least marked by characteristics, and almost alwayé the least extended. It is the longer the more gentle are the changes of inclina- tion in its bed And this is the reason why it is generally pretty lengthened in torrents of the first kind ; it becomes shorter in those of the second ; and lastly, in those of the third, it reduces itself almost to a vanishing point. The canal d écoulement is always contained between mountains well defined, In fact, when there are no mountains the slope does not suffice to prevent the torrent from spreading itself out; and in doing this it would lose velocity and it would cease to be. The canal @écoulement is the only part of the course in which the torrents do little damage. Unhappily it is the least extensive. It is here bridges should be located. If we could artificially prolong this channel to its confluence with the river, maintaining throughout its slope, its section, and its course, we would stop the ravages. And this is the problem in the embankment of torrents, The its de déjections, or beds of deposit, at the mouth of the torrent next demand attention. The aspect of many of these is suggestive at first sight 24 RESUME OF SURELL'S STUDY OF of a vast ruin, and several torrents have obtained their names from a per- ception of this resemblance. Thus is it with the torrent dela Ruine, at Lantaret, the torrent de la Ruinasse, at Monestier, and the torrent de Ruinance, on the Lower Alps. The deposit is a heap of pebbles and of blocks of stones, scattered over a vast extent of ground—an arid region devoid of culture, of vegetation, and even of vegetable soil—and it suggests to the mind the idea of some great catastrophe having occurred. In sight of this enormous mass of debris, one finds it difficult to perceive or admit that it can be the work of the paltry thread of water—a mere streamlet—which is seen oozing through among the rocks. Examined more carefully, it is seen that these heaps, which seem scattered there in so much disorder, are disposed in accordance with mathematical laws. The general outline of elevation is that of a very much flattened hillock ; the outline of shape is that of a half-expanded fan extending from the mouth of the gorge and leaning on the mountain like a buttress. Projecting lines, which mark on the surface of this cone the lines of greatest declination, are arranged very regularly, following the gentle slopes, which bend inwards a little towards the bottom, but maintain withal a perfect continuity,—all taking their departure from the mouth of the gorge forming the apex of the cone. Further on they diverge somewhat further horizontally, with an outline so distinct that if made with a ruler it could scarcely have been more so, and thus is completed the resemblance first suggested—that of an expanded fan, the joint of which is represented by the mouth of the gorge, and the scales of the fan by these rays, somewhat raised towards the middle, as is the back of an ass, and presenting an appearance such as may be supposed to have been produced by the natural slope of a semi-fluid or viscous body flowing out of the mountain and escaping by the gorge. The whole aspect of the mound is so peculiar that it reveals from a great distance the existence of a torrent before any other indication has been seen to awaken a suspicion that such may be there. It stretches often more than three-quarters of a league in breadth, and its height above the level of the valley may exceed 70 métres, or 230 feet. Nothing can better prove the force of these torrents in action than those immense deposits formed entirely of what has been ejected by them. When one looks, says M. Surell, at the slope presented by these beds of deposits at the water level, following with the eye the central ridge of the cone-shaped group of these, he may perceive them to manifest the following three laws, which may be seen regulating the deposit beds of all torrents reproducing the same or similar effects everywhere with the greatest con- stancy :—(1) The longitudinal profile forms a continuous curve convex towards the centre of the earth,—that is to say, to express the fact in other terms, that the slope becomes less, diminishing in proportion as it goes down towards the river; (2) The changes in the declivity of the fall are more rapid towards the top than towards the bottom ; (3) The declivity of the fall, or slope, varies with the nature of the deposits. It is never under 2 centimétres per métre, nor above 8 centimétres—2 and 8 in the 100; and it is constant for all the torrents of the same locality, and which have their origin in the same mountain range. It is then shown by the author that that curve is the natural result of the action of the flood; and he proceeds to discuss the causes and the con- sequences of the formation of these beds of debris deposited by them. TORRENTS OF THE HIGH ALPS. 25 Two distinct causes concur in the formation of these deposits. First, the torrents proceeding from a confined channel in the mountain come into a valley, in which, being all at once deprived of the side support of sustaining banks, they diffuse themselves, losing velocity and depth. And then the passing from the steep declivity of the mountain to the gentle declivity of the plain proves a second and an additional cause of loss of velocity and of depth. The two causes are distinct and altogether independent of each other, and importance is attached to this circumstance. The tendency is to form a continuous curve from the canal découlement, corresponding to the angle of stability. Where this has been done the first cause alone will make additions to the bed. Where this limit of slope has not been created deposits will be continued in virtue of the operation of the second cause. From which it follows that some torrents may be confined by artificial structures, but not others; and that in the former case, other things being equal, the effects will be probable in proportion as the diminished slope may be continuous with that from the gorge, as this continuity is a presump- tive proof that the curve of the bed has been definitely taken to such an extent that the dejected matters have reached the limit of their slope, which is to them in the circumstances the angle of stability. Detailed information is given in regard to the effect of the current in giving to the bed of déjection its peculiar form, with such variations as have been noted, and in regard to the effect of this upon the current. There are next described the materials brought down by torrents—clay, gravel, shingle, and blocks of stone. The laws regulating the deposit of these are noticed ; and the injuries which are thus done are detailed. Every thing connected with the phenomena of the bassin de réception, the canal d’écoulement, and the lit de déjection, having been discussed, attention is given to the phenomena of the flood of water by which the damage and devastation are occasioned. This he traces to two sources—first, the ‘melting of snow towards the beginning of June, and second, storms of rain occurring towards the end of summer. Those occasioned by the latter are by far the most awful, and by far the most injurious In general, says he, the rain of such a storm gives rise to a much more terrible swelling of the torrents than does the melting of the snow. Rains are rare in these mountains ; but when they do fall they fall in tremendous showers, like waterspouts. Their action is instantaneous and cannot be foreseen. The snows never melt so suddenly and quickly as come the deluges of rain, and they produce more prolonged but less sudden swellings of the torrents. Besides this, they may be foreseen and anticipated, for ‘they come at known times. The torrent de Ascension owes its pame to the regularity with which it flows about the time of Ascension day. And the melting of the snows produces a general swelling of the torrents and rivers, which causes all to overflow at the sametime. The swellings caused by storms of rain are local ; one torrent becomes furious, while another quite near to it remains dry. The time of the melting of the snow is that for the highest floods in all the water-courses in all the department ; and for all, without exception, the time for low-water is towards the end of autumn. The phenomena which accompany the swelling of torrents are very varied. It may be said that each torrent in its manner of flooding has something which is peculiar to itself, and which is not found in any of the others. It must be so, for all the torrents have not the same distribution of slopes; 26 RESUME OF SURELL’S STUDY OF and the same thing may be observed in all rivers, each of which has a character of its own. Sometimes the swelling occurs gradually ; the waters rise ; clear at first, they become more and more turbid, and then throwing their strength into their velocity, rolling along stones which strike each other with a dull sound, they end at last by overflowing their banks, and then begin the ravages and additions to the deposit in the bed de déjection. At other times they come suddenly, and all at once is seen instead of water the black lava-like flow of stones, the slow progression of which has nothing like to the flow of liquid. ~ At other times, again, we find the torrent falls like thunder. It is announced by a rumbling roar in the interior of the mountain range, and at the same time a furious wind escapes from the gorge. These are the precursory signs. In a few instants the torrent appears in the form of an avalanche of water, rolling before it a heaped-up mass of blocks of stones. This enormous mass forms a moving barrier, and such is the violence of the impulse that the stones may be seen leaping before the waters become visible. The hurricane which precedes the torrent is accompanied by effects still more surprising. It makes stones fly in the midst of a whirlpool of dust ; and there have been seen sometimes on the surface of a dry bed blocks moving as if propelled by some supernatural force. \. All these statements, incredible as they may appear, are attested by a host of cases. I quote some of these, but I shall afterwards have occasion again to call attention to the subject. “Tn 1837 several carriers, and at the same time a Conductuer des Ponts et Chaussées, were stopped during a storra at the place where the torrent La Couche crosses the highway, No. 94. The torrent was then dry. All at once a whirlpool of dust descended along the river-bed, and before their eyes some lumps of stone cleared the road at a bound. “Tn 1821 the roadway of the bridge at Boscodon was swept away by a blast of wind coming with fury from the gorge of the torrent. Immediately the waters arrived, tearing along between the abutments of the dismantled bridge. This event occurred within ten minutes after the Prefect of the Department had passed, and under the eyes of a great number of country people engaged in harvest work in the field above. The Prefect, question- ing the fact, caused several of these people to appear before him, when he questioned them, and held'a kind of formal inquiry, which established all the details which have been reported. “At Guillestre, in 1836, there was a frightful overflow of the stream Rif-Bel, which flows through the middle of the market-town. Several persons were standing near a bridge, listening to the noise made in the mountain, when an enormous stone was, without apparent cause, thrown te their feet, more than 4 métres, 13 feet, above the bed of the stream. “The torrent of the Moulettes, which threatens the market-town of Chorges, overflows every year, and it gives every time an opportunity of verifying facts of the kind stated. In July 1838, a little rain having fallen on the summits of the mountain, this drew some of the inhabitants on to the embankment to see the torrent. Soon the blast of wind—the avant- courier of what was coming—made the stones roll with such violence that all these people, drawn thither by curiosity, drew back in haste. In a moment the embankment which they had just quitted fell down as it were so to speak, under their heels. It was a massive wall built of stone and TORRENTS OF THE HIGH ALPS. 27 lime, 2 métres or nearly 7 feet thick, and 5 métres or 17 feet in height. The breach, extending 25 métres or 83 feet in length, fell with a crash which was heard more than 3000 métres or 2 miles off. It raised a cloud of dust through which was seen the lava-like stream making straight for the town.” Another case, which shows how sudden these irruptions are, was this :— “Tn 1837 the village des Crottes was encroached upon by a small torrent of the third kind, which no one had ever feared. In an instant the cellars and the tortuous streets of the village were inundated with mud and blocks of stone. A great many cattle were smothered. With difficulty many people escaped with life, and a child perished in a stable.” The following additional facts, relative to the avalanche form taken by the torrents, are given :—“ At the bridge over the little torrent-stream of Chaumateron, in June 1838, the road-labourer heard the precursory sound. Aware of the danger he moved away. He had gone but a step or two when he saw coming the torrent tumbling over itself. It threw itself in one mass over the bridge and broke it. The elevation of the roadway of the bridge above the radier plate was 5 métres or 17 feet. “The village of Saint-Chaffrey is traversed by a small torrent. The bassin de réception is hollowed out of a bed of gypsum. It flows over a steep declivity at the foot of solid banks, but not very high. At every rise or swelling of the torrent it comes tumbling over itself like a ball, 8 métres or 25 feet in height, and a portion of the hemisphere appears above the banks. It is formed of liquid thickened with gypsum, and brings in its train a great current of water, which tears along with violence, but following ordinary laws. With these examples (says he) I stop. They might be multiplied indefinitely, for they are renewed every year.” My purpose in citing these details is, first, to make my readers acquainted with the facts stated ; next, to give confidence in the man who could bravely grapple with the question,—How shall such torrents be bridled and tamed ? and beyond this, to give confidence in the application, to what may be con- sidered as the torrents of a mill-lead in comparison with these, of measures deemed, and proved by recorded results, to be sufficient to prevent so much as the formation of torrents so irresistible in their might as these. To this I have referred in the introduction, and I refer to it again. My fear, as stated then, is that to many the statements will appear incredible, and that thus the end and object I have in view will fail to be accomplished. Statements of fact, far surpassing what may have come under the experience or observation of a reader, may arouse suspicion in regard to much besides what may be stated in connection with what thus startles, and may call forth resistance to the truth advanced. The rise of such incredulity may perhaps be prevented, if I shew that these statements are in accordance with what has been stated by others of what has come under their observation else- where. To those who are conversant with the literature of the subject there is nothing startling in such statements. Theories may be questioned, but the facts are accepted. I shall afterwards have occasion to cite at some length the statements made by M. de Mardigny in a Mémoire sur les Inondations des Rivieres de VArdéche ; here I cite only one. Of the tributaries of the Ardéche he tells that they often hurl into the bed of that river “‘enormous blocks of rock, which this river in its turn bears onwards and grinds down at high-water, so that its current rolls only gravel at its confluence with the Rhone.” 98 RESUME OF SURELL’S STUDY OF The expression “enormous blocks of rock” may seem vague; I can be more explicit. Coaz reports that at Renkenberg, on the right bank of the Vorder Rhein, in the flood of 1868, a block of stone, computed to weigh nearly 9000 ewt., was carried bodily forwards—not rolled—by a torrent a distance of three quarters of a mile. Coaz, Die Hochwasser im 1868, p. 54, cited by Marsh, by whom also is cited the following statement from Die Oecsterreichischen Alpenlinder und ihre Forste, by Joseph Wessley, a work published in Vienna in 1853 :—* The terrific roar, the thunder of the raging torrents, proceeds principally from the stones which are rolled along in the bed of the stream. This movement is attended with such powerful attri- tion that, in the Southern Alps, the atmosphere of valleys where the lime- stone contains bitumen has, at the time of floods, the marked bituminous smell produced by rubbing pieces of such limestone together.” Occasionally it happens that after a temporary suspension of the flow, the torrent of water, and mud, and stones, burst forth afresh. These explosive gushes of mud and rock appear to be occasioned by the caving-in of large masses of earth from the banks of the torrents, which dam up the stream, and check its flow until it has acquired volume enough to burst the barrier, and carry all before it. In 1827, such a sudden irruption of a torrent, after the current had appeared to have ceased, swept off forty-two houses, and drowned twenty-eight persons in the village of Goncelin, near Grenoble, and buried with rubbish a great part of the remainder of the village. From these statements it will be seen that similar phenomena have occurred elsewhere ; and we may thus be prepared to follow Surell in his study of the phenomena reported by him. “There are,” says he, “in these irruptions an action like to that of the avalanches. The inhabitants of the district designate them by this term ; it is not a mere figure of speech ; there is in reality an identity of cause, as there is a similitude in the effects. When a great mass of water suddenly pours into the gullet of a bassin de réception, resting on a very steep slope, and confined in a deep gorge, this mass no longer flows in accordance with the peaceful rules of hydrostatics. It rises behind to a great height, rolls over on itself, and thus descends the gorge with tremendous rapidity—far beyond that of the regular current of water which is flowing before it towards the bottom. It must then overtake in succession all the points of that current; it absorbs all its waters, which it hurries along with itself, and which it assimilates to its own mass. In this course its volume swells in proportion to the distance traversed, and when it debouches in the valley it arrives charged with the whole mass of water which was contained in the bed of the torrent from its birth to its exit from the gorge. It is in reality the whole mass of the torrent heaped up and concentrated simultaneously in a single wave. This phenomenon is identically that of the avalanche, with only this difference, that the water, fluid in the first case, is in the atate of snow in the second. By this explanation may be understood the short duration of certain floods,—for instance, an hour after the catastrophe at the bridge of Chaumateron, mentioned above, the bed was dry as it was before “ Another fact, not less singular, is that of the hurricane which precedes the torrent. Let us try also to explain this. All the examples of a hurri- cane which I have been able to collect relate to those floods following storms of rain during the close heats of summer, Let us suppose that in one of those sultry days, so common at this season in this part of the Alps a thunder-shower, storm of rain, or water-spout falls on the bassin de réception ; TORRENTS OF THE HIGH ALPS. 29 there is immediately poured a great mass of cold air over the whole extent of this region. This, specifically heavier than the rest of the atmosphere, can neither rise nor spread out, because it is imprisoned in a kind of funnel, which constitutes always the form of the basin. It escapes then by the gorge, following the line of greatest declivity, as every fluid must, and is precipitated to the bottom of the medium of lesser density. The phenomena of this efflux becomes in every respect similar to that of water. “But there are causes which must prodigiously accelerate the velocity. The column of water carries with it a great volume of air incorporated with it, which it pours with violence into the gullet. At the same time it does not cease to press with all its weight on the volume of air, which has been engulfed in the gorge as in a closed channel. There is there, then, a double action, the force of which is extreme ; one may form some idea of it by com- paring it to that exercised by the trombes d'eau, which serve as blast-engines to the works established in the mountains. It is necessary to imagine the air escaping by the gorge of the mountains as by the nozzle of the bellows of a gigantic forge, and then there will be no wonder that it produces the effects I have described, which are all the consequences of excessive rapidity.” This may require some explanation or illustration, Marsh, citing Wanderungen durch Silicien und die Levant, by G. Parthey, a work published in Berlin in 1834, gives the following singular instance of unforeseen mischief, following from an interference with natural arrange- ments, which may be considered a natural illustration of the application of force referred to by Surell in his allusion to the application to blast- furnaces of what is called a trombe d@eau:—“ A land-owner at Malta possessed a rocky plateau sloping gradually towards the sea, and terminating in a precipice forty or fifty feet high, through natural openings in which the sea water flowed into a large cave under the rock. The proprietor attempted to establish salt-works on the surface, and cut shallow pools in the rock for the evaporation of the water. In order to fill the salt-pans more readily he sank a well down to the ocean beneath, through which he drew up water by a windlass and buckets. The speculation proved a failure, because the water filtered through the porous bottoms of the pans leaving little salt behind. But this was a small evil compared with other destructive consequences which followed. When the sea was driven into the cave by violent west or north-west winds it shot a jet d’eaw through the well to the height of sixty feet, the spray of which was scattered far and wide over the neighbouring gardens, and blasted the crops. The well was now closed with stones, but the next winter’s storm hurled them out again, and spread the salt spray over the grounds in the vicinity as before. Repeated attempts were made to stop the orifice, but at the time of Parthey’s visit the sea had thrice burst through, and it was feared the evil was without remedy.” Something similar to this is the action referred to by Surell. The analogy holds only in the compression of air by the pressure of water following upon it quicker than it can escape, and the force developed by its elasticity where space is found for its subsequent expansion. M. Surell enters into several computations to determine the rapidity of the flow of torrents, from which it appears that while the flow of the most rapid rivers does not exceed 4 métres, or 13 feet, per second, both calcula- tions and observations shew the flow of these torrents to be sometimes about 14:21 métres per second—nearly 15 métres, or 50 feet,—which ig the 30 RESUME OF SURELL’S STUDY OF velocity of a strong wind. Applying this to a torrent through 4 canal 8 métres, or 27 feet in breadth, and 2 métres, nearly 7 feet in depth, he shews that it gives a flow of 228-48 cubic métres per second, while the Garonne gives only a flow, in the ordinary state of the river, of 150 cubic métres, and the Seine of 130 cubic métres, per second ; and thus is the brief duration of the flow of a torrent accounted for. The calculation is founded on a formula given in D’Aubuisson Hydraul—(p. 133), in which, representing the fall per métre by p, the section of the body of water by s, the perimetre mouille, or circumference of the wheel, by c, the velocity =51 square P 8 +¢. It is founded on the observation that in such rapid currents the resistance to the flow is proportional to the square of the velocity ; and extencing the computations to determine the size of blocks of stones which may be carried down by such torrents, he shews that such a torrent as is supposed is capable of moving a stone of the heaviest kind equivalent to a cube of 5°15 métres. But referring to the circumstance that a torrent 2 métres, or 7 feet in depth, could not act on such a block over the whole of its side, he shews that this will give only an equivalent of 2°74 cubic métres ; and then he states that, in accordance with this, it is not rare to find blocks of 20 cubic métres near slopes of 6 centimétres per métre ; and that in the last preceding irrup- tion of the torrent of Chorges the waters left on the bed de déjection a hundred blocks of 30 cubic métres, and some even which measured upwards of 60 cubic métres. Section IL—Watural History of Torrents in the High Alps. The most striking and characteristic feature of torrents—understanding by that term what in English would be called the bed of the torrent—is, according to M. Surell, the deposit known technically as the lit de déjection, though this can only be considered a product of the flow of water by which that bed of the torrents is produced, for, if the waters had not carried off the material deposited, then there could have been no deposit; and by this are supplied indications of the comparative age or antiquity of many torrents now extinct. Often, says M. Surell, are we struck, in passing through the department, with the appearance of a flattened mound, situated at the opening of a gorge, presenting a fan-shaped surface with very regular slopes,—it is the bed de déjection of an ancient torrent. “Sometimes careful continued observation is requisite to the discernment of the original form, concealed as this is by massive trees, by cultivated fields, and often even by houses and towns. But when it is examined with care, and looked at under different aspects, the outline so characteristic of beds de déjection comes out at last most clearly, and it becomes impossible to mistake it. Along this mound flows a little streamlet which proceeds from the gorge, and peacefully traverses the fields. It is this which has ormed the ancient torrent, and in the depth of the mountain may be dis- covered the old basin de réception, recognisable also by its form. “ These extinct torrents, if such a phrase muy be used, are More numerous than one at first thought would expect. When once the key to be employed in the search has been obtained, and attention is directed to them, creat numbers are discovered, ni TORRENTS OF THE HIGH ALPS. 31 “The site of the market town of Savines may be adduced, amongst others, ag a very remarkable example of this kind of formation. The whole town, along with a part of its fields, stands on a bed of ejected deposit, the breadth of which exceeds 1500 métres, upwards of a mile, covering fields once of great fertility. The nature of this ground is no more doubtful than is its origin. It has been excavated to its greatest depth in digging foundations and in sinking several of the wells in the town ; and the drains of a highway lately put in order have disembowelled it in all directions. Below that town the Durance has cut out a channel and bed on some banks more than 70 feet in height, which forms a sort of natural cutting across the bed. It surmounts and overlooks the whole place, and towards the west, at the extremity of the town, there flows the stream by which all the deposits have been produced ; this is confined between high banks adorned with meadows, and flows deep down in its own earlier alluvial deposits. “Tt is thus open to the day on all sides, and may be studied with the greatest ease. Everywhere it is composed of rolled stones, agglutinated by a lime-like mud. This pudding-like matter is spread in regular beds parallel to the curvature of the surface. It becomes harder and coarser as we get further down, and ends in forming a very compact mass. As to the characteristic form, it may be distinguished from a distance, especially on the east side. The town is built on the highest portion, and the fields lie scat- tered around it. In the background rises the mountain, Le Morgon, in which the basin of reception is covered or buried now under black forests of firs. “It may be remarked that the extinction of this torrent, although of a very old date—dating as it does from a time beyond the memory of man —must nevertheless have occurred after the first establishment of human habitations in this mountain range, for hearth-stones and lumps of charcoal have been disinterred from great depths in the pudding-like mass. These fragments show that men had been then in the locality while, anterior to historical times, the torrent in full action was making this bed of deposit ; and the name of the stream seems to indicate that the stream must have retained its violent character till times less remote from our own.” In a note it is stated it is called Branafet, which seems to be a corruption of Bramafam, Howling Hunger, a name already mentioned as common to many torrents; and it seems as if in losing its violence it had lost also the name which spoke of it. “The details mentioned leave no doubt in regard either to the fact or to the interpretation put upon it; and they are applicable, not to a single isolated case, but to an order of things which is quite general, the examples of which are widespread, and would each of them furnish materials for observations precisely similar. Names are given in a note of several, with references to more. It must therefore be admitted as an established fact, that the violence of torrents is not of interminable duration, but that it may be arrested—be it by the accomplishment of a definite effect, or be it that the torrent has been brought under some influence by which it has been stifled. “The torrents which present these features are probably the most ancient. To render this conjecture more probable, I proceed by a bound to the opposite end of the scale. We find villages standing in the place where torrents in full action debouch from the mountains. Thus is it with Les Crottes, and with the market-town of Chorges. It is most probable that these towns were built where they stand before the torrents by which they 32 RESUME OF SURELL’S STUDY OF are now threatened made their appearance ; for, on the one hand, these towns are very ancient—Chorges, for instance, dates certainly from before the commencement of the Christian era ; on the other hand, the two torrents which now severally threaten these towns cannot have acted long with the energy which they at present manifest. Their slope is abruptly broken at the issue of the gorge ; their bed of dejection is not yet regularly formed, and that of Chorges has risen 6 métres, or 20 feet, in the course of the last fifteen years. “Tf this process had been going on at the same rate for only a thousand years the market-town would have been buried long ago under a mountain of deposit. That of Crottes, again, is a large ravine, which has only within the last few years given occasion for disquietude. There are cases yet more conclusive in regard to the comparatively recent formation of some torrents which can be adduced. A church in the valley of Dévoluy is threatened by a torrent which flows directly towards the building, and is only kept in check by an embankment constructed about twenty years ago; and we cannot suppose such an edifice, the construction of which seems to have been attended to with all care, to have been erected in the very mouth of the torrent! The style of its ornamentation is that of the beginning of the thirteenth century. We know well with what precautions Christian archi- tects have surrounded their edifices, and we infer that this torrent did not exist when this church was built in the thirteenth century, and if so there have been torrents formed in historic times. And, without quitting this same district of the Dévoluy, we can cite examples of formations of a still more recent time. In this district completely organized torrents have been developed under the eyes of the population of the present day. Several have not yet even received names, and they commit already fearful ravages. “In travelling through other localities like observations may be made. Recent torrents are ploughing out for themselves their courses on all hands. Everywhere new cases are surging up, which prove the abundance and the rapidity of these formations ; and one is soon brought to a stand in con- sternation before this accumulation of facts, which present a bad omen for the future of the country.” In a note it is added,—“ Immediately in front of the esplanade of Embrun is seen a mountain cut by a number of torrents of the third kind. They grow, so to speak, under the very eyes of the town. One of them, called Piolet (petit lit), which was only a little ravine about thirty years ago, when it received this name, has become a large and perfect torrent. The mountain, which extends from Orciéres to the valley of Champoléon, on the right bank of the Drac, is being ravaged by such a number of torrents that it seems as if it must be swallowed up in a mass by the river. These torrents are for the most part recent, and the old men of the country have seen them born, and seen them develope themselves to their present magnitude.” “Thus does it appear that torrents may be formed in our own day ; several are of an age quite recent, and besides these, as if not to leave a single link in the chain of ages awanting, there are torrents existing which, judging by their form, their appearance, and their effects, may be placed as inter- mediate in age between the extinct torrents, and the torrents still in full activity. These are not yet confined within a stable course in the middle of the deposits ; but they overflow-only a small part of their bed. The rest is covered with cultivated spots, woods, and houses, and seems to have been TORRENTS OF THE HIGH ALPS, 33 abandoned by the torrent from time immemorial. And torrents in all stages of the transition, which begins in the establishment of the extreme limit of the slope, and ends in complete extinction, are met with. Stability begins, generally, first to show itself towards the extremities of the bed, and vegetation establishes itself there, advances, and ends in invading the whole surface of the deposit.” Names of several torrents, illustrating what is said, are given. These observed facts are followed up by M. Surell with reflections on the age of the torrents themselves. Specifying and detailing the peculiar charac- teristics of three recognised forms of torrents, and generalizing the whole, he concludes,—‘‘ The action of torrents may thus be divided into three periods, corresponding to three different ages of growth and development and having each an end to accomplish, and distinct effects which they severally produce. ‘“‘ The first period embraces the creation of the curve or general sweep of the bed of the torrent. “In the second period the curve or sweep is determined, created, fixed, but the course or channel is not yet fixed ; and it is changec from time to time as if by accident, but all in accordance with law. “Finally, the third period is that of a stable régime. The course or channel as well as the curve is permanent, or as permanent as manhood is in comparison with childhood and youth. “But many things remain yet to be explained. “ Why do extinct torrents, when they are confined within banks of their own deposits, plough up the very slopes over which they themselves immediately before flowed without having strength to scoop out of it a bed for themselves? The reason is a very simple one. In proportion as the torrent was becoming extinct the waters became more and more limpid. They took then on the same slopes a greater velocity than that which they had when they came charged with alluvial matter, and they then could scoop out where they had previously been depositing. “By what cause, again, are new torrents produced? One cannot at all see why waters which have respected a district during long ages should begin to attack such district now, if all things continue as they were. Those causes which operate to produce a new torrent ought to have formed it from the first day of the creation of the mountains. How could the district of itself change its form or nature ? “Tt is evident that foreign influences must have interfered, which have modified the primitive conditions. ‘We are thus brought into contact with a new order of facts which demand attention.” It is then stated that when we examine grounds, in the midst of which are torrents of recent origin, we find them always devoid of trees and of every kind of robust vegetation; and when, in some other localities, we look to revers, the sides of which have been recently deforested, we see them to be cut bya great many torrents of the third class, which aparently could only have been formed within a few years before; and extended observations bring under consideration a great many corresponding facts. _ “There exist many revers formed by the detritus of the vertical rocks which generally crown the summits of the mountains. In these mobile soils vegetation takes root with power, and vigorous forests of larch and firs have clothed the sides of the mountains. But the axe, little by little, has deci- mated the trees ; the fellings, made without plan, have opened across the forest large open spaces running with the slope of the revers, this arrange- Cc 34 RESUMA OP BURELL'S STUDY OF ment being that which renders exploitation most easy. Now, wherever the woods have been cleared in this manner, at the place of each clearance the vegetable soil has been carried away by the waters; a furrow is formed there, of little depth at first, but which digs away more and more, extends itself upwards, enlarges itself, and soon constitutes a complete torrent, In the intermediate stripes, where the trees have been spared, it is seen to be altogether different. There—with the same soil, under the same exposure, under the same slope, and this often very steep,—the ground has been held firm, and the contour has been respected by the waters. In going over the forest we often traverse thus a succession of zones, the differences of which are striking. We may even catch sight of intermediate shades, which fill up the contrast. We see nascent ravines in parts where the stumps thickly standing bear testimony to a recent destruction of trees. We see completed torrents in other parts, where the indications of the ground, and the inform- ation given by the inhabitants, bear testimony to trees having been destroyed in times more remote. We are thus well assured that we are not taking the effect for the cause, when we affirm that it is the destruction of trees in the clearance which has formed the ravine, and not the ravine which has formed the clearance.” As is the case with the gorges, so does it appear to be the case with the bassins de réception. There is no question in regard to the fact that the effect of such a conformation of the basin drained by a torrent, as has been described, is to bring a large body of water, falling over a great extent of surface, to concentre in the orifice of the gorge ; but the allegation of Surell is that the form of the basin is itself the product of the long-continued violent action of waters, collected first in a recess of the mountains, and flowing over a soil of little compactness and cohesion ; and he accounts for the absence elsewhere of certain characteristics of the torrents of the High Alps by stating that, where the ground presents more resistance, and where the climate is less rigorous, there may be formed only brooklets and moun- tain streams. Similar torrents are not met with in the Vosges, in the Cévennes, or in the Auvergne. In the Lozére there are vallats which are not without characteristic features of torrents of the third class, such as are of frequent occurrence between Briangon and the Monestier, and along the Guissanne ; but these, through their weakness, scarcely resemble true tor- rents, though, compared with vallats, they are torrents of great energy. The torrents of the Pyrenees, generally called Gaves in the district, are very rapid water-courses in deep cuttings, often losing themselves in sub- terraneous canals, but they should be classed with mountain streams or torrential rivers. And no torrents are met with in the mountains of La Corse, or in those of the Jura, But torrents similar to those of the High Alps are found in a portion of the mountains of the department of the Isére of the Dréme, and of the Lower Alps, which belong to the same formation. A chapter is devoted to the consideration of cli influence, and another to the effects attributable t+ geological formations of the locality. In regard to climate, he shows that the elevation them into the region of snow. When this accumulates all winter over an extensive area, and under the powerful rays of spring melts in great quanti- ties all at once, the process being often accelerated by the arrival of warm matal or atmospheric o the character of the of the High Alps brings TORRENTS OF THE HIGH ALPS, 35 southerly winds, so much so that sometimes in two days’ time the breaking up is finished and the whole of the snow has disappeared, this is one powerful cause of disintegration more energetic there than elsewhere ; but it is trifling compared with others,—in illustration of which he refers to the clear blue sky of the High Alps, a district in which fogs, and mists, and long-continued drizzling rains are unknown, though these are throughout a great extent of France the normal characteristics of the atmosphere during six months of the year. ‘ Nothing,” says he, “ can equal the purity of the air, the unchanging serenity of the heavens, there. But this dryness of the air and this cloudless sky are dearly purchased, for the rains, if less frequent, are the more tremendous.” M. Dugied, author of a Memoire entitled Projet de boisement des Basses Alpes, to which I shall afterwards have occasion to refer more in detail, says, in writing of this,— It is thus that it comes to pass that the Alps are sometimes months, sometimes years, without rain. Then all at once the clouds gather as if from all points of the horizon, pile themselves up as if pressed by opposing winds, and empty themselves in torrents which sweep * away everything in their course.” M. Surell says,—“ It is an admited fact that the quantity of water which falls annually in a mountainous country—other things being equal—is greater than in the country of the plains. It is also an admitted fact that the quantity is augmented as we approach the tropics. It follows that there ought to fall here a quantity of rain equal at least to what falls in the same time in Paris. But while the fall in Paris is distributed over a period of six months, here the whole quantity is used up in some few rain-storms.” This makes all the difference ; and thus, to some extent, is the soil made more mobile than it is elsewhere, and of this the following illustration is ven :— ae There is a transition point very remarkable where the climate changes all at once from that of Provence to that of the north; it is the col du Laterat. In proportion as we rise towards this neck, in ascending the valley of the Durance, and then that of the Guisanne, its affluent, we see the serenity of the heaven disturbed, and rainy days become more and more frequent. When the neck is passed, and we penetrate into the gorge of Mallaval, dug out by the Romanche, in following this water-course into the country called the Oysan, which is a portion of the department of Isére, there the change of climate is complete. The rains are extremely frequent, and instead of falling in what seem like thunder-plumps they are prolonged, and fall continuously as drizzling rain. The air is almost constantly moist, and loaded with clouds. One sees the mists creeping over the sides of the mountains, to catch upon the projecting rocks, and often to envelope the valley completely. In a word, we have entered the climate of the north, the same as prevails at Grenoble, and which differs in a striking manner from that of Embrun, where fogs are a phenomenon almost unknown. “From this difference in the climate follow corresponding differences in the action of torrents. The mountains which enclose the valley of the Romanche present in many parts the same kind of ground as do those of the basin of Embrun; it is a flaky, black, calcareous earth, remarkable for its excessive friability. But this same soil, which in the Embrunais is furrowed by a multitude of formidable torrents, shows in the Oysans only a few torrents, almost effaced, without energy, and in no repect to be compared with those, In the latter country the mountains are seen clothed on the steepest slopes 36 RESUME OF SURELL’S STUDY OF and covered with vegetation over all their height ; and although they may be stripped of trees, they are scarcely furrowed by a few thread-like streams. In the Embrunais, on the contrary, where the forests have disappeared from the sides of the mountain, these never fail to become the prey of the torrents. “ Such is the hygrometric action of the climate. There, where the soil is constantly bathed in a humid atmosphere, the summits carpet themselves with verdure, and the torrents have no more aliment. Here, where the air is always dry, vegetation proceeds with more difficulty, and the storms of rain sweep from the surface the soil to the extent to which vegetation has fixed it there. “Thus the moisture of the climate impedes the action of torrents in two ways equally effective ; first, it makes the rain storms more rare and less violent ; secondly, it renders the soil more fixed by covering it with more vigorous vegetation ; it diminishes thus as by one stroke two causes of erosion. “Tf there still remain any doubt as to the active part played by the climate in the production of torrents, I would cite a general observation which has been made for a long time in these mountains :—When one traverses the valleys running east and west, or the reverse, he sees that the slopes on the north side are generally wooded, or carpeted with vegetation, whilst those which look towards the south are denuded and arid. He sees, at the same time, that the former are much less cut up with torrents than the latter ; and the contrast is often such that he sees the one slope horribly disfigured by torrents over against another on which there exists not one, as, for instance, in the valley of Orcieres, in the Vallonise. “ Now it is evident that such a difference in the whole character of two slopes, which are almost always formed of the same banks of earth, cannot be explained but by the influence of the exposure. And how does the exposure act but by moderating in the slopes directed to the north the effects of the noon-tide sun? They protect for a longer time the snow, retain more humidity, are protected from the scorching winds of the south, enjoy all the advantages of shade and coolness, d&c. All these effects combine and actually submit these slopes to climatal influences different from those which act on the opposite slopes, although they may both be situated under the same atmosphere.” Enumerating the geological formations of the High Alps, he shows that the most abundant are comparatively recent formations, many of them so friable that they crumble through exposure to the sun’s rays, without the super-added action of either frost or moisture; that limestones presenting all the appearance of great hardness, and selected on this account for enrochements, were found to be reduced to earth in two years; that others were not only liable to be disintegrated, but, efflorescing with what seem crystals of alum, lose at once their coherence and their chemical constitu- tion. And the torrents are found to abound in the mountain chains of unstable mineral composition ; they are more rare and less formidable in mountains of more compact constituents ; and in mountains of primitive rock they are altogether absent. Nowhere are torrents more furious or mere numerous than in the valley ‘of Embrun, extending over the whole land from Gap and Tallard to the village of St Crepin. Throughout the whole of this basin the base of the ‘mountain is of a slaty limestone, manifesting in a high degree the character given above. It is in this formation that innumerable ravines TORRENTS OF THESHIGH ALPS. 37 cut into the dry and bluish-tinted hills, which give to the mountains of Embrun their peculiar aspect. These hills are crumbled to such an extent that in trying to climb them one sinks often to the knees in the detritus. And this valley is situated in what may be called the point of intersection of the atmospheric and geological causes of the formation of torrents. To the north we travel over similar formations, but under a different atmo- sphere ; to the south we travel under a similar atmosphere but come upon soil of a different character,—and in both directions the number of the torrents is diminished, as are also their effects. Other illustrations of the same fact are given. Studying thus the natural history of torrents, he attributes their appear- ance to the simultaneous operation of several causes in combination. There appears to be (1) a geological cause—the nature of the soil; (2) a topo- graphical cause—the superficial aspect assumed by the country ; 3 and (3) a meteorological cause—the rainfall in the locality. And the question next raised is—Is the second of these seen in the existence and form of the bassin de réception, or basin drained by the torrent, to be considered a primary, or only a secondary cause of the torrent ? Surell maintains it is a secondary cause—itself a consequence, effect, or product of that to which it ministers. Were it otherwise, he says, in order to this being the case, it would be necessary that the cause which created these mountains should have moulded and shaped at one stroke these basins, according to the characteristic figure which they present to-day ; it would be necessary that this form, shape, and outline should have preceded all the action of the waters collected from them ; that these, from the first, should have found all the ground so moulded and prepared for them; and that they should have produced, from the first day, all the phenomena which they continue till to-day to present before us. But it is impossible, says he, to admit such a supposition. The bassins de réception are evidently the result of the violent and long-continued action of the water collected at first in a simple recess of the ground, and flowing over a soil deprived of coherence and consistency. What proves this decidedly is the presence of the larger lits de déjection, which have been formed entirely and exclusively at the expense of the lower-lying lands, whence the torrents issue. Every day, moreover, we see the bassins de réception increasing in magnitude. These effects follow on with such rapidity that a limited number of years should have sufficed to have produced enormous modifications in the original outline of the land. We have then only to carry back, so to speak, into olden times the action going on to-day under our eyes, supposing that present phenomena are the continuation of an action begun some centuries ago, and the digging out of the basin finds a ready explanation. And he refers to the facts already cited, that there are torrents of quite recent formation ; that new ones are being formed constantly ; and that these then aid in the formation of basins in the midst of grounds in which there was nothing of the kind previously existing. He goes on to say,—* I know well that I may seem to have exaggerated this action when there is considered the vast extent presented by the basins of certain torrents, and the profound depths of their declivities forming veritable valleys. But there should be taken into account, on the other hand, and at the same time, the enormous cubical contents of the deposits produced by them, which can have been obtained only from the erosion of v 38 RESUME OF SURELL’S STUDY OF such basins; and at the same time it should be recollected that the cubical measurement of these is still far from representing all the mass of material which the torrent has drawn away from the mountain, since a portion of this has been swept into the river, which has widely dispersed it far away. By an effort of thought let us transport the mountain formed by (this deposit to the upper part of the torrent ; let us throw this into the hollow constituting the basin ; let us add to this all that has been carried away by. the river, and we shall not be far from having filled up those deep excava- tions which we hesitated just now to attribute to the digging away of the waters, And we may come in this way to comprehend that there is no ex- aggeration in alleging that the whole valley of the torrent, from its birth to its junction with the thalweg, is the work of the waters alone.” Of the correctness of this view there are numerous corroborative indica- tions or proofs referred to ; and as the result of the whole of these observa- tions the natural history of many of the torrents in the High Alps appears to have been this: a deluge of rain such as is brought by the fwhn, falling on an exposed bare spot of greater or lesser extent on the col, or the summit, or the flank of a mountain, has washed away soil and formed thus a hollow basin with an outlet on its lower-edge, the water flowing off by this has made a little runnel carrying away, along with the earth washed out of the hollow, earth which impeded its progress; and as more and more fell into the runnel, through the undermining of its tiny banks, carrying this off also and depositing the detritus, whenever a reduced inclination of the ground reduced the velocity of the flow, and forming thus and there a tiny bed of deposit. But the operation—the process thus begun—goes on widening deepening, extending the basin drained, and the gorge or channel, and adding to the deposit, increasing both its depth and extent, till they have each of them attained the fearful aspect they now present. But there have been similar torrents in the same region in former times —which are now as innocuous as the extinct voleano—they too, to borrow the term, have become extinct; and the brushwood and trees growing on the bed of deposit tell by their age that these torrents have been extinct long. And while the its de déjection are now covered with vegetation, and in some cases with fields, and houses, and towns, the basin and the gorge have also been covered with forests. May not this have been the cause of the extinction? The more closely and the more extensively the subject is studied the more manifest does it appear that it must be so. Thus may it have been in the olden time. In more modern times the destruction of trees has preceded the formation of torrents; and the spread of the forests seems to have preceded the extinction of those of an older creation. This is in accordance with everything that is known in regard to the action of ‘trees in promoting the infiltration, retention, and percolation of water ‘through the soil, and subsoil, on which they grow. With the light thus obtained, we are enabled to trace back the natural history of the existing torrents to the destruction of herbage and trees formerly growing on the bare and exposed spots, from which these torrents have originated,—a destruction of which in some cases historical records direct us to the time in which it occurred; while in other cases it has occurred within the memory of the present inhabitants of the district, The student of physical phenomena may meet occasionally with what TORRENTS OF THE HIGH ALPS, 39 seems paradoxical facts, which do not appear to be in accordance with the law he thinks he has discovered. A modification of that law may, in some instances, be necessary to enable him to embrace by it all the facts of the case; but there may be other instances in which a more comprehensive view of the matter may show that the apparently paradoxical fact, so far from vitiating, establishes the law. Thus is it here. It is mentioned by M. Surell that there may be named a good many rivers which were navigable formerly, but are no longer so on account of the condition of their lower stream ; this may seem to be inconsistent with the general law which has just been propounded, but the study of the phenomena presented by some torrents supplies a solution of the paradox. To cite a case in point, the revers on the left bank of the Durance, from Savines to the river Ubage, is formed, it has been stated, by a succession of beds of dejection belonging to ancient torrents, which became extinct after atime. The whole district was covesed with forests, but these have been cleared away in a great measure, and the torrents resumed their ravages. Many rivers have attained to the state of stability, in the same way that many torrents have done so—by the spread of vegetation over the whole area of the grounds, through the midst of which their waters flow. If this vegetation were destroyed by any means, the soil being again left free, the stability would be interrupted, and devagation would be recommenced by the rivers, with effects similar to those connected with the devastations of the torrents. So that the undesirable change which has taken place in the per- manent flow of some rivers may be attributed to the denudation of their basin. This explanation, he says, has been frequently given, but without power to adduce direct proof of its correctness. But now the rekindling of extinct torrents by deforesting operations supplies the desiderated demonstration of an analogous fact. It may be considered, in some sorts, a special experi- ment on a small scale under exaggerated conditions, to render the effects more striking and more quickly produced. And thus may we obtain, from what has been termed the study of these torrents, information which may be turned to practical account in dealing with torrential floods in other lands, and in other circumstances, The peculiar characteristics of the torrents of the High Alps, consequent on the combination of atmospherical influences on the mineral composition of the mountains, seems at first to place them apart from all other analogous water-courses. But the study of these has revealed the homology which subsists and seems to run through the whole of these, making it appear that in the torrents of the High Alps we have only one excessive develop- ment of what is common to all,—which, having arrested the attention of Surell, has enabled him by this excessive development to study it without difficulty in all its details, and to show in them what may be seen ina degree less manifest, and it may be less developed, but not the less really existent, in all mountain streams, and to show that rivers also are only homologues of these. Comparing rivers with torrents, he finds and shows that the law of development of both is the same, marked by the same three stages, posses- sing the same characterestics, attained in the same way, the most stable in their course, having attained this stability after and by means of similar devagations, or changes of channel. And he goes on to say,—“ When we consider the wide-stretching valleys in which flow the Rhine, the Nile, we Mississippi, and the greater part of the large rivers which diversify the 40 RESUME OF SURELL’S STUDY OF surface of the globe ; when we observe that the bottom of these valleys is flat, levelled by the waters, and entirely formed by their alluvial deposits ; when, going back to the most ancient historic times, we see in Egypt, in China, in India, é&c., the first societies of men, descending little by little from the heights, occupied in struggling against the inconstancy.and the tremendous overflowings of these rivers,—may we not believs that all these courses have had, during a long course of centuries, changes in their channels such as those which the Durance exhibits now? But, gradually, the field of these devagations has been confined, as is seen so distinctly mn the case of torrents, and like these they have ended in being confined within their present banks. The Durance, on the contrary, is still existing in its second stage—that of instability—-which has succeeded to the first, charac- terized by a succession of lakes,.and to which in course of time a period of stability will gradually succeed.” And inferring that the most stable rivers of to-day have passed through an epoch of change, of course corresponding to the sevond period of torrents, he goes on to say,— In the study of these same rivers there have been collected a multitude of observations which show that they have had in a former age to open their thalweg, and to create their slopes the samme as we have said has been done by the Durance, and the same as we see being done under our eyes by the torrents in the interior of the continents ; they furrowed continents, they filled up basins, and the traces of these phenomena are still very apparent. In approaching these as they cast there immense deltas—ever enlarging deltas—on which sites for entire kingdoms have been found, which deltas constitute true beds of dejection. Thus have these rivers at a certain epoch of their existence acted as the torrents have done in the first period of their history.” : And he goes on to say,‘ Resuming this discussion, I will undertake to show in the action of torrents a faithful and miniature image of that which passed or will pass in all rivers in general. “In all I see three consecutive stages, succeeding each other in the same order, and dividing their existence into three distinct periods—First, a period of corrosion and elevation, which prepares the bottom of the thalweg and puts throughout its course the slopes in equilibrium with the resistance of the soil and the friction of the waters. It has for its end to determine the longitudinal profile of the water-course. “ Second, a period of devagation, when the rivers seek that form and those bendings of the course which correspond to the greatest stability (for the rectilineal course is uot the most stable, since it does not necessarily lead the current over those points where the bank is most solid and least likely to be changed). In this the action of the waters is confined to going hither and thither on the same level without perceptibly carrying away or eleva- ting the bottom ; it is the liquid mass which displaces itself rather than the soil. The result of this stage is to fix the laying out of the line of the course, or, if the expression be preferred, to determine the plan of it. “Third, in fine, a period of permanence, when the waters may overflow their banks but ever return again to their place in an unchanging bed. “The violence of torrents in the first period has been seen There ought to be the same in the first period of rivers; and this analogy ma. i : 4 ; y serve to explain the formation of those alluvial deposits spread out in such a m in the greater part of extensive valleys. If it be true that the miGuwtaine have been elevated successively in the midst of convulsions of which nothing TORRENTS OF THE HIGH ALPS. 41 can give us an idea, the waters have necessarily found in this chaos the matter of these enormous alluvial deposits. The rivers were acting at that time as our torrents do now—that is as these torrents do which have for their basins of reception entire chains of mountains, and which precipitate themselves across a soil newly disturbed and susceptible of being washed away, quite otherwise than that of our Alpine hills. Many hypotheses have been proposed to explain the origin of the Alpine pudding-like deposits. Along the Durance banks of these are met with which rise to upwards of 100 métres, or 330 feet, above the actual level of the waters. But the dejections of extinct torrents are, relatively to the trifling streamlets which now furrow them, deposits still more surprising, and of an appearance more inexplicable ; we are, nevertheless, well assured that they are the work of these streamlets in the first period of their action. Why then may it not be the same in regard to the puddings being the work of rivers in a period in every respect similar ? “T point out these things in passing, not daring to stop to develope and to follow out the views they suggest. This would take me too far away from my subject. Everyone can understand that a mass of water rolling over the soil must act in the same way and conform to the same laws, whether it form a torrent or constitute a great river. Now, as we see formed before our eyes the bed of torrents, we may infer that the bed ef rivers has been created in the same manner. And this presumption is accordingly confirmed by the study of such rivers as show traces of their action in bye- gone times in the soil of the valley they have formed.” In more than one of the British Colonies, and in other newly settled lands—using that phrase as applicable to the immigration and settlement of more highly-civilized nations than the native tribes—and in lands which have not been so colonized, are rivers in some of the earlier forms of development referred to. Now, dry channels, or channels threaded by a tiny stream, and now filled from bank to bank—a mighty rushing flood— carrying all before it, undermining banks and washing away the debris, the analogues of the torrents studied by M. Surell, having like them their bassin de réception—one of immense extent—covering it may be thousands of square miles, and embracing numerous secondary basins drained by affluents, a thunder-shower falling in any one of which may produce a torrential flood,—having their canal d’ écoulement, their water-course through which the waters roll their flood along towards the sea, and their lit de déjection, or bed of deposit, though this it may be is in the ocean-bed near to, or remote from, the shore, contributing in the former case to augment the bar which bars the river’s mouth. And it may be inferred that the application of like’ remedies may produce like effects. What bridles the torrent like a young lion in its fury may bridle the torrential river subject only occasionally to fits of rage. Section III.—Remedial Appliances to prevent the Destructive Consequences of Torrents. The natural history of torrents is suggestive of a most efficient remedy, but it is only of late years that it has been applied, and for its adoption we are indebted greatly to the study of these torrents by Surell, though he was 42 RESUME OF SURELL’S STUDY OF not the first to advocate its application, Until the natural history of these torrents was studied and made known special applications were in use, but a remedial cure seems not to have been attempted. What was tried was to prevent inundations, and the washing away of lands, and the deposit of detritus on fertile land. What is now being done is to extirpate the occasion of these. In the low-lying plains, at some distance from the mountains, it was the destructive effects of inundations which commanded attention ; in the Alps it was the ravages of torrents on the land which did this. “The torrent which dashes a great. body of water over very steep slopes (says Surell) undermines and eats away with fury the base of the banks, These fall in, and little by little pull down towards the bed the adjoining property, which is finally engulfed by the waters. As the banks are generally very deep their fall brings in its train effects the results of which extend far from the spot. All the surrounding land is disturbed. Some portions undermined subside, others slip, others break away, leaving deep crevices. Along the two banks of the torrent may be seen large chinks or rents running parallel to the bed. These subsidences, these rents, and this disturbance spread from place to place, repeat themselves to incredible distances, and end by including the whole sides of the mountain within the range of the effects. There are many quarters which can be named which the erosion of torrents have made so unstable that it has become impossible to build upon them. On the left bank of the torrent Les Moulettes there may be seen houses belonging to the village of Les Andrieux, which have been rent at a distance of more than 800 métres from the bed. On the highway, No. 91, opposite Les Ardoisiéres, we have an example of a consi- derable revers of a mountain eaten away by the Romanche and tormented by continual movements of the soil. The instability of the soil has com- pelled many families to abandon cottages situated at a great distance from the river. One could scarcely comprehend that that could be the cause of movements so remote, if the analogy of facts and other evidences had not proved it to be so in a manner the most irresistible.” Numerous cases are referred to in a note followed up with the remark,— “T have thought it right to multiply citations, because the cause of these movements has been often misapprehended, and notably so in the case last mentioned. The inhabitants attribute it to some particular character of the ground. Having under their eyes only the case of their own locality, they are not aware that it is a phenomenon quite general and common to all torrents.” He specifies movements of the soil in the mountain of Saint Sauveur, over against Embrun, brought about by the torrent of Vachéres, and by a great many other torrents of the third class, similar movements in the district of Vabries, mined by the torrent Crevoux on the left bank, and in the district of Villard Saint André, by the same torrent on its right bank ; it is stated that this ground had become more mobile subsequently to the formation of a canal for irrigation ; accounts are given of simiiar movements attributable to the torrent of Sainte-Marthe, near Caleyéres, in connection with which it is stated that there was there a mill apparently on the point of being engulfed, and of movements attributable to the torrent Merdanel, above Chadenas ; and it is stated that very violent movements have been observed in the portions of the Diveset, of Labéoux, of the Rabioux, of TORRENTS OF THE HIGH ALPS. 43 Boscodon, of the Ruisseauioux (Lauterat), dc. dc, And he goes on to say, —“There are whole villages built in bassins de réceptions which are threat- ened to be engulfed in this manner by the torrents, Every year the torrent acquires more of the ground, and the village abandons to it several cottages. These facts demonstrate the encroaching march of these water-courses. Little threatening at first, they increase in size, they extend themselves, and soon they reach the habitations built without mistrust at a great distance from their banks. There was, before the thirteenth century, on the borders of the Ralioux, near to Chateaureux, a monastery inhabited by the Benedictines. At a later period the monks deserted it through fear of its being engulfed, and now one sees the ruins suspended in the middle of the river's bank. “There are threatened with a similar fate the village of Lacluse, by the Labéoux (Dévoluy); that of the Hitres, by the Mauriand; that of the Arvieux, by the Moulettes ; the hamlet of the Marches, and the hamlet of the Maisonnasses, by the torrent Rousensasse, on the right bank of the Drac (Champsam).” Having specified these as villages or hamlets exposed to a fate similar to that of the Benedictine Monastery, whose history is given, he goes on to say, — Most frequently the undermining of the soil is done gradually, and this action is the more slow and the more regular in proportion to the extent ot the region. The great mass of ground deadens the movements, and impresses them with a kind of continuity. But at other times also the soil detaches itself suddenly, as if through the effects of a blow. It is thus that in the valleys of the Dévoluy, some years ago, a fragment of the mountain Auroux, covered with cultivated fields, precipitated itself, in one block, into the gorge of the torrent Labéoux. The commotion occasioned by this frightful fall was felt at a considerable distance in the village Lacluse, and the inhabitants attributed it to an earthquake. The cause was no other than erosion by the torrent, which had sapped the base of the ground. “This may demand some explanation. ; ‘Many lands are formed of parallel banks, disposed in flat layers and raised up on great inclinations. Often an interposed bed, more soluble or less tenacious, is decomposed or disintegrated by infiltration. Ifit happens at the same time that the under banks be attacked by the current at the foot, an enormous weight of ground finds itself suspended over an abyss ; the force of adhesion being weakened, it no longer suffices to keep together this mass and to attach it to the body of the mountain ; it is then detached in a mass, and it slides over the surface of the decomposed bed as on an inclined plain. One may indeed see similar land-slips frequently occurring in the limestones of the lias formation, which decompose with the greatest facility, and which often present a schistose stratification ; this kind of ground extensively prevails here. In other cases the grounds have been formed of the debris of the upper parts of the mountains; they compose a rough mass without stratification, and most frequently without consistency, covering the stratified nucleus of the mountain, and forming on its surface beds of great thickness, It rarely happens that a bassin de réception does not contain within its circuit a large strip of this quite recent formation, for it is into the scooped out parts that the debris have had to roll and rest, And one may easily see that the erosions which take place in such grounds, when they attack the foundation of very high banks, must force the soil to detach itself in great masses; and the fractures will take the form of 44 RESUME OF SURELL’S STUDY OF immense prisms, in accordance with laws similar to those regulating land- shoots (pousée des terres). So that it is in the abundance of certain kinds of grounds, and in the composition of the soil itself, that we find the secret of the principal power of these torrents. “And this is the evil to be met.” With these destructive effects of the torrents are conjoined the devastat- ing effects of the deposit of debris covering up fertile soil with barren sand, and gravel, and stones,—and, in some places, overwhelming not only cultivated ground, but houses and property not less necessary for the maintenance of the life of man, his wealth, and his comfort. M. Surell brings under consideration the several defensive appliances which had been employed in the bed of the torrent to prevent those destructive effects, and describes the respective merits of these. The first of these brought under consideration is a wall built along the base of banks in danger of being undermined; and the impotency and inefficiency of such a defence is exposed. The second consists of stone erections or wears raised across the bed of the torrent, to create an artificial fall diagonal to the torrent’s course, diverting it away from the ground _ which it is desired to protect ; such erections, it is stated, operate beneficially, and do so in two different ways,—they retain the bed of the torrent, and they diminish the velocity of the torrent for some distance above them. The first action prevents the sweeping away of the ground, the second deadens the violence of the current, thus not only preventing erosion, but destroying the cause of erosion. And details of their structure, of the extent of some, and of beneficial results which have followed the erection of them, are given. References are also made to fascinages, structures of fascines, or bundles of bushes, and to pallissades clayonnées, or stockades of wicker work, which are successfully employed elsewhere—but not there, In another chapter are discussed the defences employed in the valleys. Amongst the mountains, as has been intimated, the evil against which protection is sought is the erosion, and subsidence, and destruction of the ground ; in the valleys the evils to be guarded against are those resulting from the deposit of the debris of the mountain in places where it does harm. Of the magnitude of these evils illustrations are given; and the defences employed are classified under two heads,—epis, blocks or piles, and longitu- dinal dams. The effects of a single epi, and of a line of these placed diagonally across a portion of the stream, are described, as are also the structure and effect of dams, and the structure and effect of a third defence consisting of a combination of the two. A chapter is then devoted to the more full discussion of endiguements, the designation given to embank- ments designed for the defence of one bank of a river, the designation encasssement, or enclosing banks, being applied to structures designed for the simultaneous defence or protection of both banks. In regard to these effects, it is stated that, whenever in the bed of a water-course a resisting obstacle to the flow of the water presents itself— be it the projection of a rock, be it the bluff side of a mound or hillock, or be it an artificial obstruction—two effects manifest themselves. (1) The current is directed towards the obstacle and maintains this flow; t3} The current is thence reflected and directed against the opposite bank. The hurtful consequence of this reaction is constant, and it is so serious that it TORRENTS OF THE HIGH ALPS, 45 has called for special legislation ; and to this legislation on the subject a chapter is devoted. The legislation referred to is embodied in the Déecret du 4 Thermidor an XIII. relatif aux torrents du department des Hautes Alpes, Itis given in full in an appendix to the work, with much additional information in regard to the subject; and in the text is given a succinct account of the working of the law, with illustrations in justification of the same. From this it appears that when a new bank of a certain extent is ravaged by a torrent, the proprietors meet together and constitute a syndicat, or court, a requisition is addressed to the prefect, he commissions a civil engineer, officially connected with the department, intrusted with. the construction and conservation of roads and bridges—ingenieur des ponts' et chaussées,—to examine the ground, and, if it be necessary, to report the. works proper for the defence of the bank. F The work is executed in accordance with the adjudication ; the engineer superintends the construction, and sanctions the delivery of it; and the expense is borne by those interested, shared according to a scheme of division prepared by the syndic. A translation of the decreet will be given in the sequel. Attention is next given to the different modes of constructing the defences—(1) Levée en Perré; (2) Walls built with lime; (3) Drystone walls ; (4) Chevalets ; (5) Coffres. The first is employed by preference in longitudinal embankments; the three last mentioned are rarely employed but in the construction of épis ; lime-built walls are employed in both forms of defence ; the chevalet is a wooden erection of three pieces of timber stuck into the ground, apart below, meeting above, and sustained by a fourth piece stuck into the ground behind them, meeting them at the apex of the angle formed by them ; coffres are quadrangular structures of timber, the interior of which is filled with stones; the levée en perré is an embankment of earth faced with stone. A chapter is devoted to the consideration of a form of embankment called Dique éperonné or spurred embankments, Another is devoted to the consideration of the encaissement or confining of torrents, the outline to be given in the encaissement in section, the direc- tion to be given to the axis of the course, and the declination to be given to it. This is followed by a chapter devoted to the consideration of different systems of defence which have been proposed ; and three ehapters which follow are occupied with the condition of roads swept by these torrents, details of what measures are requisite to remedy existing evils, and of measures to be adopted in erecting bridges over the torrents. These constitute the third part or division of the work. The ground being thus cleared, M. Surell proceeds, with a view to the adoption of less objectionable and more appropriate remedial applications, to bring under consideration the causes of the formation and of the violence of the torrents, and with this the fourth part of the work is occupied. In discussing the foreign influences which have modified the primitive condition of the Alps, and produced definite effects on the formation or extinction of torrents, he gives prominence to the influence of forests. In successive chapters he discusses the influence of forests on the formation of torrents, and the influence of forests on the extinction of torrents, the decay 46 RESUMA OF SURELL’S STUDY OF of forests, and the influences of forest clearings and pasturage,—following the whole with a chapter devoted to illustrations and applications of the warning to be derived from the case of Dévoluy, which I have previously cited, The whole tone and spirit of these chapters produces an impression that the exposition of the view given is not only the result of a prosecution of the study of the subject, but probably an exposition of what first gave to him a clue to the discovery of all he subsequently discovered in regard to the natural history of torrents, and the appropriate measures for extinguishing them and preventing their ravages. I have often pictured him to myself as one day plodding along, gradually ascending a mountain valley, in the discharge of his professional duties, hig thoughts being at other times full of the subject of torrents and their numerous phenomena, but on this occasion thinking on anything but these. When, standing for a moment to rest and wipe away the sweat from his brow, looking back he sees what he cannot but perceive is an old torrent deposit—a veritable (it de déjection—though overgrown now with shrubs and herbs, with here and there cottages, and cottage gardens, and cotter’s fields. There it is! He feels he cannot be mistaken, Who would have thought to see it there and see it thus? But there is the cone-like forma- tion, the fan-like expansion spreading from the outlet of the gorge! Here is food for thought, and he goes on his way rejoicing. He comes upon a lesser Lit de déjection of recent formation ; how like and yet how different ! Here all is desolation; there all was clothed in living green, and the opening beyond showed a young and vigorous growth of trees. But stop! May not this have had something to do with the extinction of the torrent, and that more as cause than as effect? This is something to be thought about—I leave to others to follow out the train of thoughts thus begun. I find no difficulty in doing so till I picture to myself Surell master of the whole subject in all its details, and it is with these, his matured views, irrespective of the way in which they have been attained, that we have here to do. Writing on the influence of forests, or of the absence of forests, on the formation of torrents, he says,—‘‘ When we examine the lands in the midst of which are scattered the torrents of recent origin, we see them to be in every case stripped of trees and of all kinds of arborescent vegetation. On the other hand, when we look at mountain slopes which have been recently stripped of woods, we see them to have been gnawed away by innumerable torrents of the third class, which evidently can only have been formed in later years. “See then a very remarkable double fact: everywhere where there are recent torrents there there are no more forests ; and wherever the soil has been stripped of wood recent torrents have been formed ; so that the same eyes which have seen the forests felled on the slope of a mountain have there seen incontinently a multitude of torrents.” The names of numerous mountains and torrents, illustrative of both allegations, are given. “The whole population of this country may be summoned to bear testi- mony to these remarks, There is not a commune where one may not hear from old men, that on such a hill-side, now naked and devoured by the waters, they have seen formerly fine forests standing, without a single torrent. “ Observations which are reproduced so often, and with characteristics so constant, can we explain as simply the result of chance? Do they not force TORRENTS OF THE HIGH ALPS. 47 us to admit that forests exercise a powerful influence on the production of torrents, whether it be by standing on the soil they defend it against their approach, or, obliterated by the hand of man they leave to them an open field which they are not slow to devastate ? ‘ “Tt is of importance to establish the fact of this influence by direct and positive proofs. Here we are almost embarassed by the very amount of evidence. It should be known that this influence manifests itself here in so many varied circumstances, in such a variety of forms, and with such a force of truth, that assuredly not one man throughout the whole country would dare to dispute it. It is only necessary to spend one day traversing these mountains to be struck with an infinity of facts fitted to produce conviction in opposition to theemost rooted prejudice to the contrary. All of those who know the country can have, on this point, but one opinion. All the observations on this matter which have been published are of one accord, and the authors have had no other trouble than to verify the public opinion, nor other merit than to express by the pen that which has been for many ages in all mouths and in all minds.” In face of a belief so universal, so little disputed, and so indisputable, one finds himself at a loss when he tries to reduce it to a kind of demon- stration ; he knows not how to select one from so great a number of cases, which corroborate one another, and the force or power of which lies in their cumulation ; and he thus writes on the influence of forests on the extinction of torrents :—‘‘In examining the basins drained by great extinct torrents, there are almost always found there forests, and often dense forests. There may be observed also, along wooded rever's, a number of small torrents of the third class, which appear as if stifled under the mass of vegetation, and are completely extinct. Now this second observation, which can be verified by a multitude of examples, supplies a demonstration of a fact of which the first only permitted us to entertain a suspicion in a vague way :—it is, that the forests are capable of briuging about the extinction of a torrent already formed. Indeed, it is impossible to admit that the small torrents, dug for the most part in mobile and friable ground, can have died of themselves, so to speak, in their very birth, and through the effect alone of that equili- brium to which reference has already been made. “ Stability cannot establish itself so speedily on beds which are scarcely formed, and in the midst of lands which offer still so much food for erosion by the waters ; it is a work which demands time, and which is never entirely consummated until the mountain has been gnawed away to the quick, and to its last ridge. “ Amongst the great number of extinct torrents, the basins of which are wooded, there are some the forests of which have been subjected to the commune régime, and have fallen in part under the axe of the inhabitants, Very well, the result of this destruction of trees has been to rekindle the viclence of the torrents, which only slumbered. There have been seen thus peaceful streams give place to furious torrents, which the fall of the wood had re-awakened from their long sleep, and which vomited forth new masses of déjection on beds of deposit, which had been cultivated without suspicion from time immemorial. This is what has been remarked more especially after the excessive destruction of woods which followed the first years of the Revolution ; the devastations of many great torrents only date from this epoch. It is from this time that the torrent of Merdanel has advanced towards the village of Saint Crépin, the inhabitants of which are to-day 48 RESUME OF SURELL’S STUDY OF within a little of being ruined. The same observation has also been made on the Lower Alps. We may cite as an example of what has been said the whole of the revers which are situated on the left bank of the Durance, from Sabines to the river Ubaye. It is formed exclusively by a succession of beds of dejection belonging to ancient torrents, which had been extinguished after having gnawed away a great portion of the mountain of Morgon. The whole of this district was covered with forests, which have been cut up with clearings, and which continue to be impoverished still further every day. The torrents also have commenced their devastations, and, if the destruction of woods be continued with the same recklessness, this revers, fertile to-day, will speedily be ruined, as so many others have been. _“ This last fact completes all that need be said in regard to the influence of forests. In seeing these show themselves almost everywhere on the body of extinct torrents, one may suppose that these had first died, and that the woods had then seized upon them when the extinction had been completed, and when the soil of the neighbourhood, become stable, permitted vegetation to develope itself in safety : the forest would then only have been one of the effects of the extinction of these, instead of being the cause of it. But then the destruction of the woods would only have restored things to their pri- mitive state, and the torrent ought to have been able to continue extinct after the taking away of the woods as it was before their appearance there —and this is exactly what does not happen. It has sufficed to clear away the woods to see the devastations immediately reappear. It must be then the forests which, by their permanent appearance on the soil, hindered the devastations, and it is the forests, in taking possession of the soil, which have again caused them to cease—and the extinction of the torrents is so completely their work that it begins, continues, and disappears with them, the effect ceasing immediately with the cause. ; “One sees by this that the action of forests is not confined to preventing the creation of new torrents, but that it is sufficiently energetic to destroy torrents already formed. One sees also that the injurious result of the removal of woods is not only to open everywhere the soil to new torrents, but that it augments the violence of those which exist, and resuscitates those which appear completely extinct. We may then sum up the influence which forests exercise on torrents already formed in two facts, parallel to those which sum up tbeir influence on lands where the torrents have not yet appeared. (1.) The presence of a forest on a soil prevents the formation of a torrent there. (2.) The destruction of forests leaves them subject to become the prey of torrents. Nor is there in this any thing for which we may find it difficult to account. “ When the trees fix themselves in the soil the roots consolidate this, inter- lacing it with a thousand fibres ; their branches protect it, as would a buckler against the shock of the heavy rains ; and their trunks, and at the same time the suckers, brambles, and that multitude of shrubs of all kinds which grow at their base, oppose additional obstacles to the eurrents which would tend to wash it away. The effects of all this vegetation is thus to cover the soil, in its nature mobile, with an envelope more solid and less liable to be washed away. ~ Besides, it divides the currents and disperses them over the whole surface of the ground,)which keeps them from going off in a body in the lines of the thalweg and meeting there, which would be the case if they flowed freely over the smooth surface of a denuded ground. Finally, it TORRENTS OF THE HIGH ALPS. AQ absorbs a portion of the waters which are imbibed in the spongy humus, and so far it diminishes the sum of the washing away forces. (“It follows from this that a forest, in establishing itself on a mountain, actually modifies the surface of the ground,)which alone is in contact with atmospheric agents, and all the conditions find themselves then modified as they would be if a primitive formation had been substituted for a formation totally different. Whence it is not more astonishing to see the same soil alternately cut up or free from torrents, according as it is despoiled or clothed with forests, than it is astonishing to see torrents cease when we come to primitive formations, or reappear suddenly on friable limestone. “In accordance with this we find—first, the development of forests brings about the extinction of torrents; second, the destruction of forests redoubles the violence of torrents, and may even cause them to reappear. And nothing is more easy than to explain these new actions. It will be remembered what are the causes which call forth and maintain the violence of torrents: it is, on one hand, the friability of the soil ; and, on the other, .the sudden concentration of a great mass of water. Now, we know already that the forests render the soil less liable to be washed away ; we know also that they absorb and retain a portion of the rainfall, and prevent instan- taneous concentration of the portion whieh they do not absorb. Conse- quently they destroy both the one and the other cause. They prolong the duration of the flow, and they render the floods at once more prolonged, less sudden, and less destructive. “Tt may be understvod from this how forests, in invading the bassins de réception, may have contributed powerfully to stifle certain torrents. Whilst the waters were creating for themselves the most convenient slopes, the forests were retaining the soil which was ready to go, was rendering it more solid, was consequently diminishing the mass of earth washed away, and above all was opposing itself to the concentration of currents. They were augmenting all the resisting, all the existing, obstacles, and were diminish- ing all the motive powers ; and they were coming thus to hasten by a double efficacy that epoch of stability in which the force of the waters would find itself in equilibrium with the resistance of the soil. There is one circum- stance which ought to render their triumph still more speedy,—it is, that the torrent, in proportion as it is enfeebled, abandons to them a soil more and more stable and favourable to vegetation, in such a way that this augments every day their forces in proportion as the torrent loses force. In fact, if the expression may be allowed, it is reinforced by the effect. “ By this I do not mean to say that the torrents can never become extinct of themselves. That would be in contradiction to what I have said, and at the same time to facts observed, for there are examples of torrents being extinguished without the presence of forests, and solely through the erosion of the mountains—as, for,instance, the torrent of Saint Joseph, near Mones- tier. But I say that the forests expedite the accomplishment of this effect, and that they can produce it where the other circumstances are not yet producing it. “Thus nature, in summoning forests to the mountains, places the remedy side by side with the evil. She combats the active forces of the waters ; to the invasions of the torrents she opposes the aggressive conquests of vegeta- tion. On those mobile revers she spreads a solid layer which protects them against external attack, somewhat in the manner that a facing of stone protects an earthen embankment. It is worthy of remark, that the little D 50 RESUME OF SURELL’S STUDY OF cohesion of limestones, which is opposed to the fixing of grounds, which renders them so mobile, and draws torrents thither, is precisely the quality which renders them favourable to the development of vegetation. The game cause which multiplies the torrents ought then to multiply also the robust forests, and to cause productiveness to succeed in the long run to barrenness, and stability to disorder. Not that, strictly speaking, there can be in nature anything otherwise than orderly, for there is nothing which is not subject to the rule of immutable laws, but in popular phrase the term disorder has also its meaning. “One is struck with the illustrations of the observation which has just been made in going over certain forests in these mountains. One sees the vegetation doubling its profusion and energy in grounds torn by ravines, and crumbling on all hands, as if it were mustering its last efforts to retain a soil escaping from it. To cite one example: in the forest of Boscodon may be seen the vigour and tenacity of the vegetation contending against a friable soil composed of schist, tufa, and gypsum. It is, in fact, the lands which are the most mobile which are at the same time the most fertile, and the hard rocks on which vegetation has no hold, brave also the effort put forth by all the causes of destruction. The mountains, if they were abandoned quite naked to external influences, would soon be levelled or cut up into bits, and they would offer to man nothing but a heap of cleft rocks, unculti- vated and uninhabited. “Tt is vegetation which prevents this ruin; and as there can be no vegetation without water, it is on the mountains that nature has poured out the water in the greatest profusion, We have already called attention to the remark, that there falls more rain on the mountains than on the plains. The mountains attract and retain the clouds [%]. Snows and glaciers crown their summits as immense reservoirs, whence trickles out a perpetual moisture, and whence flow innumerable streamlets which fertilize their sides, and distribute fertility, from brow to brow, down to the very depth of the valleys. Thus, the waters which are the most energetic means of destroying the soil are at the same time the most active in its conservation. In drawing on vegetation, they preserve the soil against their own attacks, and the more they have of power to destroy, the more vegetation they cause to spring up to preserve. It is in this way that nature imposes on all her forces moderators which counterbalance them and keep them from acting always in the same way ; and this must end in bringing everything to a state of restored peace.” And dwelling on the thought of self-adjusting provision for the natural extinction of torrents, he thus, in something like a burst of enthusiasm, gives expression to his feelings in view of the thorough and efficient way in which torrents had naturally become extinct, and the contrast thus pre- sented to the puny endeavours of man to restrain their ravages : the natural and the artificial ; God’s way of doing it, and man’s way of doing ; the work of God and the work of man ; and the results : success, perfect and complete ; and success, partial and imperfect ! ; “Let us go back for a moment,” says he, “and compare these effects of vegetation with those exercised by the different systems of defence hitherto devised. The result of defences like that of vegetation is to arrest the ravages of torrents ; and how powerless appear all embankments by the side of those great and powerful means which nature employs when man TORRENTS OF THE HIGH ALPS. 51 ceases to oppose her, and when she patiently prosecutes her work through- out a long series of ages! All our paltry works are nothing but defences, as their name indicates ; they do not diminish the destructive action of the waters, they only keep it from spreading beyond a certain boundary. They are passive masses opposed to active forces ; obstacles, inert and decaying, opposed to living powers, which always attack, and which never decay. Herein is seen all the superiority of nature, and the nothingness of the artifices devised by man. “1 make not here a barren comparison. I wish to let it be seen that it is better to bridle the torrents than to erect at great expense masonries and earthworks, which will always be, whatever may be done, expensive palliatives, better adapted to conceal the plague than to eradicate it. Why then does not man ask assistance of those new powers, the energy and efficacy of which are so clearly revealed to him? Why does he not command them to do yet again, and that under the directions of his own genius, that which they have already done in times long gone by on so many extinct torrents, and that under the prompting of nature alone ?” With the views thus expressed he proceeds to discuss more thoroughly the measures to be adopted for opposing, counteracting, subduing, and taming tor- rents. He argues that the continued application of such measures of defence as have been referred to must necessarily fail ; and he alleges that prevention —not cure—must be attempted. This, says he, resolves itself into two distinct problems—(1) To prevent the formation of new torrents, and (2) To arrest the ravages of torrents already formed. But the remedy proposed by him, as applicable to both, is the same— namely, the extension of vegetation. “All the facts which have been adduced,” says he, “carry with them the conclusion to which they lead, and it would be superfluous to go back upon them. It is vegetation which is the best means of defence to oppose to torrents.” And starting with this idea, the two problems resolve themselves into the discussion of the pro- ceedings to be followed to throw the greatest possible mass of vegetation either on to the lands threatened with torrents in the future, or on to lands surrounding existing torrents. “Tn doing this, art,” says he, “should confine herself to imitating nature, to mastering its forces, and skilfully to opposing one of these to another, All that we are about to undertake nature has already done before us in time past, and she does it over again to this very day under our eyes when- ever we leave her free to work. We are assured, then, beforehand of success, since all we have to do, to a certain extent, is to recommence experiments already made, and the success of which has been complete. Whence also it follows it is no longer a system of defence we have to seek, but a system of extinction.” As a preliminary measure, he argues the reservation, by legislative enact- ment, of certain portions of the soil ; and a limitation or restriction of the number of the flocks and herds within what the reproductive vegetable power of the district can sustain. He recommends that the land to be defended against the ravages of the torrents should then be marked out by tracing, on each bank of the torrent, a continuous line, following all the windings of its course, from the highest point of its commencement to its issue from the gorge. “The strip of land comprised between each of these lines, and the summit of the mountains, would constititute (says he) what I 52 RESUME OF SURELL’S STUDY OF would call a zéne de defense, enclosed against flocks and herds, The zones of the two banks, following the outline of the basin, would meet in the hei ghts, and would begird the torrent like a girdle. The breadth, varying with the slope and with the consistency of the soil, would be about 40 métres, or 130 feet, below, but it would increase rapidly as the zone rose on the mountain ‘side, and it would end in embracing a space of 400 or 500 metres, or from a quarter to a third of a mile. «This outline would require to follow, not only the principal branch of the torrent, but also the different secondary torrents which degorge into the first ; following then the ravines which each of the secondary torrents receives, and going on thus, from branch to branch, it would go on to the birthplace of the last threadlet of water. In this way the torrent would find itself begirt thoughout the most minute of its ramifications, These zones of defence, in penetrating the bassin de réception, will be enlarged ; while, on the other hand, as the ramifications are in this part more multiplied and more approxi- mated, it will come to pass that neighbouring zones will join and even over- lap each other, and their outlines will be.lost in a common region, which will eover the whole of this part of the mountain, without leaving there a void space. The zones of enclosure being thus determined, the first part of the operation is finished. But this is in some respects only the outline of the periphery of the work which is to be done. “We have next to do with what may be the most active and prompt means of drawing veretation over the whole surface of this enclosure. For this purpose it should-be sown and planted with trees ; where it may be impossible to raise trees at once, the growth of shrubs, bushes, and thorns should be stimulated ; but on the height, where the zones include the whole extent of the bassin de réception, it is a forest which must be created. The best adapted kind of trees must be selected ; recourse must be had to all modes of procedure, indeed, even to modes of procedure which have yet to be discovered, and which go beyond experience. The work must be done any way and every way ; and the end aimed at in these works ought to be to cover the bassin de réception by a forest which will every day become more dense, and which, extending itself step by step, will end in spreading even into the most hidden depths of the mountain. 5 “ Tf the vegetation thus developed over the zones of defence be protected against flocks, if it be protected against the depredations of the inhabitants, if it be tended, maintained, stimulated by all means possible, it will ulti- mately envelope all the parts of the torrent by a very dense thicket, and thereby will be realized two effects at once, both of them equally salutary. “First, this will arrest the waters which trickle down the surface of the soil, and will keep them from entering the torrent ; or, if it do not prevent them doing this, it will at least retard them, and we know that this result ig in every way a happy one. From the time this is done the torrent will only receive the waters which fall vertically from the sky into its bed ; and this will diminish its volume in the same proportion as the proportion which exists between the extent of the general basin of the mountains and that of the stringently reduced opening presented by this bed. From a considera- tion of the great difference in extent of these two surfaces may be under- stood how great should be the reduction of the body of waters thus effected. And next, the ground of these zones can be no more washed away by the rains, and swept away by the torrent, and thereby will be diminished so far the mass of deposited matter, It is true, it may indeed be swallowed up little TORRENTS OF THE HIGH ALPS. 53 by little if the foot of the banks be undermined by the waters, but this constitutes another point to be attended to, and one to which I shall attend immediately, and on which, until I do so, I crave for a moment a suspension of judgment. “To return, I give in one word the effect of these arrangements. I may say that the torrent will find itself placed in the same conditions as if it issued from the bosom of a deep forest, which wiJ] surround it in all its windings, and in which it will be as if it were drowned. Elsewhere I have described the results to which such a condition of things gives birth. It may be remembered as the forest struggling with the water ends in extin- guishing the torrent, the same effects will reproduce themselves here, and it is unnecessary to repeat them. “ By the same analogy it may be understood that the vegetation advancing always, and gaining each day upon the ground, should descend on the banks and carpet them almost to the bottom of the bed, as has happened in exten- sive torrents; but the giving of permanence to the banks is a result of too great importance to be left thus to the caprices of the soil, and of the free will ofnature. We come thus to a third department of the work. It is one in which it is especially necessary to redouble care and to multiply devices. “To draw the vegetation over the banks they should be cut with small canals of irrigation derived from the torrent. These will impregnate with fertilizing humidity the land now rent and dry; they will break also the slope of the declivities, and serve to render them more stable, and soon they will disappear under the tufts of various plants brought to light by the water. “The formation of these canals being extended ultimately to the summit of the bank, the water will thence penetrate the zones of enclosure and fertilize their soil, It is in the retention of the water, and in the possibility of opening everywhere and multiplying almost indefinitely provision for this, that rests in reality the whole future of the work. “Tn fine, I pass to the fourth phase of the work, which is also the last. Whilst all these plantations retain the grounds through which the torrent flows, the undermining may be prevented by the construction of artificial barrages, or wears. ““We thus borrow from existing systems of defence that which is most efficacious in them ; but in doing this how greatly have we ameliorated the circumstances in which we set to work ! “Indeed, we shall find in the plantations, everywhere where it is thought fit to establish these works, the best material for their construction. The young trees will supply stakes, prunings and bushes will supply facines. We can then construct the barricades of facines, or the wicker palisades recommended by Fabre. These works will cost little for manufacture, the materials will cost absolutely nothing. They will be cheap ; and they do not present the dangers whichaccompany walls of masonry. Onecanthen multiply them everywhere without any inconvenience, and almost without expense. “ These barricades will be like the completement of the works of extinction ; they will serve to defend certain banks till the vegetation has reclothed them over all their extent, and till the torrent itself shall have lost the greater part of its violence. They can be employed also to stop up the secondary ravines, to intercept the little ramifications, to fill up small holes ; in fine, to lead over the surface of the soil, and thus completely efface those innumerable streamlets divided like the hair-like fibres of a root, which are really and indeed the root of the evil. 54 RESUME OF SURELL’S STUDY OF “ Behold the work completed ! “In recapitulating what has been said it will be seen that it resolves itself into four parts—first, the tracing of zones of enclosure ; second, the covering of these with trees ; third, the extension of vegetation over the banks ; and fourth, the construction of barricades of facines, of brushwood, or of wicker-work. “One thing remains yet to be adverted to. I must speak for a moment of the order in which the work should be advanced. This order, far from being arbitrary, is an element of first importance, and a most essential element of success. I have already so often, in the course of this work, brought forward the necessity of attacking the torrents at their source that I believe it to be unnecessary to dwell uponit now. Thus, then, it is in the highest parts that the works should be first undertaken, thence to be extended to the parts of a lower level. Not only should a commencement be made by planting the bassin de réception before giving attention to the lower zones, but even in this basin the commencement should be made in its highest ramifications. One should go above the last traces of the bed, up to the abrupt slopes furrowed with ravines which the waters form and deform with each storm of rain,—it is there that the first works should be established ; one should afterwards—but only afterwards—carry them lower, but making sure first that the parts left are quite consolidated.” A chapter is devoted to the discussion of the practicability of carrying out such measures ; and another to the consideration of the legal difficulties in the way of this being done. In a résumé of the work proposed, he concludes his recapitulation, saying, —“The definite result of the whole will be the creation of forests; the whole work may be summed up in one sentence :—Reclothe with woods the more elevated parts of the mountains. If it be true, that forests exercise an influence on the climate, the effect of this extended mass of new woods will be to render the showers of rain less heavy, the rain-storms more rare, and the whole atmosphere more moist and more showery ; the climate will then, by insensible degrees, be changed at the same time as the surface of the soil ; and thus the two causes of torrents will be destroyed at one and the same time, and a general result will have been obtained while seeking at first only to remedy a particular evil.” But, he goes on to say, the work of reclothing the heights with wood will not of itself render unnecessary the construction of dams and wears; and he proceeds to indicate the application of embankments, which would meet the requirements of the case with which he had to do—the prevention of ravages by torrents. The question of expense is then discussed ; reasons are adduced to show that the expenses should be borne by the State. And, in a recapitulation and conclusion, the various measures proposed are reviewed and defended against such objections as it was thought possible might be brought against them, Such is an analysis of the Study of the torrents of the High Alps, to which may be traced the commencement of the works of reboisement and gazonnement which are now being carried on, on a gigantic scale, in the Alps, the Cevennes, and the Pyrenees. But it is by no means the only work advocating such measures ; and I proceed to supply information in regard to other works, treating of the same subject, published before and after this work of Surell’s, PAE ALT. LITERATURE RELATIVE TO ALPINE TORRENTS, AND REMEDIAL MEASURES PROPOSED FOR ADOPTION TO PREVENT THE DISASTROUS CONSEQUENCES FOLLOWING FROM THEM. Tue subject treated so exhaustively by Surell has commanded the attention of many besides him. In 1797 was published an Essai sur la theorie des torrents et des rivieres, by M. Fabre, an engineer referred to by M. Surell, who had made these his study. The following are translations of some of his propositions relative to them, and to appropriate remedies for them. “144. The destruction of the woods which cover our mountains is the primary cause of the formation of torrents. “The reason is apparent. These woods, be they timber forests or be they high coppice, intercept by their foliage and by their branches a considerable portion of the water falling in- rains and in thunderstorms. The remaining portion, which they could not retain, falls only drop by drop at intervals sufficiently long to let them have time to filtrate into the earth. On the other hand, the bed of vegetable earth, which goes, on increasing annually, imbibes a considerable quantity of these waters. In fine, tufts of herbage and bush break and destroy at their origin the torrents which might have been formed notwithstanding all these obstructions. The woods being destroyed, the waters of a storm no longer meet with any- thing in their fall to intercept them. They cannot, by reason of their abundance, be absorbed by the ground as they fall. They flow over the surface, and meeting no more tufts which might have broken and divided their courses, they form torrents, as has been said. “145. The clearings on the mountains are the second cause of the formation of torrents. “We have shown that a torrent will be formed with so much the more facility in proportion as the matters which compose the mountain shall have less tenacity. Now the clearings, in rendering the earth friable and mobile, have diminished this tenacity; and thus they have favoured the formation of torrents. “One may see from this how ill-advised and inconsiderate was the law given under the ancient régime, which authorised clearings, provided there ' were constructed at intervals walls of support to keep the earth on the slopes of mountains. It was not seen that in a great many countries the people confined themselves to raising two or three crops on a clearing, and that they then abandoned it. It was natural, this being the usage, that the sustaining walls, coming to cost more than the crops would repay, would not be constructed ; and this is just what has happened. But there has already resulted from this, and there will result from it in the future, frightful disasters, as we shall now see. 56 LITERATURE ON TORRENTS. “146. The first disaster produced by the two causes of which we have just spoken is the ruin of our forests. “ Tf there had existed wise laws, and these had been carefully executed, we should have had now building timber in such quantity as to permit of exportation, We should also have had in abundance wood for carpentry and fire-wood. It is felt that both of these things are essentially necessary in a well organized state. But they fail us to such a degree that in a great number of communes there is not even fire-wood. The evil has been long felt, and the necessity of remedying this is urgent. “147, The second disaster is the destruction in a great many places of the bed of vegetable soil with which our mountains were covered. “This bed would otherwise have produced abundant pasturage for the sheep, but, carried away by the storms and torrents, there remains at present on these mountains only a naked and dry rock. From this results necessarily a diminution of the small number of cattle which France might have been able to support if these pasturages had continued to exist. “148. The third disaster is the ruin of the domains which le upon the rivers. “ We have seen that the swellings of the torrents were stronger in proportion as the mountains were less wooded and more impoverished. These swellings are then greater now, through the operation of the two causes mentioned above, than otherwise they would have been. They ought, therefore, to cause, and they do really cause, much more havoe to the domains along their course than they otherwise would have caused. “On the other hand, we have seen that it might happen, as it has in effect happened too often, that the torrents in issuing from their bed or channel would cover adjacent domains situated at the foot of the mountains with deposits, which absolutely alters their nature. Now, this never happened until that by the operation of the two causes mentioned above the torrents were formed. “149. The fourth disaster is the drainage, experienced in the navigation of the rivers, by the divisions in the water-courses, which are the consequents of great floods, “150. The fifth disaster consists in the strifes and contentions, between the proprietors on opposite banks of the river, to which the divisions in these water- courses give ise, “151, The sixth disaster results from the deposits which they make at the mouths of the streams, which often intercept the navigation.” Each of these three statements is illustrated in detail. “152. In fine, the seventh disaster consists in the diminution of the sources which feed the streams and the rivers in their ordinary state. “We have seen that springs, the sources of streams, are formed from the rains which filtrate through the earth and meet in the subterranean reser- voirs, whence they escape by minute channels, and make their appearance at the surface of the ground. Novw, if the mountains be despoiled of their bed of vegetable earth, and there remain only the bare rock, it is evident that the water of the rains will no longer filtrate through the soil, but will flow quite superficially ; thence it follows, that as the fountains diminish so must the rivers which they feed; and a time will come when even the rivers which at present are navigable will cease to be so. True, indeed, that time is still distant, but sooner or later it will arrive if the cause whioh produces this effect be not destroyed.” FABRE’S ESSAI. 57 With these views M. Fabre urged then the planting of trees, or the reboise- ment of the mountains, and the protection of these throughout their growth. He thus states his opinion :—“ We have said that the destruction of the woods which were covering the mountains, was the primary cause of the formation of the torrents. To destroy the effect, the cause must be exterminated. Therefore, if there be still vegetable earth on the mountains, it will be well to leave these to become clothed again with wood, by leaving them in fallow, and with a view to the same end, it may be well to remove every- thing which might damage the young trees. For this reason, most rigidly should be carried into execution the laws relating to the. prohibition of goats, for it is known that the tooth of this animal is murderous to young trees. It is not less essential to provide for the conservation of existing woods, since these woods, which have kept the torrents hitherto from being formed, are to us a sure guarantee that they will prevent the formation of them in the future. “Clearings are the second cause of the formation of torrents. It is necessary, then, that after having been too extensively tolerated by the ancient laws, these should be restricted within prescribed limits. In con- sequence, we consider, that in this respect, they should be conformed to the following rules :—First, a clearing ought never, under any pretext whatever, to be permitted on the slope of a mountain, which has less than three of a base for one of vertical height, z.e. a slope of one in three. “ Second, the clearance might be permitted on one of less declivity, but only under the restrictions we are about to state. “ Third, the clearance ought never to be authorised, but on the verge, or in transverse horizontal strips, or on a level, or what is nearly such. “ Fourth, in this case the strips of fallow should be separated from one another by other strips, likewise horizontal or level, left uncultivated, on which the wood should be -permitted to grow. “ Fifth, these uncultivated strips should be made to take the place of the sustaining walls, prescribed by the law previously spoken of. It appears that they should not be less than five tovses, or thirty feet, in breadth, to enable them, in case of need, to destroy a torrent which might be formed on the strip of fallow above it. “ Sixth, the breadth of the strips of fallow should be only five ovses, or thirty feet, where the slope.of the mountains may be one in three; but it appears that it may be increased with the diminution of the slope, ‘until a slope is arrived at, which leaves no cause of fear of the formation of torrents, in which case the breadth may be unlimited. “Seventh and lastly, the clearings should in no case be permitted without the authorization of the respective municipal authorities, and after the specification and plan, which shall have been previously made by a public official of what is proposed in each commune. “ Every one must see that by some such regulation we may escape for the future all the disasters produced by arbitrary clearings, almost always ill- arranged, both as they affect the interests of the community and those of the individual. Nature is only the more active when aided by human industry, and so in cases in which it is wished to hasten on, on certain moun- tain slopes, the increase of woods, it would often not be bad to sow acorns and beech-nuts, or seed of any species of trees which may be presumed to be proper to the localities. There is more than one country where they are-quite accustomed to do so, E 58 LITERATURE ON TORRENTS. “There are cases where there remains so little earth on the mountains as to lead one to conclude that wood will there make but little increase ; such grounds may be laid with turf, and sown with seeds of plants which may be deemed most proper for the localities. The superficial tissue formed of turf will be an obstacle to the formation of torrents, and by this means besides will be created useful pasturage. “These are the means of preventing the formation of torrents on the mountains. It remains for us to see those which must be employed to destroy, when the thing is possible, the torrents already formed.” The views advanced by M. Fabre have never, so, far as I know, been subverted ; and by subsequent studies of the phenomena many of them have been confirmed. But it has been objected that the subject was not one which admitted of being discussed in such precise propositions as those in which he invested his views—that some of his propositions were based on deduction rather than founded on an induction of fact—and that, in the absence of facts, adduced to establish or support his deductions, there was an element of uncertainty thus introduced into his conclusions, which prevented them being made the ground of extensive practical undertakings, involving great expenditure, until they had subsequently been verified by renewed observations of facts systematically conducted. This circumstance makes the work more valuable to any one desirous of studying the subject in all its aspects. It is a work to which Surell often appeals, as a work the value of which was indisputable, and as the only work going to the root of the matter in discussing a subject not exactly the same but one nearly allied to that to which he was giving attention. And he mentions that Fabre had himself announced, that no work on the subject had previously been published, praying that the imperfections of his work might be borne with in view of the novelty of the matter. Surell speaks of Fabre as an engineer who had occupied himself with this study, and he says of the work by him, that it contains a complete des- cription of torrents, with just, and often ingenious, remarks on their action ; but he states that he considered the form of aphorism in which his obser- vations are couched a defect, exposing them to the objections I have cited. He states further that it is clear, from many passages, that the torrents seen by M. Fabre were not those of the High Alps, which were those which were the subjects of his own study, though they were similar to them in many respects ; and that his theory, when applied to them, was not always borne out by the phenomena presented by them, or did not cover these: that it was evidently based on the observation of torrents, which devastated the South of Provence, and more especially the torrents of the Var, where he was Ingénieur en chéf. But all of these considerations make his observations and conclusions the more valuable to any, who may be studying the subject, with a view to the discovery of remedial measures, appropriate to countries very differently situated from the ravaged and devastated regions of France. We find in Fabre and Surell, men of ditferent casts of mind, belonging to different generations, following their professional pursuits in districts far apart and differently situated, propounding doctrine essentially and substantially the same. With regard to the deficiency of observations as a foundation of M. Fabre’s counsels, such observations were greatly desiderated by him; he stated that no work on the subject had been published, and he craved that LEOREULK AND H&RICART DE THURY. 59 the defects of his work should be excused in view of the novelty of the subject of which it treated. In 1804 there were published Reserches sur la formation et Vexistence des ruisseaux, des rivieres, et torrents, by M. Lecreulx. The design of this publi- cation was to refute the views advanced by Fabre ; but it has been alleged that apparently the author did not know the kind of water-courses to which Fabre in his work had a reference. On this point M. Surell writes—‘“I searcely know whether Lecreulx meant positively to dispute the position that woods have an influence on the production of torrents. In attacking Fabre on this point all that he does is to bring to light his complete ignorance of the kind of mountains and of the kind of water-courses which Fabre had specially before him. Lecreulx had always before his mind the case of the Vosges, which comes up in every page of his book. I know the Vosges well, and I can affirm that these mountains no more resemble the High Alps than the German patois, spread over several of the valleys, resembles the provingal dialect which is here the general language of the country.” In 1806 appeared a Ptomographie des cours @eau du Département des Hautes Alpes, by M. Héricart de Thury, in which are pencilled rapid sketches of the geological characters of the beds of the water-courses of the Department, and his work supplies data valued by students of the country, seeking to discover the cause or occasion of the ravages which these water- courses make, and a remedy for the evil. He reckons eight distinct basins or river valleys in the High Alps. Surell reckons three, but this affects not the facts recorded: it resolves itself into a mere question of judgment in regard to the best division to be made. The views are in accordance alike with those advanced ten years before by Fabre, and thirty years later by Surell. Of the vicinity of Embrun he writes,—“ In this magnificent basin Nature, has been quite prodigal of her blessings. The inhabitants have enjoyed her favours with their eyes shut ; they have slept on in the midst of her beauties. Ungrateful for all, they have inconsiderately carried the axe and the fire into these forests which shade the steep mountains—the ignored source of their riches. Soon were these emaciated peaks ravaged by waters, torrents swelled and precipitated themselves with fury on the plains; they have cut down, torn away, and undermined the foundations of the mountains ; grounds of great extent have been carried off ; others have been entombed ; these have been covered with rocks, those show nothing but stones and gravel. The ravages are still going on ; no obstacle is opposed to their fury—soon in Crevoux, Boscodon, Savines, and all the country around, the torrents will have utterly destroyed all this fine basin, which but lately would have borne comparison with all possessed by the richest countries—with the most fertile and the best cultivated of them all.” The warning was sounded in vain. It was drowned in the roar of cannon carrying into other lands devastation, and death, and mourning, and woe ; but after the men of that generation had mostly died away, and another generation had taken their place, the subject was again brought under consideration. In the Annales des Ponts et Chaussées, for 1833, 2d Semestre, is a paper by 60 LITERATURE ON TORRENTS. M, Montleuisant, entitled Mote sur les Deséchements, les Endiguements, et les Frrigations, which is:‘not without its bearing on the subject im hand. And about the same time a Memoir.by M. Delborgue Cormant, Ingénieur en chéf des Ponts et Chaussées, on erabankments. In 1834 appeared a second edition of a work previously published—His- toire, Topographie, Antiquites, Usages, Dialects, des Hautes Alpes—by J. C. F. Ladoucette, who had been prefect of the department, and who had been eulogised as the best prefect the High Alps ever had had. A statue of him erected in Gap speaks of the high estimation in which his labours for the good of the department were held. By him the number of basins, or river- valleys, in the High Alps is reckoned five, while by M. Héricart de Thury they had been reckoned eight, and by M. Surell they were afterwards, as we have seen, reckoned to be three; but, as has been stated, such enumera- tions are mere matters of judgment in regard to what are entitled to be considered separate basins, and to be entitled to this designation. This work did not contribute much information in addition to what was previously known on the particular aspect of the subject which connected it with forest science. It was otherwise with another work by one who had also held the office of prefect, a memoir, entitled Projet de boisement des Basses Alpes présenté a S. £., lé ministre secretaire d'etat de UV Interieur, par M, Dugied, ex-préfet de ce département. The following is a translation of a statement of his views :— “More than half of the department of the Low Alps is covered with arid and unproductive soils. These are increased by numerous torrents, which, descending there into the fertile valleys, complete the ruin of the country. “ Two causes have contributed more especially to bring about this sad state of things,—the destruction of forests on the one hand, and on the other the rage for clearing land by grubbing up the roots, and herbs, and bush. It is high time to apply remedies, for later to remedy the evil will have be- come impossible. . “To bring about a restoration of the department, three measures should be adopted—(1) To prevent additional grubbing, and to restore to the grubbed lands their primitive consistency ; (2) To plant the summits and sides of mountains with trees; (3) To enclose the torrents. We shall remark on each of these three measures in succession. “ First Measure.—Grubbings may be prevented by enforcing the ordinance of 1667, which pronounced a penalty of 3000 francs against all those who should grub ground free of wood on declivities. And grubbed lands may have their primitive consistency to some extent restored by compelling the proprietors to convert them into artificial meadows, be it by the power of the tribunals, or be it by administrative action. (The author cites an experiment, from which it appears that sowing the grounds with sainfoin, Hedysarum Onobrychis, had completely consolidated a land previously sub- jected to extensive waste). “ Second Measure.—lt follows, from statistical estimates, which have been prepared, that the area ofthe ground in the Low Alps, which we may hope to replant with trees with success, amounts to 150,000 hectares. It may be accomplished by each year taking of this surface from two to three thousand hectares, say 1200 acres, which it might be required of the pro- prietors of the soil to replant. But here there presents itself more of a difficulty. First, the great subdivision of the properties which will toultiply the cases of resistance, and the little revenue which the pro- DUGIED’S PROJET DE BOISEMENT. 61 prietors of each will draw from the plantations during the earlier years of their growth. And, secondly, it is the case that the gross expense of the plantations, will not on all grounds be compensated by proportionate future products. “ These difficulties are very serious, and they cannot be overcome but by one expedient, the intervention of the State. This may consist, Ist, in premiums given to the planters ; 2nd, in the gratuitous distribution of seeds ; and 3rd, in a remission of taxes in favour of the planters. “ A premium should be granted to every proprietor whose sowings have been successful. ©The verification of this must be made by a commission, and the success stated in a minute addressed by this commission to the prefect. The value of the premium might be 20 francs per hectare, and it should be paid by the State conjointly with the department, the State paying three-fourths and the department one-fourth of the amount. Thus, on the supposition of two thousand hectares being sown annually, the department would disburse each year in prizes 10,000 francs, and the public treasury would disburse in the same way 30,000. . . . Thegrounds on which I propose that the department should not pay more than 10,000 francs a year are, (1) that the department is far from being rich ; (2) that it will not recover payment of the sums it furnishes, whilst the Government will recover all its advances ; and (3) in a word, that without such advances on the part of the Government, there is no reason to hope that the operation will ever be carried out. No doubt the department will derive very great advantages from the work ; but the sacrifices which it will make to contribute to the success will not be the less real sacrifices.” . . . M. Surell says,— “ This, which was a weighty reason at the time when M. Dugied wrote these lines, has become, since the law of the 10th May, an absolute necessity.” M. Dugied goes on to say, “The second mode of intervention, consisting in the gratuitous supply of seeds, should be wholly at the expense of the State. Let us suppose that there are sown 2000 hectares annually, and that they are divided, in regard to kinds of trees, in the following way : 600 hectares in acorns ; 600 in beech ; 800 in firs and pines—in all, 2000 hectares. The whole expense of the seeds, carriage included, should be about 23,400 francs. The expense would rise to 35,100 francs if there should be sown 3000 hectares per annum instead of 2000. “The Administration, by delivering the seeds gratuitously, will have it in its power to determine that the different kinds of trees have been distri- buted with intelligence, and that each kind of soil has only received those for the growth of which it is best fitted. Declivities too steep should be sown with box trees and brooms, “The sowing will also require to be protected against cattle and against plunder. It will be necessary to secure a very active and very strict surveillance on the part of the forest officials, who may remain charged with watching the future forests ; their number should be augmented, their organization perfected, and at the same time their condition raised and their circumstances improved. “Tn conclusion, passing on to the third means proposed—the remission of taxes. Each proprietor, after an examination and approval of his sowings, at the end of five years might have a remission of taxes for the period of ten years. “Such are the sacrifices which impose themselves on the State to secure, by degrees, the reboisement of the mountains. 62 LITERATURE ON TORRENTS. “Third Measure.—This relates to the enclosing of the torrents by embankments. This enclosing should not be commenced until the forests shall have produced their effects—that is to say, in fifteen or twenty years after the first plantings. The engineers of roads and bridges should prepare the plans of the works to be executed. The expense should be borne by the proprietors interested, and by the State, which should assume the responsibility for half the outlay. The effect of the dykes should be at once to protect the river lands and to acquire new lands.” The author calculates that the enclosing of the Durance between Sisteron and the Pertuis des Mirabeau would cost at most from 4 to 5,000,000 francs ; and that the area of land acquired would be 10,000,000 square toises or fathoms, which would be worth, at the end of three years, at least 10,000,000 francs. The capital in this undertaking would thus be doubled at the end of three years. In a second division of the work, M. Dugied endeavours to show benefits resulting to the State from such undertakings, which might induce them to enter into this expenditure, doing it in such a way that the first expenses could not be in excess of the sums to be repaid. “The mortgage of the sums expended by the State,” he says, “ will resolve itself into an augmentation of the imposts to which should be subjected waste lands converted into forests. Strictly, and according to the rules adopted in the assessments of imposts, the augmentation should be for the advantage of the Department, and should lighten the manorial tax of the other proprietors. But it may be believed that the General Council will consent to the addition which may be made to the manorial contribution of the Department ; and it is on this augmentation, on the assumption of this consent, that we can base our calculations. “The contribution allotted to waste lands is upon an average twenty-two centimes per hectare ; that on forests is seventy-two centimes. When, then, a hectare of waste lands shall have been converted into forest, it will produce an augmentation of contribution equivalent to fifty centimes. It is this difference of fifty centimes which will constitute the funds for repayment. It must be observed that the fifty centimes will not be touched until ten years after the sowing, if the State have granted to the sowers a remission of taxation during this period of time. It must also be taken into account in the calculations that all the sowings will not be successful, and that a portion of the seeds delivered gratuitously by the Administration, and paid for by it, will have perished. It is supposed that the loss of sowings may be about a fifth of the whole. “From these data there can be formed tables which will give, year by year, a statement of the expenses, or of the returns, of the Government ; and it may be seen in this way that for a sowing of 20,000 hectares, the expenses of the Government at the end of ten years will have amounted to 534,000 francs, but that at the end of eighty-six years it will have recovered all these advances. Moreover, it will have acquired an annual bonus of 8000 francs, seeing that the contributions will continue to run on. “Tf one extends the calculations to 150,000 hectares (that is, to the whole of the area to be re-wooded), and if we suppose that the sowings will extend over fifty years, it will be found that the State will have recovered these advances at the end of one hundred and ten years, and that it will enjoy thenceforward an annual bonus of 60,000 francs. It follows from this that DUGIED’S PROJET DE BOISEMENT. 63 it is for the interest of the State to give to these operations the greatest extension possible. “Tt is also necessary that the State should recover the advances which it will have made for the construction of dykes. And it will find the means of liquidating the amount sunk in the work, first, in the profit calculated above, as resulting from the 50 centime augmentation of impost on the land as wooded, and further, in the proprietorship of a certain portion of the lands acquired. As it will have furnished the half of the expense to which the acquisition owes its existence, it is just that it should obtain possession of half of the lands acquired.” M. Surell says,— Such is the system developed by M. Dugied in his Memoir Sur le Boisement des Basses Alpes. This work produced no fruit. It did not for one moment stop the abuse. The Administration is not yet aroused from its indifference ; and the devastation of the torrents, and the miseries which this brings in its train, and the daily progressive ruin of the country, go on still, as in the past, before unpitying eyes. “The efforts of M. Dugied have been but little appreciated; and the country, in favour of which he was the first to raise his voice, has not been more just in regard to him than was the Administration of the Restoration which deposed him from the prefecture of the Basses Alpes, which he had not occupied more than a year, and where he would probably have rendered eminent services to the country. His-work has called forth ridiculing criticisms. They have referred the execution of his project to the Princes of the Arabian Night Entertainments. I must confess that the extravagancies of the project of M. Dugied has entirely escaped me. I only see in it an operation, sufficiently simple at bottom, which could not fail to develope, on a vast scale, what is practised every day by private parties ; an operation, the execution of which is evidently possible, and the expense of which has nothing surprising in it when I compare it with those which the Administra- tion entrusts every year to the engineer of the smallest arrondissement. Certainly, it would read as a romance, much more extravagant than the alleged palingenesique romance of M. Dugied, if one would turn over the leaves, mastering the same, of the report of the 120,000,000 francs worth of works executed every year, on all the bridges of France, under the Direction des pouts et chaussées! This speaks of the sea imprisoned in harbours, roads tunnelled through rocks, rivers confined by embankments or by bridges, lighthouses erected on rocks in the midst of tempests, canals trans- porting boats across the summit of mountains. I see in these works, works more difficult, more costly, and more marvellous by far, than the reboisement of some nooks of mountains. And if any come to discuss in the Chamber seriously, and like people who are ready to put hand to the work, the enormous budget of a milliard and a half, which certain economists tell us to be necessary for the establishment of a complete net- work of railways, what will be thought of this other prodigy, which was held to be only fabulous not more than thirty years ago? When we shall have multiplied by ten, or by a hundred, the figures given by M. Dugied, we shall not yet have come to expenses like to those of a great number of our public works, which are ten times—or, for that matter, a hundred times —less useful, and which do not frighten us, accustomed as we are, for a long time, to open our purses for their execution. “Will any one undertake seriously to deny the possibility of the reboise- ment proposed by M. Dugied? . . The proofs which have established 64 LITERATURE ON TORRENTS. this possibility are too numerous, too palpable, for this. Everybody admits that the Alps were wooded long ago; and this is itself a proof that woods may yet be made to reappear there. The first forests which nature cast on these mountains had to clothe a soil more naked, more sterile, more irregular, than the actual soil of the present. And if vegetation has already triumphed a first time in this struggle against destructive agents, why should she succumb to-day? It will be said that she was assisted by time! It is so. But to-day she will be assisted by man, and that assistance, in my opinion, avails more than that of some four centuries. There are here and there, in the bed of the Durance, conquests over the waters made by the effort of nature alone ; but long ages have scarcely sufficed to ensure vegetation there, ‘and some portions of it remain eternally sterile. When man undertakes like conquests he finishes them in three years ; three years suffice for him to make fields to flourish on the very place where the waters rolled pebbles and barrens sands. This miracle is renewed every day, and under the eye of all. Is not this a more marvellous triumph than it would be that man should succeed in reforesting lands which, for the most part, have been covered with forests before. “Tf I wished to criticise the work of M. Dugied,” says he, “I would not bring against him such objections. But whilst entirely approving the basis and the end of the project, I would condemn some few details of execution. M. Dugied has comprised, under the designation of torrents, the Durance, the Verdon, the Cleone, which are rambling rivers, and on which the reboisement of the mountains could only have a detournée, and secondary influence in affecting the water-course. And in making the embankment of these water-courses a corollary of the plantation of forests, he has coupled together two distinct operations. From this it follows that his project is in some respects too ample and exaggerated, and at the same time in some measure defective. And this impression of vagueness is deepened when it is seen that M. Dugied does not attach to forests any action on the torrents other and beyond that effected by a climatal change. As this influence is rather uncertain, and very difficult to be cleerly demonstrated, one cannot understand how the author came to build on it such great expectations, and that he should make of reboisement a preliminary operation, without which the embankment of rivers would not be undertaken with success. “ But there is a point in which his project seems to me defective in its very foundation—it is this, he makes the execution of it to rest entirely on the gooodwill of the proprietors. If the enterprise be really a thing of public utility, as the author says it is—if it truly have the degree of importance and necessity which he attributes to it—how does he come to leave it at the mercy of the first peasant—stupid or stubborn—who willl refuse to take part in it? It showed little knowledge of the spirit of the inhabitants of the country, to believe that a premium will suffice in every case to overcome the natural apathy, and above all, the obstinacy of such, if once they stubbornly determine not to give in to the undertaking. Now, this will certainly occur oftener than once, if it do not become even generally the case. The twenty francs of premium per hectare, which M. Dugied tenders to them, would not always appear to them a sufficient indemnity to com- pensate the trouble which the sowings might entail, and the loss of their pastures, of which M. Dugied says nothing, and of the numerous interferences which will follow from the operation. These works, besides, will not succeed but through the expenditure of sustained and intelligent exertions, PUGIED AND SURELL, 65 which the peasants will not make. They. will soun have invented a thousand artifices to gain the premiums, without having done anything to deserve them. “It is thus indispensable that the State undertake the charge not only of the expense, but also the execution of the works; and ex-appropriation or con- fiscation will furnish them with a legal means to bring down all possible resistances. “Tt seems that M. Dugied has recoiled from urging this, most possibly be- causé he was afraid of the expense; but I have shown that this will be some- what reduced. Besides, does not the State acquire every day for roads, and by the same means, fields far more costly than the waste lands of these moun- tains? And in that case the possession of the soil brings to her nothing, or at least procures for her only a change of advantages. Here it buys the lands at a low price, it exploits them, it gives them value, and by that means she increases her domain if she retains them in her own hands, or the revenue from the taxes if she restores them to the inhabitants.” Of this work of M. Dugied, Surell says,—‘ It is the only memoir known to me which treats specially of the means to be employed to counteract and oppose the scourge of the torrents.” And he adds,—‘‘ What is proposed by M. Dugied is conceived in a comprehensive spirit ; but the characteristic peculiarities of the torrents are neither analysed nor described by him ; the work is addressed to those to whom the torrents are already perfectly known.” In 1841 appeared his own work, Etude sur les Torrents des Hautes Alpes, of which a résumé has been given in Part I. of this compilation. On my first perusal of this work, knowing as I did how much damage was done by torrential floods at the “Cape of Good Hope, my feeling was a desire that I could make the substance of it my own, and give forth anew the observations, and the reasonings, and conclusions of the author, for the information of my former compatriots in that Colony, and of others in other lands exposed to such torrential floods as there alternate with severe and long-continued droughts. But this was impossible ; and, moreover, I have often found excerpts from the work of an original ‘thinker far more satis- factory, and often far more suggestive, than any digest of it given by friend or foe. Often, on reading some such digest, I have felt disposed to cry out, Give me his own words, for no words can better tell what he says than the words he has himself used in the collocation of them which he has given ! but to do this was also impossible ; and I have done what I consider most likely to be satisfactory at once to M. Surell and to students of the subject of which he treats, at the Cape or in other lands, in which the English language must be the medium of communication. The work was published by order of the Administration des Ponts et Chaussées. Public opinion was not then so advanced on the subject as to prompt to action, and his services were put in requisition for the carrying out of the system of railways, which seemed to demand more immediate attention. While rejoicing in his honours and usefulness as Ingénieur en chéf des Ponts et Chaussées, and Directeur des Chemins de fer du Midi, some regret may be felt by those who are alive to the importance of reboisement as a means of stifling torrents that scope was not found for his energies in originating and carrying out works such as he had advocated. After the work was out of print, many solicitations were addressed to him F 66 LITERATURE ON TORRENTS, to issue a new edition. But from this he shrunk. The state of things depicted by him had, to a great extent, ceased to be, his suggestions had been carried into effect, and a new state of things had come into being. But he was relieved of embarrassment by his comrade and friend, M. Cézanne, agreeing to prepare a supplemental volume, and the two were published conjointly,—the first volume, the Etude of M. Surell, in 1870, and the Supplement, by M. Cézanne, in 1872. The subjects of M. Surell’s study were chiefly these,—the phenomena of torrents and effects produced by them; the causes of their occurrence ; means of defence which had been employed to protect the land and its inhabitants against their ravages ; and measures which were more likely to prove efficient if they should be employed, which measures were plantations of trees, and herbage, and bush, over the area drained by them, combined with the erection, in subordination to this, of barrages, or wears, to control and regulate the flow, where this may be practicable and desirable. Previously to the publication of the original edition—but at what date I know not—there had been published a Memoire sur [état des foréts dans les Hautes Alpes, les causes de cet état, ses resultats et les moyens dy remedier, by M. Delafont. Of this M. Surell writes,—‘ All the causes of the destruction and disappearance of forests are thoroughly and carefully expounded in a memoir by M. Delafont, inspecteur des eaux et foréts—a memoir full of well-intentioned and wise statements, which only calls forth regret that it did not inspire the Adminstration with enlarged and bold views, which alone would be commensurate with the evil; for great evils call for great remedies.” “The sad results which I am about to point out,” says M. Delafont, “ are deplorable on all hands. All men who have not been blinded by ignorance, or whose heart has not been withered up by selfishness, give expression to the thought that it is high time to stop the progress, ever increasing, of so fearful a devastation. They lament over the evils without number which are occasioned by the deforesting of the mountains, and seem to call us to the protection of our forest wealth. These reflections, these prayers, I have often myself heard uttered with an energy which is inspired by the profound conviction of the existence of a great evil, and of the imperious necessity which there is to stop its course. Let us listen to the cries of distress of a population alarmed by the future before it.” And M, Surell refers to this, and other statements by M. Delafont cited by him, as supplying evidence that he had himself in no way exaggerated the evil in what he said in his Etude sur les Torrents. While the work of M. Surell’s was passing through the press, he received a copy of a Memozre sur la dégradation des foréts dans les arrondissements @Embrun, et de Briancon, which the inspector of forests, in these two arrondissements, M. Jousse de Fontaniére, had shortly before addressed to the Administration, Of this he says,—“This work—prepared by a man most competent for the work, and devoted to his duties, who, after having struggled for a long time against the innumerable difficulties of his service, succumbing under the trial, took measures at last to demand aid—should have had the effect of securing the attention of the State to the frightful future to be anticipated in this department.” And he cites the following as a specimen of the out-spoken faithfulness of MEMOIRE BY JOUSSE DE FONTANIERE. 67 the author,—“ From all that has been said, it is concluded that the depart- ment of the High Alps is the one of all France in which the cultivators are most threatened in théir fortune, and that they will be compelled, sooner than is supposed, to abandon the places which were inhabited by their fore- fathers, and this as a consequence of the destruction of the soil, which, after having supported so many generations, has given place, little by little, to sterile rocks. “The destruction of the forests will be the principal cause of this calamity. The disappearance of these from the mountains will give up the soil to the action of the waters, which will sweep it away into the valleys ; and then the torrents, becoming more and more devastating, will bury under their alluvial deposits extensive grounds, which will be for ever with- drawn from agriculture. “The crusts, denuded of their vegetable soil, no longer permitting the infiltration of the waters, these will flow away rapidly on the surface of the ground. Then the springs will dry up; and the drought of summer being no longer moderated by their irrigations, all vegetation will be destroyed. “The elements of destruction growing thus one out of another, we have only to observe what passes to-day to predict what will infallibly come about some ages hence. When the forests shall have entirely disappeared, fuel and water, the two primary necessaries of life, will be awanting in these desolated countries. “The cupidity of the inhabitants of these mountains, the tenacity with which they keep to old customs, do not permit a hope that a moral conviction of this desolating future will strike their thoughts so strongly as to lead them to make some temporary sacrifice ; it is, therefore, for the Administra- tion, more enlightened in regard to the state of things, and to their con- sequences, to meet the evil by laws most appropriate to the requirements of the country.” Ladoucette, in his Histoire, Topographie, Antiquités, Usages, Dialectes des Hautes Alpes, already cited, says the peasant of Dévoluy “ often goes a distance of five hours, over rocks and precipices, for a single [man’s] load of wood ;” and that “ the Justice of Peace of that Canton had, in the course of forty-three years, but once heard the voice of the nightingale.” Now the desert and the solitary plain begins there anew to flourish like a rose, and the inhabitants to rejoice with joy and singing ; and there is heard the shout of children playing in the streets—a change brought about by reboisement and gazonnement, confirming the conclusion that the destruction of trees and herbage had been the occasion of the desolation. In regard to the valley of Embrun, where a corresponding improvement has been brought about by similar means, Héricart de Thury, who has also been already cited, wrote in 1806,—“ In this magnificent valley nature had been somewhat prodigal of its gifts, Its inhabitants have blindly revelled in her favours, and fallen asleep in the midst of her profusion.” And Becquerel, in his work Des Climats, mentions also that it was once remark- able for its fertility. What it became, through the ravages of torrents, after the destruction of its trees, Surell has shown. M. Surell cites, as in accordance with his views in regard to the influence of the climate on the formation and violence of torrents, the following remarks by Labéche, in his treatise on Geology. Writing of the geology of the Alps, M, Labéche says,—“ A difference in the climate ought to produce 68 LITERATURE ON TORRENTS. other visible changes, as well in the superincumbent rocks as in those that were of an older formation. It is probable that the more a climate was warm, and approached that of the tropics, the greater would be the evapor- ation, and the quantity of rain; greater also would. be the intensity of power of certain meteoric agents ; consequently, according to this hypothesis, the different deposits ought to present indications of the influence of such climates, more marked in proportion as the epoch in which they were formed was more remote from the present. Ifrains, like to those of the tropics, have fallen on high mountains such as the Alps—even supposing that many of them had an elevation less than that of these—these rains would produce effects very different from those which we see now in the same countries ; one may see that these would form all at once torrents of which the actual inhabi- tants of these mountains have no idea ; such volumes of water would sweep away quantities of detritus far greater than those which the actual torrents of the Alps carry away, the volume of which, however, is pretty considerable, “Thus, though admitting the correctness of this hypothesis in this, it is necessary always to take into account the differences produced on the sur- face of the earth by the action of meteoric agents, the which is more power- ful as the climate is more warm. One ought especially to give attention to this, when from the observation of a series of the layers of the same district it appears evident that the temperature, under the influence of which they were formed, has gradually diminished. Let us examine now to what degree vegetation can, in warm climates, counterbalance the power of dis- integration, and transport which atmospheric agents possess. It appears that, all other circumstances being equal, the more warm a climate is, the more vigorous is the vegetation which it produces. The question then comes to this: Does the vegetation protect the soil against the destructive action of the atmosphere? It is impossible to answer this otherwise than in the affirmative. If we want proofs of this fact we shall find them in the artifical mounds, or barrows, which are so common in many parts of England ; they had been exposed in that climate to the action of the atmosphere for about 2000 years; and yet they have not undergone, in their form, any perceptible change, although they have, during at least a considerable portion of that time, only been covered by a light layer of turf. If now it is admitted that the vegetation protects, to some extent, the ground which it covers, it follows that the stronger the vegetation is the more efficacious is the protection which it affords, and as a consequence the ground is always defended from the destructive action of the atmosphere in proportion to the need it has of such protection. Without this providential law of nature the softer rocks of tropical regions would be speedily carried away by the waters, and the soil would no longer be able to sustain vegetables or animals ; for, although in many tropical regions we meet with vast extents of land which present the appearance of sterile deserts, but which one sees suddenly start to life after two or three days’ rain, and cover themselves, as by enchantment, with a beautiful verdure, we should bear in mind that the roots of the briskly vivacious plants from which moisture causes to be produced 8o vigorous a vegetation—and even those of the annual plants which have passed away, of which the seeds produce leaves so verdant— interlace themselves in such a way in the soil that they oppose a consider- able resistance to the destructive power of rain. In the Savannahs of America it is frequently the case that there is little vegetation, and there they experience considerable disintegration, ; LABECHE AND MICHEL CHEVALIER, 69 “T have by no means the intention to infer from what has been said that the disintegration of soil is not generally greater under the tropics than in temperate climates ; it has been my desire simply to establish that in both cases the soil receives, from the vegetables which cover it, a pro- tection proportionate to the destructive influence to which it is exposed. Let’ us suppose that there should occur in England one of those rainy seasons so common under the tropics. No doubt.great extents of land would be washed away, and the barrows, of which we have already spoken, would quickly disappear. If, on the contrary, there fell there only the same quantity of rain which we have every year in the climate of England, we would find scarcely any traces of vegetation in the low-grounds, for the water produced by it would be insufficient to sustain tropical plants, and while it tended to disintegrate the soil, it would be so speedily evaporated that its destructive action would be scarcely perceptible. The quantity of rain and the vegetation are proportionate to one another; nevertheless, the disintegra- tion of the soil increases with the quantity of rain, and the force of many meteoric agents, in such a way that, other things being equal, the greater the rainfall the greater is the destruction of the soil ; and consequently, the warmer the climate, the more considerable is the disintegration of the mountains. “In tropical regions, parasitical and creeping plants are seen in all directions, growing wherever it is at all possible to do so, and with such luxuriance as to render the forest almost impassable. The forms and the leaves of trees, and of such plants, are admirably adapted to resist great rains, and to protect the innumerable creatures which, in the rainy season, come to seek a shelter under their foliage. The noise which the tropical rains make in falling on these forests strikes strangers with astonishment ; it is heard at distances which would be almost incredible to the inhabi- tants of temperate regions ; and the rain, thus deadened and broken in its fall, is speedily absorbed by the soil ; whereas, where it flows into hollows, it produces torrents, which every one must confess are rather impetuous, and cause great ravages.” M. Michel Chevalier, in his work entitled Des Interets Matériels de la France, writes thus :—“ Besides the works executed in the river-bed, there are other measures which, according to men of experience, would exercise a salutary influence on the navigability of natural water-courses, and which concern even canals, as to feed these recourse must be had to rivers and to the smallest streams. I wish to speak specially of the replanting of moun- tains which have been so improvidently despviled of their woods, and abandoned in their nakedness by a culpable indolence, or even by a fatal one, descending to niggardly interests, which the law does not recognize, but on the contrary resents, have hindered the forests from reproduction by the effort of nature alone. The rains and the snows, when they fall on the bald heights, flow away or evaporate with the greatest rapidity ; in place of maintaining brooks and rivers, on the rich levels, by which boatmen may profit, and on which the proprietors of river-banks may felicitate themselves, they produce there sudden floods, inundatious which suspend navigation, devastate pro- perties, covering them with gravel, and sometimes cating into them and carrying them away ; then, after these floods, there follow soon low waters, which only stop at distant points and for a short time after some storm, Through reckless deforesting our temperate countries are thus being agsimi- 70 LITERATURE ON TORRENTS. lated to southern regions, where there are nothing but torrents during the spring and autumn, imperceptible threads of water in the midst of an ocean of sand during the summer, and never smooth unmanageable rivers. The business is now to restore the soil of France to the primitive forests. Amongst the deforestings effected within the last fifty years there is much which will be permanently profitable to the country. Deforesting is a conquest of man over nature ; woods ought to disappear from the plains, and there to give place to cultivation. But, unhappily, we do not find in the valley alone ground furrowed by the plough, or lands furnishing pasturage and grass; they have plucked up the trees of sterile cantons, where wood alone should grow ; they have imprudently given up to the axe the sides and the summits of our mountains; then the régime of the profitless pastures, freed from all surveillance, together with a vicious administration of public and private forests, have hindered the reproduction of wood after the felling ; and the carelessness of the agents of the State in the communes have shut their eyes to the most destructive abuses. To-day the communes and the State possess thousands—millions of hectares of nominal forests, where there is just as much vegetation as there is in the steppes of Tartary, or in the desert of Sahara, The sowing ordered by the laws, or by the regulations, have been rendered illusory through the amount of the grants which were allotted to them, and a mockery through the bad faith which has too often presided over their execution, We are assured that oftener than once, and that I may say at a time not very remote from the present, the lessees of the fellings of the woods have sown sand instead of seed. About twenty years ago the evil came to a head ; then the Administration established the Forest School at Nancy, which furnished workmen capable and active, and men of integrity. In 1837 the minister of finances proposed to stimulate the zeal of subaltern agents by an improved treatment, which placed them above misery, and protected them from temptation. All these improvements of the officials are doubtless to be commended, but they will be productive of little effect so long as there is not inserted in the budget a chapter in support of replanting. With a million devoted every year to sow and plant well-selected kinds of trees on the plots occupied by the forests, which would appear always to rebel against cultivation, the State would create in twenty or thirty years an immense eapital, spread over the vast brows of the Pyrenees, of the Alps, and of the Vosges; as well as on the shores of the lands where they have applied, only on a Lilliputian scale, the ingenious and economic process of the savant Bremontier. In time of peace this would be an inexhaustable provision for twenty branches of industry, and notably for that in iron, which will never be wrought cheaply in France until wood shall be more abundant. In time of war this would be a resource of more ready avail than that of new taxes.” In the Memoires de ? Academie des Sciences Morales et Politiques for 1843 there appeared a Memoire sur les Populations des Hautes Alpes, by M. Blanqui, an eminent political economist, from which the following passage is cited and translated by the Hon. George P. Marsh, in his valuable work entitled The Earth as Modified by Human Action :—*TI do not exaceerate.” says Blanqui. “When I shall have finished my description and designated localities by their names, there will rise, I am sure, more than one voice from the spots themselves, to attest the rigorous exactness of this picture of their wretchedness. I have never seen its equal even in the Kabyle villages BLANQUI'S MEMOIRE, 71 of the province of Constantine ; for there you can travel on horseback, and you find grass in the spring, whereas in more than fifty communes in the Alps there is absolutely nothing. “The clear, brilliant, Alpine sky of Embrun, of Gap, of Barcelonette, and of Digne, which for months is without a cloud, produces droughts interrupted only by diluvial rains like those of the tropics. The abuse of the right of pasturage and the felling of the woods have stripped the soil of all its grass and all its trees, and the scorching sun bakes it to the consistency of porphyry. When moistened by the rain, as it has neither support nor cohesion, it rolls down to the valleys, sometimes in floods resembling black, yellow, or reddish lava, sometimes in streams of pebbles, and even huge blocks of stone, which pour down with a frightful roar, and in their swift course exhibit the most convulsive movements. If you overlcok from an eminence one of these landscapes furrowed with so many ravines, it presents only images of desolation and of death. Vast deposits of flinty pebbles, many feet in thickness, which have rolled down and spread far over the plain, surround large trees, bury even their tops, and rise above them, leaving to the husbandman no longer a ray of hope. One can imagine no sadder spectacle than the deep fissures in the flanks of the mountains, which seem to have burst forth in eruption to cover the plains with their ruins. These gorges, under the influence of the sun which cracks and shivers to fragments the very rocks, and of the rain which sweeps them down, pene- trate deeper and deeper into the heart of the mountain, while the beds of the torrents issuing from them are sometimes raised several feet in a single year, by the débris, so that that they reach the level of the bridges, which, of course, are then carried off. The torrent-beds are recognized at a great distance, as they issue from the mountains, and they spread themselves over the low grounds, in fan-shaped expansions, like a mantle of stone, sometimes ten thousand feet wide, rising high at the centre, and curving towards the circumference till their lower edges meet the plain. “Such is their aspect in dry weather. But no tongue can give an adequate description of their devastations in one of those sudden floods which resemble, in almost none of their phenomena, the action of ordinary river-water. They are now no longer overflowing brooks, but real seas, tumbling down in cataracts, and rolling before them blocks of stone, which are hurled forward by the shock of the waves like balls shot out by the explosion of gunpowder. Sometimes ridges of pebbles are driven down when the transporting torrent does not rise high enough to show itself, and then the movement is accompanied with a roar louder than the crash of thunder. A furious wind precedes the rushing water and announces its approach. Then comes a violent eruption, followed by a flow of muddy waves, and after a few hours all returns to the dreary silence which at periods of rest marks these abodes of desolation. “The elements of destruction are increasing in violence. The devastation advances in geometrical progression as the higher slopes are bared of their wood, and ‘ the ruin from above,’ to use the words of a peasant, ‘helps to hasten the desolation below.’ “The Alps of Provence present a terrible aspect. In the more equable climate of Northern France, one can form no conception of those parched mountain gorges where not even a bush can be found to shelter a bird— where, at most, the wanderer sees in summer here and there a withered lavender—where all the springs are dried up—and where a dead silence, 92 LITERATURE ON TORRENTS, hardly broken by even the hum of an insect, prevails. But if storm bursts forth, masses of water suddenly shoot from the mountain heights into the shattered gulfs, waste without irrigating, deluge without refreshing the soil they overflow in their swift descent, and leave it even more seared than it was from want of moisture, Man at last retires from the fearful desert, and I have, the present season, found not a living soul in districts where I remember to have enjoyed hospitality thirty years ago.” And in another connection it is said by Mr Marsh,—“ It deserves to be specially noticed that the district here referred to, though now among the most hopelessly waste in France, was very productive even down to so late a period as the commencement of the French Revolution. Arthur Young, writing in 1789, says,—‘ About Barcelonette, and in the highest parts of the mountains, the hill-pastures feed a million of sheep, besides large herds of other cattle ;’ and he adds,—‘ With such a soil’and in such a climate, we are not to suppose a country barren because it is mountainous. The valleys I have visited are, in general, beautiful.’ He ascribes the same character to the provinces of Dauphiny, Provence, and Auvergne, and, though he visited, with the eye of an attentive and practised observer, many of the scenes since blasted with the wild desolation described by Blanqui, the Durance and a part of the course of the Loire are the only streams he mentions as inflicting serious injury by their floods. The ravages of the torrents had, indeed, as we have seen, commenced earlier in some other localities, but we are authorized to infer that they were, in Young’s time, too limited in range, and relatively too insignificant to require notice in a general view of the provinces where they have now ruined so large a proportion of the soil.” But the voice of warning fell on deaf ears. It was like a voice crying in the wilderness—not the voice spoken of by the Hebrew seer, powerful as was that which had said,—“ Let there be light,” and which like it brought about its own accomplishment—but a voice crying in the wilderness, as that expression is generally understood. Inundations in 1840, and others occurring in 1846, caused some attention to be given to the subject, and measures were about to be adopted, with a view to prevent the continued occurrence of such catastrophes, when the Revolution of 1848 took place, and forests were sacrificed right and left to provide funds required to meet the national expenditure of the day. But on the establishment of the empire the subject again commanded attention. And within the last twenty years several works, in this department of the literature of forest science, have followed each other in quick succession. “In 1853, ten years after the date of Blanqui’s memoir,” says Marsh, “M. de Bonville, prefect of the Lower Alps, addressed to the Government a report in which the following passages occur :— “*Tt is certain that the productive mould of the Alps, swept off by the increasing violence of that curse in the mountains, the torrents, is daily diminishing with fearful rapidity. All our Alps are wholly, or in large pro- portion, bared of wood. Their soil, scorched by the sun of Provence, cus up by the hoofs of the sheep, which, not finding on the surface the grass they require for their sustenance, gnaw and scratch the ground in search of roots to satisfy their hunger, is periodically washed and carried off by melting snows and summer storms. ‘“<¢] will not dwell on the effects of the torrents. For sixty years they DE EBONVILLE AND BELGRAND. 73 have been too often depicted to require to be further discussed, but it is important to show that their ravages are daily. extending the range of devastation. The bed of the Durance, which now in some places exceeds a mile and a quarter in width, and, at ordinary times, has a current of water less than eleven yards wide, shows something of the extent of the damage. Where, ten years ago, there were still woods and cultivated grounds to be seen, there is now but a vast torrent; there is not one of our mountains which has not at least one torrent, and new ones are daily forming. «* An indirect proof of the diminution of the soil is to be found in the depopulation of the country. In 1852 I reported to the General Council that, according to the census of that year, the population of the department of the Lower Alps had fallen off no less than 5000 souls in the five years between 1846 and 1851. “Unless prompt and energetic measures are taken, it is easy to fix the epoch when the French Alps will be but a desert. The interval between 1851 and 1856 will show a further decrease of population. In 1862 the ministry will announce a continued and progressive reduction in the number of acres devoted to agriculture ; every year will aggravate the evil, and in half a century France will count more ruins, and a department the less.’ “Time has verified the predictions of De Bonville. The later census returns show a progresssive diminution in the population of the departments of the Lower Alps, the Istre, Drome, Ariége, the Upper and the Lower Pyrenees, Lozére, the Ardennes, Doubs, the Vosges, and, in short, in all the provinces formerly remarkable for their forests. This diminution is not to be ascribed to a passion for foreign emigration, as in Ireland, and in parts of Germany and of Italy ; it is simply a transfer of population from one part of the empire to another,—from soils which human folly has rendered unin- habitable, by ruthlessly depriving them of their natural advantages and securities, to provinces where the face of the earth was so formed by nature as to need no such safeguards, and where, consequently, she preserves her outlines in spite of the wasteful improvidence of man.” Mr Marsh adds in a foot note,—* Between 1851 and 1856 the population of Languedoc and Provence had increased by 101,000 souls. The augmenta- tion, however, was wholly in the provinces of the plains, where all the principal cities arefound. In these provinces the increase was 204,000, while in the mountain provinces there was a diminution of 103,000. The reduction of the area of arable land is perhaps even more striking. In 1842 the department of the Lower Alps possessed 99,000 hectares, or nearly 245,000 acres, of cultivated soil. In 1852 it had but 74,000 hectares. In other words, in ten years 25,000 hectares, or 61,000 acres, had been washed away, or rendered worthless for cultivation, by torrents and the abuses of pasturage.—Ciave, Etudes, pp. 66, 67.” In the Annales des Ponts et Chaussées for 1854 is a paper by M. Belgrand, entitled De [Influence des Foréts sur Cécoulment des eaux pluviales, cited by Mr Marsh as containing notices of remarkable floods occurring in different rivers in France. The Loire, above Rouen, has a basin of 2417 square miles, and in some of its inundations it has delivered 9500 cubic yards per second, which is 400 times its low-water discharge. And he gives a list of eight floods of the Seine, occurring within the last two centuries, in which it has delivered 3000 cubic yards per second, or 30 times its low-water G 74 LITERATURE ON TORRENTS, discharge. Such is the vastness of the body of water rapidly poured into the rivers by torrents or storms of rain, by which torrents are occasioned. In 1857 appeared Etudes sur les Inondations, leur causes et leur effets by M. F. Vallés, in which he makes several comments on the observations of Belgrand, relative to the rainfall in 1852 at Vozelay, in the valley of the Beuchat, and at Avallon, in the valley of the Grenetiére. And in the Annales Forestiéres, for the December of the same year, appeared a paper, entitled Les Inondations et le livre de M. Valles, by A. F. D. Héricourt. “The udometric measurement of Belgrand, discussed by Valles, consti- tute,” says Marsh, “ the earliest, and in some respects the most remarkable, series known to me of persevering and systematic observations bearing directly and exclusively upon the influence of human action upon climate, or, to speak more accurately, on precipitation and natural drainage. The conclusions of Belgrand, however, and of Valles, who adopts them, have not been generally accepted by the scientific world, and they seem to have been, in part at least, refuted by the arguments of Héricourt, and the observations of Cantegril, Jeandel, and Belland.” These will be found quoted in Comptes Rendus aU Academie des Sciences, 1861. In 1856 appeared a pamphlet, published in Paris, entitled Moyens de Jorcer les torrents des Montagnes de rendre une partie du sol qwils ravagent, by UM. Rozet, to which I shall afterwards have occasion to refer more in detail. And in the course of this year—whether before or after the appear- ance of M. Rozet’s pamphlet I have not been able to ascertain—renewed inundations supplied a befitting opportunity for the Emperor to call the attention of the nation to the subject. In the following year (1857) was published La Provence au point de vue des Bois des Torrents, et des Inondations, par Charles de Ribbe. Some of the facts, historical and statistical, embodied in this work are embodied in a notice of Dauphiny and Provence, by Marsh, which will afterwards be cited. In a work by Maurice Champion, entitled Les Inondations en France depuis le VIme Siécle jusyia nos jours, a work in six volumes, published in Paris, 1858-1864, are narrated the ravages of many inundations which have devastated extensive districts. And in an erudite and able work by Alfred Maury, entitled Les Foréts de la Gaule et de Vancient France, published in Paris in 1857, is collected an immense amount of statistical detail, on the extent, the distribution, and the destruction of the forests of France. By help of these the student in this department of Forest Science can carry back his studies to times that are past. In 1858 appeared Htude sur les Phenomenes et la Legislation des Eaux au point de vue des Inondations, par A. Monestier Lavignot. The same subject is discussed in a Rapport sur les Plantations de la Solonge, by M. A. Broignard, de l'Institut, which appeared in Annales Forestiéres, Tom. X.; and in a report to the Emperor by His Excellency M. Magne, the Minister of Finance, relative to the planting of mountain ranges with trees, which appeared in the Moniteur of February 3, 1860. This will afterwards be given in full. ; In this year (1860) was published a Memoire sur les Inondations des Rivieres de VArdéche, by M, de Mardigny ; and in the year following (1861) LADOUCETTE AND DELBERGUE-CORMANT. 75 appeared a pamphlet, published in Paris and Toulouse, entitled Ftudes sur le Reboisement des Montagnes, par Paul Tray. During the years which followed much information was collected through enquiries made by the Government, the substance of which was embodied in documents issued in connection with the legislation which was now employed to give effect to the suggestions which had been made, and the results were to some extent embodied in that legislation; and a good deal more was learned in connection with practical operations which were being carried on, which was embodied in reports of operations and reports of conferences held by appointment of the Administration by the officials and others employed in the work, which were published by the Administration. Translations of most of these documents will afterwards be given. But it may be mentioned here that to meet public opinion it was deemed expedient, as the work advanced, to give more attention to gazonnement than was done in the commencement of the operations begun. In the citations which have been made from works previously published, one section only of the literature of Forest Science—that relating specially, if not exclusively, to the influence of forests on torrents—has been laid under contribution. In regard to that I may say, in a word, that the French literature in this department of Forest Science is saturated with the idea that vegetation is the natural protection of the ground from the consequences of meteorological disturbances, occasioned by the destruction of forests by which a meteorological equilibrium, favourable to agricultural operations, had been established, and which may be re-established by the restoration of sylvan clothing to the mountains; and the same idea permeates much of the literature of France on subjects allied to that to which I have referred. But, while primary importance was attached to reboisement and to gazonne- ment, mechanical appliances, such as Surell sought to combine, when necessary, with the extension of vegetation as a means of bridling, and stifling, and controlling torrents, did not fail to command the attention of those who were interested in the struggle, which was the more necessary that there are destructive torrents produced by the melting of snow, and. the rapid melting of glaciers, or by débdcles, the breaking up of icy barriers confining waters, in situations in which rebotsement and gazonnement are impracticable, and therefore as a remedy inapplicable ; and there are other torrents of which the same thing, or something similar, may be alleged in regard to these appliances. There is given by M. de Ladoucette an exposition of a scheme of embank- ment proposed by M. Delbergue-Cormant, Ingénieur en chéf des Ponts et Chaussées. The following is a translation of the memoir by M. Delbergue- Cormant, cited by him :—“ There are two kinds of torrents, principal and secondary. The first are easily distinguished,—they always flow in the principal valleys; thus the Durance, the Guil, the Deux-Briich, the Drac, é&c., are principal torrents. “The second descend from the lateral mountains of the valley, and come often at an angle more or less approaching 90°, to increase the principal ‘torrent, which occupies the depth of the valley; it follows from this that the torrents of Sarrazin, of Boscodon, are secondary torrents. The means employed hitherto to control the principal torrents are to enclose them by 76 LITERATURE ON TORRENTS. banks faced with stones. I have shown in another memoir that one may obtain the same results more economically ; but wishing to occupy myself at present only with secondary torrents, I confine myself to this. ‘Before proposing means of preventing or of repairing the ravages which the secondary torrents make, it is necessary to know these torrents, and for this purpose to take them up at their birth, to examine them in their course, and in following them in the increase of their bed of deposit year by year to show the enormous extent of the damage which they may have occasioned. It is certain that a secondary torrent does but little or no evil so long as it is shut up between steep banks. It is when it leaves the lateral mountains to enter into the valley that it begins its ravages. Let us examine how this comes about. “So long as the waters of a torrent are confined within steep banks they roll on in a great body, drawing on with them not only gravel, but even enormous rocks, Scarcely have they left the mountain, when, not being sustained and kept together by the banks, they divide themselves into a thousand little currents; and then, so far from drawing on rocks, they scarcely roll gravel along, and as their force diminishes more and more they scarcely bear along to the principal torrents some grains of sand. This explains perfectly the form taken by the deposits formed by secondary torrents. At the departure from the mountain this form is that of a portion of a cone, the summit of which corresponds to the point where the torrent comes out from the mountain. In effect, the waters, in quitting the mountain, have still an acquired force which permits them to roll the rocks on to some dis- tance ; in the second instance, this force being diminished, they deposit the rocks and carry forward only stones ; in the third instance, their force being still further diminished, they abandon the stones and then carry on the gravel. Thus, then, is formed a first deposit, which will be less and less considerable in proportion to its distance from the mountain. In a second flood of the torrents the waters get freely away, and the deposits of sand and of gravel will increase less, always in this following a slope. In fine, the increase may become so inconsiderable that the sides of the cone recede from the mountain ; then the torrent divides itself into two currents, and soon there comes to pass, at each of these two currents, what had occurred with the principal currents. Thus the fertile lands of the valley may disappear under the heaps of stone and of sand ; as these torrents are greatly multi- plied, there will come a day that their deposits, spreading out till becoming conjoined, a whole valley will become sterile, and will not be able longer to support its inhabitants, “We have seen that the secondary torrents do not deposit the gravel and stones which they carried from the mountain ; but when their waters are no longer confined by the banks—when they enter the valley—they spread themselves over a great surface, and thus lose their force 5 they cannot carry further the stones and the gravel, and these they abandon at a greater or less distance from the mountain. This indicates to us the course to be followed in order to control these torrents at their embouchure, and to prevent them covering the land with gravel. “T would propose, then, in accordance with this principle :—First, to dig a bed for the torrent in the deposit which has penetrated to the exit from the mountain ; second, to give little breadth to this bed, but great depth, in order that the waters may be there confined as they are in the natural bed which the torrent has dug for itself in the mountain, and that they may MEMOIRE BY DELBERGUE-CORMANT, 17 continue to sweep on the stones and gravel ; third, to carry the gravel which is dug out from these cuttings to some distance from the edge, to form of them two embankments parallel to the new bed ; fourth, to widen the entry of the new bed at the end towards the mountain, in order to collect the waters, and to strengthen by large stones these widened portions; fifth, to plant the embankments with willows, and other trees which grow quickly ; sixth, to take care to clear away the obstructions which may form them- selves in the new bed after each eruption of the torrent. “One may see that there is no need of any building to confine these secondary torrents, and that the inhabitants of each village, with their shovels, their pick-axes, and some wheel-barrows, may secure the territory from the ravages. It is much to be desired, that being enlightened in regard to their true interest, they should lose at last that indifference which keeps them alike from preventing their ruin, and from repairing it. “Tt may be observed that it is not necessary that the new bed be dug throughout all its length in asingle campaign. It suffices to begin at the foot of the mountain, and to end off the open part in any year, by a more gentle declivity than that of the deposit of the ravine, to give an outlet to the waters. Thus the inhabitants would do wrong to excuse themselves by an alleged impossibility of doing all the work at one time. Further, neighbouring communities could mutually help one another. “ The advantages which the communes would derive from this work are considerable ; for, not only would they not have to fear new invasions of the torrent, but the sides of the torrent, not being now exposed to the waters, wight be usefully cultivated, by watering them with waters of the torrent which might be derived from the upper portion of it.” The scheme proposed resolves itself (he says) simply into digging for the torrent a straight canal through the centre of the deposit, and maintaining this canal by constant clearings. According to M. Ladoucette, whatever may be the precautions proposed by the author for strengthening the hills by means of plantations and cuttings like to continuous dykes, they will never present sufficient resistance to erosion ; still less will they hold out against the undermining effects of the flood. It is mentioned by M. Surell, that the clearing out of torrents is always a difficult operation, on account of the great size of the stones, and the hardness of the mud in which they are imbedded ; and that this work, which demands great waste of muscle, and entails great expense, produces no durable result. The smallest flood suffices to overturn all, and to throw the bed of deposit into its previous disorder. Something similar or analogous to the proposal of M. Cormant was carried into execution by M. de Ladoucette, who caused a trench to be cut ina straight line from the gorge of the Durance. He employed in this work the prisoners confined in the central house of Embrun, to the number of five hundred, and the work, prosecuted with energy, was completed in a month ; but in the course of the next month there came a flood, and all was destroyed. This scheme attributes all the ravages of torrents to the irregularity of their beds ; and proposes, as a simple and sufficient remedy, to give to them a straight bed. Surell alleges that the scheme confounds cause and effect ; and that torrents do not spread themselves hither and thither because they have not a straight bed ; but they have not a straight bed because, con- tinually depositing matter, they are forced to spread themselves hither and thither. 78 LITERATURE ON TORRENTS, M. Cormant might justly claim to be allowed to say, in defence of his suggestion, that had the artificial bed been of a magnitude to contain the whole flood, as was evidently requisite, the success might have been complete, In 1856 appeared, as has been already mentioned, the pamphlet of M, Rozet, entitled Moyens de forcer les Torrents des Montagues de rendre une partie du sol quils ravagent, to which reference has already been made. “He proposes,” say Marsh, “to commence with the amphitheatres in which mountain torrents so often rise, by covering their slopes and filling their beds with loose blocks of rock, and by constructing at their outlets, and at other narrow points in the channels of the torrents, permeable barriers of the same material promiscuously heaped up, much according to the method employed by the ancient Romans in their northern provinces for a similar purpose. By this means, he supposes, the rapidity of the current would be checked, and the quantity of transported pebbles and gravel—which, by increasing the mechanical force of the water, greatly aggravate the damage by floods—much diminished. When the stream has reached that part of its course where it is bordered by soil capable of cultivation, and worth the expense of protection, he proposes to place along one or both banks, according to circumstances, a line of cubical blocks of stone or pillars of masonry three or four feet high and wide, and at the distance of about eleven yards from each other. The space between the two lines, or between a line and the opposite high bank, would, of course, be determined by observation of the width of the /swift-water current at high floods. As an auxilliary measure, small ditches and banks, or low walls of pebbles, should be con- structed from the line of blocks across the grounds to be protected, nearly at right angles to the current, but slightly inclining downwards, and at convenient distances from each other. Rozet thinks the proper interval would be 300 yards, and it is evident that, if he is right in his main principle, hedges, rows of trees, or even common fences, would in many cases answer as good a purpose as banks and trenches or low walls. The blocks or pillars of stone would, he contends, check the lateral currents so as to compel them to let fall all their pebbles and gravel in the main channel—where they would be rolled along until ground down to sand or silt—and the transverse obstructions would detain the water upon the soil long enough to secure the deposit of its fertilizing slime. Numerous facts are cited in support of the author’s views, and I imagine there are few residents of rural districts whose own observation will not furnish testimony confirmatory of their soundness.” He says,—“ The plan of Rozet is recommended by its simplicity and cheapness as well as its facility and rapidity of execution, and is looked upon with favour by many persons very competent to judge in such matters. It is, however, by no means capable. of universal application, though it would often doubtless prove highly useful in connection with the measures now employed in south-eastern France.” And he adds, in a foot-note,—“ The effect of trees and other detached obstructions in checking the flow of water is particularly noticed by Palissy in his essay on Waters and Fountains, p. 173, edition of 1844. ‘There be? says he, ‘in divers parts of France, and specially at Nantes, wooden bridges where, to break the force of the waters and of the floating ice, which might endamage the piers of the said bridges, they have driven upright timbers into the bed of the rivers above the said piers, without the which they HTUDES BY SCIPION GRAS, 79 should abide but little. And in like wise, the trees which be planted along the mountains do much deaden the violence of the waters that flow from them.’ Lombardini attaches great importance to the planting of rows of trees transversely to the current on grounds subject to overflow.—Hsame degli Studi sul Tevere, § 53, and Appendice, §§ 33, 34.” In 1857 there appeared, in the Annales des Ponts et Chaussées and in the Annales des Mines, Etudes sur les Torrents des Hautes Alpes, by M. Scipion Gras, ingénieur des mines. Of this work the following analysis is given by M. Cézanne, in his supplement to the work of Surell :—‘‘ After having defined torrents the author divides their course into four parts—bassin de réception, canal de réception, lit de déjection, and lit découlement. M. Scipion Gras distinguishes amongst torrents at the bed of deposit four classes, according to the character of the basins drained by them. The study of the laws in accordance with which solid bodies are swept away by floods leads him to the conclusion that there are two distinct modes of operation —transport en masse and transport partiel—the former effected by floods of great body and strength, the second by floods of a medium character. These different operations produce contrary effects upon the bed of deposit ; the great floods, as they exhaust themselves, deposit over this a layer of clay and gravel, over or through which the waters spread themselves in thin sheets ; the lesser floods, on the contrary, dig down into the bed of deposit and plough in it a channel for themselves, after having conveyed thither the more comminuted materials referred to.” Upon which M. Cézanne remarks that M. Gras does not occupy himself much with the basin drained by the torrent, the special subject of study by him being torrents the basins of which are not susceptible of being planted ; and impressed with the evils resulting from the dejection of detritus, he seeks to modify the natural advance of the bed of gravel, and discusses the two methods generally employed to effect this, characterized respectively by the employment of dykes and of barrages, or embankments and barriers. He expresses himself very decidedly in favour of barrages, and he thus sums up his opinion on the point :—“ In short, the first proceeding (l’endiguement ), ag a means of suppressing a bed of deposit, is often impracticable, or at least the success of it is dubious ; when it does succeed, it only carries the mischief elsewhere. It is, then, one which is very defective, and which ought to be abandoned. “ There remains the second course of proceedure ; we have demonstrated its practicability, as applicability to all torrents, and its freedom from the drawbacks attaching to the first. And here begins the most important part of our task.” This quotation (says Cézanne) is characteristic of the method of procedure of M. Gras, which is pre-eminently systematic; he observes natural pheno- nema with great accuracy and precision ; he then proceeds to distinguish, to classify, and finally to bring all his energy to bear upun a single and exclusive system. “But,” says M. Cézanne, “ the consideration of nature inspires one with a dislike and opposition to all systematic formulas. It may be well to run down embankments, and extol barriers ; but it is not less the case that there are circumstances in which the practical man will see at a glance that there embankments are better adapted to meet the case than are barriers, And it is necessary, in a study of this kind, to avoid all 80 LITERATURE ON TORRENTS, special pleading in support of the absolute superiority of one system or of another, and to confine remarks to showing clearly in what circumstances either of them should be preferred. “M. Gras being so decidedly in favour of the exclusive use of barrages, or barriers, in reference to the two different categories of floods established by him, recommends, according as it may be desired to effect a complete or a partial retention of gravel, the construction of submergible barriers in the latter case, and insubmergible barriers in the former. “The latter, insubmergible—so designated, although actually overflowed by the torrent, and expected and intended to be so at times, and it may be frequently—belong to a class of embankments which have been long in use. Erected in some favourable position in the gorges, they are designed to effect a deposit of gravel directed up the river. If the reservoir designed for this deposit be very considerable, if the transport be slow, it may tell effectively for some distance below for several years. “ Submergible barrages constitute, strictly speaking, the system which M. Gras claims the credit of originating. This system is based on a very delicate analysis of the effect of floods, which shows that high waters only acquire their full force in a narrow channel in which they are confined. If they be allowed or compelled to spread themselves out, their force is diminished, and the larger materials which were being borne along by them are deposited. To compel them to do this—to spread themselves out—it is only necessary to raise, on a widening of the bed, a horizontal sill, which cannot be washed away, worn down, or furrowed ; the waters, then, not being able to concentrate themselves in any place at a lower depth than that of the whole sill, spread themselves in a sheet over the sill, and a deposit up the river follows as a consequence. “ After a great flood, such as may be of occcasional but comparatively rare occurrence, floods of lesser magnitude, which are much more frequent, go over this deposit anew, and do on a lesser scale what the greater flood has done on a greater, excepting that such large blocks as could only be carried along by a great flood will remain in the places above the barrier in which they had been left. And the effect of the whole will be, that great floods will be less disastrous, the work done by them being effected by a great number of floods, the consequences of which are innocuous. “Tt is not necessary that these barrages should be of great height, ‘nor, consequently, of great solidity ; it isenough that their upper surface sustain the friction of the pebbles carried down by the flood, and that their base can sustain the slight water-fall which they occasion. “From this it may be seen,” says M. Cézanne, “ that the system of oper- ations proposed by M. Scipion Gras is the very opposite of the course formerly followed, in so far as formerly, when a dam or barrier was to be erected, a narrow depth in the bed of the current was selected, that the structure being short there might be given to it, at little expense, the thick- ness necessary to enable it to resist the violent action of the water. He recommends to select expansions in the bed of the current, and even proposes to erect, on the cones of dejection, works of the same kind, which he calls barrages radiers. To secure the plain of Bourg d’Oisans, in the basin of the former lake Saint Laurent, against ravages by the Romanche and the Vénéon, which debouche each by a different gorge, he proposes the erection of such barriers, spread out horizontally, the length of which should be not less than 763 métres, or 2500 feet, upon which he supposes that the TUDES BY SCIPION GRAS. 81 two torrents, uniting their floods, will pour out the mass of water ina regular sheet, 32 centimétres, or 12 inches, in fall.” Of this locality it is mentioned elsewhere by M. Cézanne, that in 1157, after a storm of rain, two torrents of the Oisans, which look directly across from one bank to the other of the Romanche, the Vandaine and the Infernay, raised a barrier across the principal valley ; a lake formed itself immediately behind this dam, which was known under the name of the Lake Saint Laurant, because the storm had burst on the day of St Laurant. This lake stood for sixty-eight years, but in the night between the 14th and 15th September 1219 the barrier gave way, the waters laid waste the lower parts of the valley, and two towns, Vozille and Grenoble, were almost entirely destroyed. Since the thirteenth century onwards there has often been a threatening of the formation again of this barrier, but in despite of this there has sprung up, in the dried basin of the Lake Laurant, the Bourg d’Oisans, which M. Gras proposed thus to protect. M. Cézanne states in detail objections to which the measure was deemed by him to be open; and referring to two practical applications which had been made of the system proposed by M. Gras—one on the Roise, near Grenoble, the other on the Riou-Bourdoux, in the Lower Alps—he cites observations made by Professor Culmann, who visited the former some three years after the publication of the memozre, and reported of it thus :—“ At the time of our visit (October 1860), we found that a strong débdcle had just passed over a barrage, and that a great mass of rubbish had been stopped behind the upper barrier. The little wooden bridge a little above it had evidently had too weak a channel, and it was carried away, and the barrier itself could not resist more. . . . “Tt is clear that the work had maintained its resistance until the deposit above it had attained the top of its slope, and that so soon as blocks of even small size began to roll over the inclined plane the links of the binding chains, formed of iron bars ‘02 métre, or four-fifths of an inch, in thickness, yielded to the shock and opened.” “ Beyond this,” says M. Cézanne, “ M. Culmann criticises the mode of constructing rather than the theories of these barriers, but he does not appear to attribute to them other effect than to determine a deposit in the same way as does every other kind of barrier.” M. Cézanne visited La Roise in 1869, and he says,—“ In point of fact, the bed of La Roise presents to a visitor the ordinary appearance of the bed of a torrent. The repaired barriers are surmounted by deposits, and the old state of things appears to be exactly reproduced at a higher level. “ According to M. Marechal, Ingénieur des Ponts et Chaussées, the experi- ment tried on the Riou-Bourdoux has not been more successful ; the barrier has perished through defective or vicious construction.” M. Cézanne states, in concluding, that notwithstanding failures, which have followed a practical application of it, which have been made, in some of which the failure was attributable to unsatisfactory workmanship, engineers who have to do with torrents, but who have not had much personal experience in connection with torrential phenomena, will read with much profit the memoir by M. Gras; they will find a great many facts carefully noted, and will learn how to make observations themselves. And others who have written upon the subject go, I may mention, far beyond this in their commendations of the measure proposed by M. Gras. In regard to triage, selection or successive deposit of materials of different H 82 LITERATURE ON TORRENTS. bulk or gravity, a subject underlying the proposal of M. Gras, M. Cézanne writes,—“ The triage of the matters borne along is very strongly marked in torrents which tend to extinction, or only, if the case be so, to take a régime of greater constancy. It happens even that the lesser stones, &c., being all borne along, there remain only the larger ; the bed is then furnished with a self-created rockery, which energetically resists erosion, and as a necessary consequence the torrent cannot deepen the channel in which it flows. It is then necessary to give some assistance to the torrent, and the larger blocks are removed and ranged along the bank. The water re-collected between these rude embankments digs away anew. This system is much used in Switzerland. The course to be followed is this : replant with woods these parts of the basin in which this can be done ; and when the torrent shows a tendency to cut a bed in the dejection, facilitate the process by removing the self-formed rockwork of blocks denuded by the triage.” In 1865 was published IMemoire sur les barrages de retenue des graviers dans les gorges des Torrents, by M. Philippi Breton, Ingenteur des ponts et Chaussées. Of this M. Cézanne says,— This treatise may be justly charac- terized a treatise on torrential geometry; the author demonstrates in it, with beautiful clearness and distinctness, the principal theories which relate to the transport of gravel,—to the profile or outline of the bed of deposit,— to the different kinds of cones thus formed, the troncature or section of which, and the reproduction of which, are explained by beautiful sketches taken from nature.” Of the design of the work, M. Breton writes,—“ Different questions connected with the establishment of barrages, or barriers, for the retention of gravel, have been raised and discussed. But, notwithstanding all that has been done, it appears to me that ideas in regard to what results are to be expected from these barrages are still vague, varied, and undetermined; there is still a great want of decision in regard to selection of location, to the number of barrages to be employed, to the best or most suitable means of constructing them, and to the duration of their efficiency. After having reflected long on these subjects, I have come to be of opinion that, to preserve a plain from invasion by a torrent which debouches on it, it is necessary to establish, in the first place, a single barrage, situated at the outlet of the gorge, or very near to this ; then a second barrage at some métres [or yards], and not more, above the first, when that one shall cease to be efficacious ; then a third at some métres above the second, when this in its turn shall have completed the service it can render; and so on. Such is the subject of this memoir.” “From this it appears,” says M. Cézanne, “ that the proposal of M. Breton is the very opposite of that of M. Scipion Gras, submitted eight years AO 5 he speaks not of barriers but slightly raised above the level of the bed, or of silts stretching across expansions in that bed, but of solid massive walls, carried up as high as possible by successive stages into the throat of a gorge, and constructed, not of blocks bound to one another by chains, but of hydraulic masonry of the strongest that can be obtained. “ Barrages in which wood is employed to meet the want of cohesion in gravel, last (says he) but for a short time,—for the wood, buried half of its bulk in the gravel, often dry and often wet, will quickly rot, as quickly as do the Cabrettes, and more quickly than do the coffers known under the name of arks (arches) in the mountains of Dauphiny and Provence. Barrages MEMOIRE BY PHILIPPI BRETON. 83 constructed entirely of rockwork, and those constructed of dry stones, never cost much less, and they sometimes cost more, than those built with Roman cement, and these have a great advantage over the others in their greater cohesion. Ag soon as a breach occurs at any height in a barrage of rocks or dry stones, the violent current, passing through the breach, begins at once to enlarge it, and it soon effects a great destruction. In the hydraulic masonry any opening can only enlarge itself slowly, and the flood will have exhausted itself before the destruction has become serious. “‘Tn saying what I have done I am only extending to barriers retaining gravel the practical rule adopted in the department of Isére for longitudinal dykes. M. Picol, and the engineers under his orders, have often remarked that a dry-stone dyke is rent from the bottom to the top when a small breach has been made in the foundation. Wishing to make these observa- tions complete by comparison, they made the experiment of building with stones set in good hydraulic mortar. The experiment was not long in revealing—first, that the dykes so constructed did not cost much more than did those built of dry stones, as they could build with smaller material, and they did not require to give the same thickness to the wall; and then, what is of primary importance, that a wall built with good mortar can sustain a considerable destruction at its base without being instantly rent to the top, for the part above sustains itself in the condition of an arch or vault ; and thus time is afforded for assistance.” After having discussed in detail the different questions which are connected with barrages, M. Breton thus meets an objection which is often brought up:—‘“I have frequently heard educated and intelligent men object against the system of retaining gravel by barrages the danger of a rupture in the works. When these works shall have amassed a great mass of gravel behind them, if a rupture should occur, that entire mass, so retained above its level, would, it is said, suddenly begin to move, and would produce a frightful catastrophe below. And as a proof in support of this fear they adduce the effects attributed to the sudden emptying of the Lake St Laurent, which, escaping from the plain of the Oisans, laid waste the valleys of the Romanche, and of the Drac, as far as to Grenoble. They might adduce, in like manner, the lamentable disasters produced in a single night by the rupture of the reservoir at Sheffield! But they forget that in these two cases, ag in all others which may be cited in which the rupture of a reservoir has caused a sudden catastrophe at a lower level, the state- ment refers}to a reservoir of water, and not to a reservoir of sand, and earth, and gravel. “Tt is thus that I have no dread of this objection, if the work be judged of only by builders accustomed to see the movements of water, and of sand and gravel, and know the difference between them; never will an engineer bring himself to believe that gravel will flow as does water.” Numerous cases illustrative of the effects of the rupture of a barrage are then given. But M. Breton, while writing thus, is not unmindful of the importance of the borsement or gazonnement of the basin drained by the torrent. He admits distinctly that it is vegetation which has the power to extinguish torrents ; he only proposes barrages as a temporary expedient against torrents which cannot be prevented, as are sometimes those connec- ted with glaciers, or as temporary appliances where, through the strength of prejudice or legal difficulties, the forest treatment must be for a consider- able time postponed. : 84 LITERATURE ON TORRENTS. In the same year, 1865, there was published in Lausanne, a Rapport au Conseil Fédéral sur les Torrents des Alpes Suisses, inspectés en 1858, 1859, 1860, and 1863, par M. le Professeur Culmann. Of this work M. Cézanne writes,—‘ Switzerland is a land privileged indeed ; the philosopher, the artist, the humble foot-soldier—in a word, every one, whatever may be the tendency of his mind, finds there numerous subjects of study. By hundreds of thousands, tourists, from both worlds, annually visit this classic land of noble landscapes, of natural science, and of freedom.” He mentions in a foot note, that he was informed, by the monks of the great Saint Bernard, that they lodge upon an average 40,000 visitors annually, and sometimes 800 in a single day at the height of the season. And he goes on to say,— “ Looked at from the point of view of our study, Switzerland is seen to be a protuberance, like a boss on a shield, which rises above the lofty plateaux of Europe; it isa reservoir, whence water is distributed; it is also a laboratory, whence issue many thousand torrents—working away, in combination with the glaciers, to level down the rough and rugged back of our planet. All of these waters, flowing from the eternal snows, precipitate themselves in cascades to the depths of the valleys below ; they keep on, ever sowing anew with their alluvial deposits the basins of a hundred score of lakes ; thence, partially clarified, they escape towards the four points of the compass to throw themselves into four seas, after having watered Germany by the Danube and the Rhine, France by the Rhine, and Italy by the Po and the Adige. “The engineers of this country, brought up within the sound of the torrents, and accustomed from infancy to the thousand caprices of the moun- tain streams, quickly acquire a special experience in thismatter. They are little given to generalizations, to systematic theories, to geometrical definitions; they give themselves more to the study of particulars, and seek out for each cage a special solution adapted to the local circumstances. And such is the character of the work of M. Culmann. “Tn 1856, the rainfall which devastated France did not spare Switzerland ; the Federal Council bestirred itself and commissioned M. Culmann, one of the most distinguished students of hydraulics, to go through the whole of the cantons, and to report, in regard to each torrent, on the evil and the remedy. And at the same time, to meet the public demand, which attributed justly to the destruction of forests the ravages of the torrents, a commission was organized and appointed to report at the same time in regard to the forests. The two reports have been published in German and in French. They agree on the conservation effected by forests. That of M. Culmann relates more especially to those water-courses connected with which the mechanical appliance of the engineer is required to come to the aid of reboisement. “The report of M. Culmann passes in review many hundreds of torrents ; it is a repertory of isolated facts, well observed, calmly stated, with simple demonstrative sketches.” . . . With regard to boisement and gazonnement, he says,—“ In Switzerland, as elsewhere, the evils produced by torrents is not a necessary evil; it takes birth often from the waste and recklessness of the inhabitants. The principal remedy, and the only one which is decisive and definite, is the boisement or gazonnement, which stifles the evil at its source, principits obsta. The cantons which have given attention to their forests have been least attacked ; those which have devastated them—in particular the Italian cantons—are threatened, as are the HighAlps of France, with complete RAPPORT OF M. OULMANN. 85 ruin.” And he gives a great many examples of cases in which, in conse- quence of the grubbing up of a wooded place, a torrent, which till then had been inoffensive, became all at once dangerous. M. Culmann attaches greater importance to the initiative bemg taken by the people, than to interventions by the Government ; and he cites facts in support of his opinion. But he attaches, I may say, primary importance to securing connected action by all interested ; of the advantages of which, and the disadvantages arising out of the want of it, he gives facts in illustration. Proceeding to the consideration of mechanical works of engineering, he recommends—(1) The clearing of the water-courses of all large blocks resting there, in which he is supported by M. Cézanne ; (2) The erection, when and where it may be expedient, of barrages and dykes or embankments. “Tn regard to such works, the theory of M. Culmann,” says M. Cézanne, “may be stated thus :—Barrages are but a temporary expedient to be employed while awaiting reboisement ; it is necessary to construct them in a series, commencing from below ; when the first barrier is filled to the level with gravel, then should be constructed a second behind it, and so on continuously.” Barrages are the preferable structures to erect against torrents, dykes or embankments against rivers. With these, as with barrages, it is necessary to proceed from below upwards. Barrages constructed of faciues or of wood, &c., when but a temporary effect is to be produced, are often preferable to those of stones or of masonry, because they accommodate themselves to movements in the bed. Structures of facines form a moveable enclosure, on which vegetation easily establishes itself ; barrages, constructed with hurdles, are very useful in ravines, and even on sinking slopes; but in general stone-works are preferable to those constructed of wood; these, however, are very serviceable in cantons in which the population employ them. ‘All the barrages in torrents con- structed hitherto in Switzerland,” says he, “‘have proved beneficial ; all the people who have made use of them have showed themselves satisfied with them.” Epis, or stakes, avail nothing against torrents, or against mountain rivers ; they are available only against peaceful rivers, bearing along but little solid matter suspended in their waters, and this composed only of sand and small gravel, and not of blocks, which are able to attack the bank and change the direction of the liquid stream. “The stockade of these,” M. Culmann says, “ should form a continuous line ; for if some do not reach to this, and others go beyond it, the current, thrown from one bank to the other, may do greater damage than if there had been no works of enclosure. The epis, or stakes, should be sufficiently close to the bank to prevent any loop or expansion of water being formed between them ; and the’ less the banks the closer should they be. In mountain banks the space is so limited that continuous dykes are less costly. “Tn Bavaria, for example, the lower Danube is too small to allow of the system of stockade being applied ; they are under the necessity of adding a more or less extended wing to the back of each spike—that is to say, to construct immediately a portion of the future bank. They have also aban- doned the system of spikes along the Rhine, where they were greatly attached to it, and where they now construct continuous embankments of facines. Stakes can no longer be employed along the Lech ; and since the alteration of the course of the Linth, they have become satisfied that parallel 86 LITERATURE ON TORRENTS, dykes are much better suited for the enclosure of this small water-course. And on all the lower channel of the Linth, they have little by little replaced with these the stakes wherever these were not absolutely necessary.” M. Culmann then reports in detail in regard to the location and construction of bridges; and on the phenomena and effects of glaciers, torrents, avalanches, and landslips. The former subject is of local importance ; and the information communi- cated may be utilized, to some extent, by any employed in making surveys for roads and bridges ; but in every case local circumstances have such an effect in determining operations that it is deemed unnecessary to cite the views advanced. With regard to glaciers, torrents, avalanches, and land- slips, the case may seem to be similar. But avalanches, at least, are not confined to Alpine regions; and though woods may prevent the formation of a landslip, they cannot arrest its progress when once in motion. There is not a little in the graphic details of engineering operations given by M. Culmann in this chapter of his work which commands attention and illustrates the importance of the work. “Torrents issuing from glaciers,” says M. Cézanne, “are numerous in Switzerland ; they are subject to formidable débdcles, or outbursts of water, when the glacier in its movements of going and coming, after having dammed up some secondary valley, gives free passage all at once to its waters. To prevent such evils is for the engineer a formidable undertaking, and a difficult problem. How contend against a glacier? What physical force can he bring against the mass which is being unceasingly renewed by the ever recurring winters, and which, making use of the hardest rocks, trans- porting blocks of stupendous size by a movement almost imperceptible, would annihilate the most irresistible work of man? Here are two cases reported in which a simple idea sufficed to vanquish the inert Colossus : “The glacier d’Aletsh, an affluent of the Rhine (Valais), dammed up a small lateral valley, situated behind the Eggishchorn, and created thus the lake of Merjelen. ‘ This lake,’ says M. Agassiz, in his tudes sur les Glaciers, ‘was formerly more extensive than it is now; and when it happened that the melting of the snow and ice became excessive, it would often happen that the whole of this body of water would with violence eat away an outlet under the glacier, and occasion the greatest destructive ravages in the bottom of the valley. To obviate this they dug, in the direction of the glacier of Viesch, an artificial channel to this lake, which could no longer rise above the level of its orifice. The ice did not rest immediately on the water ; there was, on the contrary, between the bottom of the glacier and the surface of the water a space of some centimetres, perhaps an inch or two, occasioned by the temperature of the lake being always during summer higher than that of the glacier. By means of this space, enormous blocks of ice often detach themselves and float on the surface of the lake, imitating exactly the floating icebergs of northern regions.’ “But the most characteristic example is that furnished by the glacier of Gittroz—the assault made against which is somewhat dramatic, and exceedingly interesting : “At the bottom of the valley of Bagnes, one of the branches of the Drause, at sixteen kilométres, or about twelve miles from Chables, there rises vertically a high wall of rocks, surmounted by the glacier of Giétroz. The moving mass protrudes itself, projects beyond the support, and falls at the a GUIDE JOANNE. 87 foot of the precipice ; the broken fragments congeal anew and form a cone- shaped glacier, which pushes before it its moraine. What ensues must be» given in the narrative of Guide Joanne:—‘In those years in which avalanches are very frequent the heat of summer does not suffice to melt a quantity of ice equal to what the mountains cast down. The enormous block which then forms a bridge on the Drause becomes always larger and larger, and as the arch of this bridge, dug in summer by the torrent, closes up in winter, it happened in 1597, and in our own times, in 1818, that the early months of spring sufficed not for the Drause to open for itself a passage, and a lake was formed behind the ice. “ «When this became known (wrote M. Simond, some months after the event), alarm spread at once, not only throughout the whole valley but in Le Valais, and on so far as Italy. Travellers feared to take the route of the Simplon ; it was felt that when this dyke should come to break up there would be there a sudden débacle which would sweep over the country to a great distance. The preceding winter had been severe; the ice had even then cast a dam across the valley, but without stopping the water, which had eaten out a passage for itself; but a second severe winter had produced such a fall of ice that the obstacle had become insurmountable and impervious. “¢The Government sent an engineer (M. Venetz) ; he found that the dyke was 110 toises (nearly 700 feet) in length from the one mountain to the other, 66 toises (or about 400 feet) in height, and 500 (or 3000 feet) in thickness at its base. The lake was 1200 toises (or upwards of 7000 feet) in length, and had already risen to half the height of the dyke, that is to say, was from 30 to 40 toises (from 180 to 240 feet) indepth. The engineer determined to cut a gallery or tunnel through the thickness of the ice, beginning 54 feet above the actual level of the lake, to give time to complete the work before that height should be reached by the accumulating waters, which were rising at the rate of from 1 to 5 feet per day, according to the temperature ; and he began the work on the 11th of May at both ends of the tunnel. Fifty men in relays, relieving one another alternately, wrought there night and day at the peril of their lives,—one and another of the avalanches which were falling every moment threatening to bury them alive in the tunnel; many were wounded by lumps of ice, or had their feet frozen, and the ice was so hard that it frequently broke the pick-axes used. In despite of all these difficulties the work advanced rapidly. On the 27th of May a great piece of the dyke broke off from the bottom with a fearful crash ; it was believed that the whole was about to break up, or to rise in a mass, and the workmen fled; but soon they courageously resumed their work. Similar accidents occurred repeatedly ; some of the floating masses, calculating from the distance at which they stood above water, must have had a thickness of 70 feet submerged. On the 4th June the tunnel, 608 feet long, was cut from end to end; but as it had an elevation of 20 feet or more in the centre it was necessary to level it. The weather had been cold, and the lake had not yet risen to the level of the mouth of the tunnel, so they continued to lower this till the 13th, the day on which the flow commenced, at ten o'clock at night. The lake still rose for some hours; but next day at five o’clock in the afternoon it had sunk 1 foot; on the morning of the 15th, 10 feet ; on the morning of the 16th, 30 feet ; at two o’clock that day the length of the lake had shrunk 325 toises (nearly 2000 feet), for the tunnel, being continually eaten away, lowered itself as quickly 88 LITERATURE ON TORRENTS. as the lake. The Drause flowed, filled from bank to bank, but without overflowing, and a few days more would have sufficed to empty the immense reservoir, “¢ But detonations in the interior of the dyke announced that glacions, blocks and pillars of ice, were detaching themselves from the mass, through their low specific gravity, and were thus diminishing the thickness of the dyke on the side towards the lake, while the current out of the tunnel was eating away this dyke on the outer side, and was threatening a sudden rupture ; the danger increasing, the engineer despatched from time to time expresses to warn the inhabitants to keep themselves on the out-look. The water began to make way under the ice, sweeping along the stones and earth at its base under the tunnel; the crisis appeared inevitable and close at hand. At half-past four o’clock in the afternoon a tremendous crash announced the rupture of the ice-work ; the water of the lake shot along with fury indescribable ; it formed a torrent 100 feet in height, which traversed the first 6 leagues, or 18 miles, in forty minutes, although kept back in many places by narrow gorges through which it had to pass, carrying off in its course 130 chalets or cottages, a whole forest, and an immense quantity of earth and of stones. Debouching over against Chables, the chief place of the valley, the water was seen pushing before it a moving mountain of all kinds of debris of 300 feet in height, from which was rising a thick black cloud like the smoke of a conflagration. An English traveller, Mr P., of Lausanne, accompanied by a young artist, and a guide, was returning from seeing the works, and going towards Chables ; happen- ing by chance to turn round, he saw advancing with fearful rapidity the moving column, the distant roar of which he had not heard through the noise made by the Drause. He hastily warned his two companions and three other travellers who had joined them ; all leapt from their mules, scrambled up the mountain, and got safely beyond the sweep of the deluge, which filled in an instant the whole gorge beneath them. But Mr P. was nowhere to be seen; for some hours they believed him to be lost; but then they learned that his mule, shying at an overturned tree which she saw on the road, wheeling round, saw all at once an object far more dreadful close upon her, and, darting off towards the mountain, had carried him far away from the scene of danger. “From Chables the débacle arrived at Martigny—4 leagues, or 12 miles, distant—in 50 minutes, carrying off, as it advanced, 35 houses, 8 mills, 95 barns, but only 9 people, and no cattle, the inhabitants having all been warned to be on guard. The village of Bovernier was saved by a jutting rock turning off the flow of the torrent ; and the people saw it pass like a shot by the side of the village without touching it, although much higher than their heads. The rocks and stones were dropped before it arrived at Martigny, blasting with sterility extensive meadows and fertile fields. “There it divided, but 800 of the houses cf this town were carried away, many others were damaged, and the streets were strewn with trees and earthen debris ; 34 people only appear to have lost their lives there, the inhabitants having betaken themselves to the mountains. “ «Below Martigny the débacle, finding a great plain, spread itself out and deposited a great deal of mud and wood, and that to such an extent as to render healthful, as was hoped, a great marsh there. The Rhone received it little by little, and at different parts of its course, without overflowing ; it reached the lake of Geneva at eleven o’clock at night, and was lost in RAPPORT OF M. CULMANN. 89 the great extent of that lake,—having traversed a course of 18 leagues, or upwards of 50 miles, through Switzerland, in six hours and a-half, by a movement gradually retarded. “¢ All the bridges having been carried away, the inhabitants on the two sides of the Drause could have no communication for some days, or inform one another of their respective losses, but by throwing across the river notes attached to stones; and the putrifying slime threatened them with an epidemic. It is somewhat remarkable that an old man of ninety-two saved himself by getting on a hillock supposed to have been formed by a débacle in ancient times; the new one followed him to the very summit, where he maintained his footing by the aid of a tree which was not carried away. “<¢M, Escher estimated at exght hundred millions of cubic feet the mass of water which had accumulated at the time it began to flow out by the tunnel. This mass had been reduced to jive hundred and thirty millions in the course of the three days following, and the level of the lake was lowered by 45 feet. Ifthe tunnel had not been made the lake would have risen 50 feet higher, and the mass of water would have attained a measure- ment of seventeen hundred and fifty millions of cubic feet when it began to flow over the dyke, instead of the jive hundred and thirty millions to which it had been reduced when it began to pass across the tunnel, and would have spread its ravages over the whole of the lower Valais.’” M. Culmann goes on to say,— When, in the course of the winter of 1821-22, the dyke of ice threatened to form again, and had already covered about 400 métres, or upwards of 1300 feet, of the bed of the Drause, M. Venetz undertook to destroy this mass of ice, the face of which measured 22,300 square métres. “ He succeeded completely in doing this by the help of wooden aqueducts, leading on to the glacier streamlets of water from the mountain Alia, heated in some measure by passing over the rock ; by these means were made great gashes, which detached blocks of 800 and 1000 cubic feet in measurement, In falling down, these broke in pieces, which were carried away by the Drause. “ After having destroyed the cone of the glacier, from 1822 to 1824, M, Venetz undertook precautionary works to prevent the blocks of ice precipi- tating themselves anew to the depth of the valley. He constructed simple barriers across the valley over against the glacier. The summits of these are perfectly straight and horizontal ; they produce thus so great a lateral extension of the surface of the water, that the ice-work cannot make a vault across it. The blocks of ice fall, then, always into the waters, remain con- stantly in contact with this, and melt away by degrees. Thus the stream can never be covered up, and the blocks of ice cannot precipitate themselves further. From the time that the cone overhangs, by 2 or 3 métres, 7 or 10 feet, the stream which has dug away its base, the portion in front detaches itself, and is borne away. These sometimes fall beyond the stream, and form a small glacier at the side of the moraine, on the left bank. And these masses maintain their ground sometimes for a pretty long time, but they can never cover up completely the stream. “From that time onward—that is to say, from 1826—these barrages have sufficed to prevent the ice-work from covering up the Drause, and thus damming up the valley. “Tn acknowledging the great merit of these works, we may express the wish that the engineers of this canton could be enabled always to avail them- selves of the means necessary to maintain such useful structures, so as to I 90 LITERATURE ON TORRENTS. erect similar ones in other valleys—amongst others, in those of Saas and of the Massa.” : These extracts, from the report of M. Culmann, will suffice to show how interesting this report is for engineers who have to do with torrents. As yet comparatively little had been done to carry out reboisement and gazonnement in France. M. Culmann visited the High Alps, having had his attention directed to several of the works published in regard to the torrents of that region, and the remedies proposed by Fabre and Surell, and advo- cated by others. And he thus reports on what he saw,—“ Our expectations were disappointed. One torrent alone had been subdued, and that not one of the most formidable of them ; it was not in the basin of the Durance, so cut up with ravines, but in the comparatively peaceful one of the Isére. In what is, properly speaking, the domain of the torrents, they have made an experiment in rebotsement by a plantation of pines, of some thirty or forty acres in extent, in the bassin de réception of the formidable torrent of Chorges. “These, and some few others, on the smaller mountain banks, are the only practical results which all the studies of the engineers have produced since the close of the last century. . . In no country is the Administra- tion des Ponts et Chaussées so centralized and so well organized as in France ; but in whatever direction we look we are saddened by the painful impression that a state of things far superior, previously existing, has been brought to nought. It may be asked, perhaps— Why then devote so much time to it ? And what has the condition of a foreign land to do with Switzerland 2 “We were convinced that our general description of torrents could not be closed more advantageously than in showing how a country has, little by little, been brought to a state of ruins, when its population did nothing to maintain it—did nothing but consume the products of the soil, and sought not by any natural or artificial process to repair their losses, or to preserve its power of production. “Let this state of things be considered by us while it is not yet too late ; and let no one reply,— We shall never sink so low as that; if the country be more and more neglected—if its condition be allowed to go on becoming worse for an indefinite length of time—it will end, as will also its population, in differing so little from what we have just described that their conditions will be identical.” M. Cézanne remarks on this,—‘“It is humiliating to meet with such a testi- mony in an official document, published in two languages, by a foreign Govern- ment, and spread over the whole of Europe. It is a canton of our own France which has thus been pointed out to all as an example of the evils to which inertness of administration may lead. It is in vain that eloquent appeals have been made since the commencement of the century ; nothing has been done, and the ruins of the valley of the Béouse, in Devoluy, described by Surell, are still there to supply a subject for heart-rending pictures.” If these severe observations be now no longer true—if anything has been done—thanks to the law of 28th July 1860 on the reboisement of the moun- tains, and above all to that of the 8th June 1864 on gazonnement, The last, I may state, was passed in the year following the completion of M. Culmann’s tours of inspection; and translations of the text of both laws, with documents connected with them, will be given in a subsequent Part of this compilation. I found in a paper which appeared in Revue des Faux et Foréts, for REVUE DES EAUX ET FORETS, 91 April 1866, the following striking illustration of the effect of woods on torrents :—“ The State possesses, in the department of Vancluse (says the forest conservator, Labuissi¢re), a forest of more than 3000 hectares, situated on the portion of the mountain Luberon nearest to the valley of the Durance. This region is very much cut up, and traversed in all direc- tions by very narrow and deeply embanked ravines in the midst of masses more or less dense of Aleppo pines and green oaks, “These ravines are almost the only outlets for the transport of wood, in consequence of the difficulties which would be encountered, and the expense which would be incurred, in making more practicable ones on the rapid declivities, strewn with enormous masses of rock. There exists one so situated, called the Ravine de Saint-Phalez. The direction is from north to south, in the midst of a mass of Aleppo pines.in a state of growth more or less compact. ; “Tts length, and for four kilométres, or from the road from Cavaillon to Pertuis, to the domain of Saint-Phalez, of an area of about 50 hectares, forms the bassin de réception of the torrent. “This land is well cultivated ; there are no declivities too steep for cultivation ; it comprises vineyards, meadows, and arable land ; the soil is argillaceous. “The ravine of Saint-Phalez receives many affluents, the most important of which is that of the Combe-d’Yeuse, which joins it near the summit, where are some hundred métres of the cultivated grounds of which I have spoken. “The ravine de la Combe d’Yeuse is of much less considerable length than that of Saint-Phalez ; it is scarcely two kilométres. It is strongly em- banked, surmounted by steep declivities, covered with green oaks of eight or ten years’ growth, and with Aleppo pines of different ages. Its bassin de réception, of about 250 hectares, or 113 acres, comprises the whole slope, precipitately inclined, with a general south-west aspect; it is closed at the top by a deep bed of rock cut into peaks of the most imposing aspect. “The geological formation is absolutely the same, as are all the other conditions, at all the points which I have examined. In no part is to be seen either spring or appearance of humidity ; no water is seen excepting at the time of the storms or great rains, and this water soon passes away, with the differences which will afterwards be mentioned. At all other times these ravines are of a desolating aridity. “Tn the night of the 2d and 3d of September 1864 there fell a rather abundant rain over all this portion of the mountain. In the morning the argillaceous grounds of Saint-Phalez were saturated, of which evidence was found by anyone attempting to cross them. The ravine of Saint-Phalez, the receptacle of the surplus water, had flowed but slightly ; that of the Combe- d’Yeuse remained dry. “The day of the 4th September was very warm; a water-spout borne along by a south-west wind struck on the Luberon. Its passage did not last more than forty minutes ; but scarcely had it come when the torrent of Saint-Phalez became awful. Its maximum deliverance was about two cubic métres. It did not flow more than fifty minutes, but with an average delivery of half a cubic metre; it had then passed in all 15,000 cubic métres of water. Its height had been 0°04 m.; each square métre had received 40 litres, and the 50 hectares of Saint-Phalez 20,000 cubic métres. The ground had only retained 5000, which is sufficiently explained by their 92 | LITERATURE ON TORRENTS. argillaceous character and their state of saturation the night before. While the torrent of Saint-Phalez flowed, filled from bank to bank, seizing and carrying off rocks which had been employed to form a road which was believed to be safe against all contingencies, that of the Combe-d’Yeuse and all those traversing wooded lands remained dry, or gave only an insignifi- cant quantity of water. “Qn the slope opposite to that of which I have been speaking, in the valley of the Peyne, a carriage-road newly formed did not experience the least injury throughout the whole of the portion of it passing through the forest " of the domain ; but at its issue, on the lands of the Libaude and of the Roquette, it had been, so to say, destroyed. A cart loaded with faggots was upset and smashed by the waters, which flowed from all the cultivated slopes, and tore along, with the noise of thunder, at the bottom of the ravine. “My good fortune secured to me another subject of study on the same ound. “ On the 25th October following I went to the sale of the fellings of the Tarascon, where there fell an abundant rain. The next day (the 26th) the weather was clouded. I set off for the Luberon in the hope of arriving there at the same time as would a storm of rain, which I saw approaching. I arrived first ; the ravine of Saint-Phalez was still moist, from the passage in small quantity of the waters of the night before; they had served, as appeared, to saturate the lands of the domain, as had previously happened on the 7th [3rd ?] September. “JT had scarcely gone over two kilométres in the ravine when the water began to rush with great violence ; ten minutes later it precipitated itself in its ordinary canal d'ecoulement, completing the work of destruction begun in the month of September. The lands of Saint-Phalez had then absorbed but little or none of the water that day. “The storm was not of long duration—an hour at most. The time was unfavourable for collecting on the ground exact measurements, but I reckon that the torrent delivered, at its maximum, somewhat less water, perhaps, than on the 4th of September. The flood, however, was more frightful ; it swept away rocks with so much the greater ease that nothing had been repaired since the first storm, which had left the stones dug out, and without bond of cohesion among themselves. “To gain the forester’s house, which was on the slope of the left bank, it was necessary to make a long circuit—to go round the domain of Saint- Phalez, and to cross the grounds belonging to it, in which one sank to the depth of 0°30 métres, or 12 inches. Before arriving at my home I had still before me the ravine of the Combe-d’Yeuse, and I feared I should be stopped there by a new obstacle. I was agreeably surprised to find it dry. An hour after the storm the ravine of Saint-Phalez had ceased to flow. “Tt rained throughout the whole of the 28th without there being anything to remark similar to what had happened on the preceding days. The only effect of this was that, on the evening of the 30th, near the forester’s house, and at 200 or 300 métres from the ravine of Saint-Phalez, there was seen coming down, in that of Yeuse, a small fillet of clear water ; its volume increased perceptibly during three days, to diminish in like manner during the two which followed; its passage broke down a little of the foot-path which goes along the valley, but caused only a damage easily repaired. This foot-path did not present the same solidity of structure as that of the Combe de Saint-Phalez, built on enormous blocks of rock which had REVUE DES BAUX ET FORETS, 93 stood for several years, and which had allowed of passage with a waggon some days before its destruction by the storm in September. If the Combe- d’Yeuse had yielded as much water as that of Phalez, and if these two masses of water had come at the same time, the damage caused in the plain would have been considerable, and the Durance, which received these waters, would have been so much the larger. “Thus we have two torrents very near and under the same conditions— except that the basin drained by the one comprises 50 hectars of culti- vated lands, that of the other 250 hectares of woodlands. The first receives, and allows to flow away, the waters of the greater part of a storm in a few hours at most, causing thereby considerable damage; the second, which had received a greater quantity of rain, stores it—keeps it for two days— evidently retaining a portion of it, and takes three or four days to yield up the surplus, which it does in the form of a limpid and inoffensive stream, “The day on which I took the notes which I have copied in part I did not think they would ever be of use to me; what I had seen taught me nothing new; my old convictions had been simply confirmed, and I remained anew persuaded that it was imprudent to deny what the inhabi- tants of the country—better observers and more clear-sighted, when acting for their own interests or their own property, than is generally supposed— have long affirmed, supporting their allegations on abstract theories. What T had just seen in the Combe-d’Yeuse, however, had roused my curiosity. I wished to know if it had been remarked before, and that invariably. With this view I held a kind of inquest ; I interrogated an old warden and woodman, and wood-merchants of the country. “T will tell in a few words what I learned from them. “ Before 1840 the fellings of the Luberon were sold with power to bud the Aleppo pine ; the prescribed period of exploitation was ten years. “From 1823 to 1833 the whole of the Combe-d’Yeuse was exploited. The growth was composed principally of green oaks; the Aleppo pine was only found in clumps, often very sparse of trees, scattered over the whole surface. “In 1829, the year of the building of the forester’s house, the Combe- d’Yeuse yielded such a great quantity of water that enormous trunks of pine lying in the ravine, or on the slopes, were carried away by the torrent. The mason who built the house has confirmed to me the correctness of this last statement, telling me that the day after the storm the purchasers ran over the plain below the road from Cavillon to Pertuis to seek out their timber, scattered about and half-buried in the ground. It is probable that at that day the basins of reception of Saint-Phalez and of Yeuse being in pretty much the same conditions, the waters arrived at the same time in the canal découlement. It is easy to conceive what damage they occasioned to the rich cultivated lands on the banks of the Durance. “From 1829 to 1840 the Combe-d’Yeuse only twice yielded a little water. “ At this time the woods were on an average of twelve years’ growth ; the green oak-lopped and well-exploited had sprouted again with vigour, and were covering the soil, to which they already gave protection. It must not be forgotten that it was in 1840 that there occurred the great inundation of the Rhone, which drove the sheep from the Crau-d’Arles ; and the forest of Luberon afforded them shelter, which saved them from certain death. “ Some time before there had been made a barrage—barrier, or wear—at the outlet of the Combe-d’Yeuse where the passage is straitest ; it stopped 94 LITERATURE ON TORRENTS. a considerable quantity of water, estimated at 24,000 cubic métres by M. Cournaud, land surveyor; the warders bathed in it, and it was of such a depth that they could swim in it. Unhappily, this water coulc not be retained, in consequence of so many fissures in the rock and the rapid percolation through the soil ; and they broke down this barrage, which had been built with such great hopes, to facilitate the bringing out the timber of the last exploitation in 1856. “Tn 1843 there was still water in the Combe-d’Yeuse ; there was no more seen until 1856, but from this time onward the water flowed almost every year only in small quantities. But the year 1862 must be excepted ; although much less rain fell than in 1864, it delivered much more water into the ravine; but this it did without causing damage worth speaking of. “ The comparison of all these dates seems to me to supply valuable instruc- tion. If the woods be young the ravine flows every year, often causing thereby considerable damage. As their age augments it flows at intervals more and more remote, and ends in being almost completely extinguished. “ These conclusions will not astonish foresters who have been accustomed to the exploitations of copse wood. For, slight as may be the slope of the ground with a light soil, the annual fellings are cut into ravines by a single storm, whilst nothing like this is to be seen in the felling at its side, which has grown for 20 or 25 years, according as the one or other of these rota- tions of the fellings has been adopted.” In 1849 there appeared a pamphlet by A. Marschand, entitled Ueber die Entwaldung der Gebirge, which was published at Bern; and in 1872 was published, at Arbois, Les Yorrents des Alpes et le Paturage, par M. L. Marschand, Garde Général des Foréts, Ancien éléve de V Ecole Forestvére. The preparation of this treatise was undertaken at the suggestion of M. Faré, Directeur général de? Administration des Foréts. It embodies the results of observations made during a residence of seven years in the valley of Barcelonette, and during a tour of observation in the Austrian Alps, and observations made in Switzerland, whither M. Marschand had been commis- sioned to go to complete his study of the subject. The attention of M. Marschand was given, primarily and chiefly, to torrrents and the means to be employed to arrest and counteract them ; attention was also given to pasturing of flocks and herds on the mountains as the original cause or occasion of the destruction of forests, which destruc- tion of forests had been followed by the appearance of the torrents in the regions in which they are so numerous. Every facility was given to him by the forest authorities, officials, and subordinate employés, in the prosecu- tion of his studies; and he states that by them were furnished many of the documents and ideas embodied in his treatise. M. Marschand appears to have been led to conclude that the effects pro- duced by trees, observed by Surell aud others, was, primarily and principally, if not exclusively, produced by their roots; and by these modifying the hydroscopicity, capillarity, and permeability, of the soil and subsoil ; and that this they did even when this ground was rock. And from this stand- point he deals with the subject. Surell and others had given an exposition of what may be called the mechanical effects of the roots of trees in preventing the formation of torrents ; he, while accepting this, was led to conclude that there was more in this than had been evolved. LES TORRENTS DES ALPES, BY MARSCHAND. 95 After glancing at the natural history of mountains; at their primary condition ; and at modifications of this effected by aqueous influence, including disintegration by frost ; at the arrest of these by vegetation, and the resump- tion of the operation of these, which occurred consequently on the clearing away of forests, &c., he says,—‘ There is an action but little observed, but one which goes on with very great activity, in the decomposition of rock— it is that effected by roots. This influence has been studied by Julius Sacks, and reported in his Jlanuel le Physiologie vigétale. “In twelve days the roots of the phascolus multijlorus [the scarlet kidney- bean] has produced, on polished white marble, great markings, a demi- millimétre in depth, like the traces of an engraver’s tool; experiments made with other plants, and on other kinds of rock, give similar results. Of these twelve days, six were taken by the root in reaching the marble, and in the remaining six days these markings were made. It may be inferred that the presence of forests, which develope a great many roots, deeply penetrating the ground, will have for its effect. considerably to increase the riches of the soil, by expediting the decomposition and disintegration of the rock. If we think of the results obtained in a few days by the experiment in question, we may form some idea of the influence of forests actin throughout hundreds of years ; and we may be prepared to admit that the rocky subsoil of the forests, although protected against extreme atmos- pheric influences, may be disintegrated, at least as rapidly as if it had been exposed to the direct influence of the atmosphere, through the influence of the roots of trees. It is to this operation we may attribute the gently rounded forms of calcareous rocks covered by the soil of forests.” Citing next experiments by Thurmann, in which cubes of different minerals, thoroughly dried, weighing each 100 grammes, were immersed in water for five minutes, he states that these gave the following results :— Liassic triassic, compact jurassic, liassic triassic and oolithic limestones, granite, serpentine, basalt, dolerites, trachytes, &c., gave a mean absorption of 0°50 gramme of water. Similar minerals, including gneiss and com- pact marl schist, somewhat disintegrated and changed, gave a mean absorp- tion of 1:50 grammes; limestone still further decomposed, ferruginous oolites of Mt. Jura, liassic schists and grits from the Vosges, and eruptive rocks perceptibly changed, a mean absorption of 4 grammes ; variegated grits, green coloured grits, calcareous chalks, gravelly clay, and sands, 7 grammes ; and clays, Oxford marls, kaolin, an absorption of from 10 to 30 grammes. These observations he considered indicative of the absorption of water being proportional to the state of subdivision of the material composing the rock ; and the effect he resolved into their hydroscopicity and their capil- larity—the former, the power of each molecule of the rock to retain around it a layer of moisture difficult to withdraw—the latter, the property pos- sessed by many molecules of earth, to retain, in interstices by which they are separated, small globules of water. Apart from these, he treats of the permeability of soils as something quite distinct, and existing in very different proportions—as, for example, in oolitic limestones, which absorb and retain very little water, but which are very permeable by water, through abounding cracks and chinks, and vertical fissures, by which they are subdivided, in consequence of which water falling upon the surface of them does not remain there, but disappears in innumerable fissures, To such chinks the name Jésines has been given. Missing Page Missing Page 98 LITERATURE ON TORRENTS. “T make no mention of the influence of forests in regard to evaporation —in regard to the direct absorption of water—and in regard to the humidity of the atmosphere, &c. I take up one point of view alone of the torrential management of waters in the high mountains, and these relate to this only indirectly. “Tf a storm of rain beat upon a forest the whole of the water which falls is temporarily retained, all penetrates more or less deeply the soil without flowing on the surface ; and, it may be objected, if the subsoil is imperme- able the result will be the same. But the objection is without foundation. I shall suppose, what is frequently the case, that there is impermeable rock underlying the humus : all the water should arrive at this bed of rock and flow down, but the hydroscopicity and capillarity of this humus—of the ground—of the foliage—of the branches of the trees—in a word, of the material of which the forest is composed—will arrest the water to such a degree and measure as to regulate temporarily the delivery. “Tn support of what has just been said,” says he, “I shall cite an obser- vation made quite recently in the canton of Appenzel, in Switzerland. The torrent of Weissenbach formerly appeared in a swollen state at Weissenbach about three hours subsequent to the bursting of the storm on the mountain ; but since the woods have been destroyed—and this has only been done to a partial extent, and those destroyed have been replaced with a fine gazonne- ment—the floods appear at Weissenbach within an hour after the storm. In this we have a very striking illustration of the influence of forests, and of the gazonnement which has taken their place. And whoever has resided in the mountains will understand that a delay of two hours in the appearance of the flood, and in its protraction (which augments by four hours the period of flow), may suffice to prevent the most serious disasters ; for there everybody knows that the great danger from Alpine torrents arises from the suddenness, amounting almost to instantaneousness, of their flood. “T have glanced rapidly at the action of forests, in view simply of their effect on the water which falls on their surface ; but their function is by no means limited to this, for they serve also to arrest the waters which come from the pastures above them. They constitute in some measure a kind of immense and powerful barrage, or barrier, placed between the summit and the bed of the valleys. “In support of this allegation, I shall cite personal observations which seem to me conclusive. Never have I seen, during the most violent storms of rain, superficial flowings of water in the forests situated under pastures, though such flowings may have existed in the meadows at a greater eleva- tion than the forests; all the waters which these supplied were literally absorbed and retained by the forest soil. I except, intentionally, well- marked ravines, which coming from above traverse forests, for the question here is only of slopes somewhat uniform, or but slightly undulated ; it is evident that the soil of the forest will not absorb the water of a stream which traverses it encased in a bed. “J take, for example, a valley which rises to a summit line somewhat elevated. The end situated at a great height is formed entirely of pasture lands, which stretch out equally on the summits of the brows of the moun- tains ; at a lower level beneath these are the forests. The waters which fall into the cistern formed by the head of the valley rapidly accumulate, and give birth to a torrent which traverses the forest. On the contrary, that which falls on the pasture lands above the brows do not commonly reach LES TORRENTS DES ALPES, BY MARSCHAND. 99 the depth of the ravine: descending to the forest zone uniformly extended over the soil, they are there absorbed. “In a word, the zone of the forest absorbs generally the water flowing from the zone of pasture lands which correspond to it. Insupport of these observations, I appeal to all who, in the Alps, have observed storms of rain in the forest. I except water accumulated in ravines or depressions, which are in another condition. “ But the beneficent action of the forests does not limit itself to this ; the flow in the ravine may also, if it be not completely absorbed, be by them rendered less injurious if it should come to spread itself over a cone de déjec- tion in a forest otherwise covered with wood. I have observed, in connection with this, numerous muddy floods in ravines which, spreading themselves out in the middle of a forest, come out thence very limpid, depositing in it their slime, and leaving in it also almost the whole of the water. “The great forest of the Ofen, in the Grisons, has supplied me with many instances of this. The soil, composed of the dolomite limestone of the triassic period, is somewhat unstable ; in the middle of the pasture lands which surmount the forest there are formed every year numerous torrents, which to an enormous extent carry off the small pebbles, which are charac- teristic of the dolomite. All these torrents arriving in the forest, then expand and diffuse themselves, and very rarely do they penetrate to the bottom of the valleys. In the upper portion uf the Munster-Thal, I have seen on the right-hand side an enormous ravine, the muddy torrents of which are arrested by the forest. And the waters of the Munster, so well enclosed at this point, are a proof of the beneficial action of the forests. In fine, from the moment that the forests begin to retain the mud they retain also temporarily the greater portion of the water in which this was suspended, which are arrested by the enormous absorbent powers they possess.” Facts in accordance with some of these latter statements have been observed and recorded by others. M. Marschand makes the following remarks on The Injluence of Vegetation . on the Flow of Water :— “ GAZONNEMENT.—Many people suppose that on the steep parts of the Alps a good gazonnement would be enough to keep up the soil and put an end to.tor- rents. Experience has shown me that gazonnement alone is nearly always power- less to moderate sufficiently the action of water flowing over steep declivities, “T have been surprised at storms when passing through meadows fit for being mowed, situated at 2200 métres altitude—that is to say, above the forest region. After some minutes, if the storm was pretty violent, the water ran off the turf, collecting in the depressions of the ground, and forming small clear torrents. On the 17th August 1869, in particular, I observed in the upper basin of the Tinee, in the Maritime Alps, a storm of wind and hail which hardly lasted half-an-hour, but which gave rise in the meadows to a number of these little torrents, the junction of which would produce a very considerable rise in the Tinee. “ A storm observed at the same point in October 1868 threw immense masses of water into the same river in spite of the perfect gazonnement of its upper basin ; the same storm caused great havoc in the upper basin of the valley of Abrits, among the pastures on the hill of Grange-Commune. Two of my friends had great difficulty in crossing the meadows situated near the summit, so large were the torrents which had suddenly formed, 100 LITERATURE ON TORRENTS. “ All the places mentioned are covered with very good turf, and the goil is formed of grey schist. “The canton of Tessino is destitute of wood in most parts, but, as compensation, it possesses magnificent pastures which, in spite of the maddest mode of depasturing, preserve (thanks to the wonderful soil) their thick and perennial mantle of verdure. The inundations there are terrible, although at the lower end of the torrents are to be found lakes which retain the alluvial soil and moderate the rapidity of the rise in the rivers; the effect roduced by these lakes is very great but insufficient ; in 1868 the level of Fake Majeur rose 7 métres at Locarno, and in the public square the water rose to the first storey of the houses. “ Tt would be interesting and useful to ascertain the quantity of water which, falling with the rapidity of a thunder shower, would be sufficient to saturate a turfed surface, but the quantity is very small, and depends on the steepness of the descent. - This phenomenon is easily explained. Alpine turf, beat down by cattle, is formed of small plants growing close together, the interlaced roots forming a sort of felt. When rain comes it makes the rootlets swell, which, pressed together, imprison the soil and form a scarcely permeable covering, through which the water gradually passes only by means of capillarity and hydroscopicity. If the rain is slow and continuous these two properties are enough to permit all the water to pass through. If, on the contrary, it is violent, the water runs over the surface without being absorbed. “But, supposing the surface to be horizontal, the effect just described is also produced ; the excess of fallen rain, however, lies on the herbage to be gradually absorbed, for the quantity of rain retained by the herbage is in inverse proportion to the slope of the ground, and varies continually: “Turf, from the special point of view which we occupy, is chiefly useful in consolidating the soil; this end is partially attained, in so far as any surface whatever, when turfed, will always resist the direct action of the rain, but as a whole it is not: the excess of the water absorbed unites, forms little streamlets, and, according as the inequalities of the ground on which they recur are steep or narrow, the turf is attacked by the running water, the soil is laid bare at some one point, and in a few minutes there is the beginning of a ravine, which will always grow larger after every new storm if a remedy be not promptly applied. “To return to the subject, I would say that turf increases the capil- larity and hydroscopicity of the surface of the ground, but these two pro- perties are unable to absorb spontaneously all the rain which falls during storms, and the excess runs down the surface if the ground be steep, or lies on the top if it be flat. “These observations lead me to conclude that all flat surfaces may be turfed without inconvenience ; and that the turf on steep declivities will moderate very slightly the rising of the floods, “There is plenty of opportunity for making experiments on this point. Places for making observations should be chosen on the same kind of soil the surfaces of which have been examined, and where there is no water but from the sky. It can be easily done in the mountains. So soon as there are signs of a storm those employed should repair to such spots, there to measure the quantity of rain with a pluviométre ; and to measure, by means of barrages with rectangular sections, the quantity of water issuing from the basin where it is received ; and also to note the duration and nature of the storm, SUITE DE LETUDE, ETC., BY CEZANNE. 101 whether it be accompanied by snow or by rain, &c. These observations are so simple that the guards who live on the mountains will be able to make them. . “What I have mentioned will, I trust, make it very plain that on the Alps gazonnement alone is not enough ; this opinion is no longer disputed in Tessino, where, as I have already said, the herbage is exceedingly good ; observations on the rise of torrents in the ravines which descend from the pastures of our own Alps give the same results. “ Le BuIssoNNEMENT.—I have often spoken of buissonnement, or planting with shrubs, as being enough to put an end to Alpine torrents ; this opinion I now believe to be erroneous. Shrubs may undeniably be of great use— they may be able to cope with purely local accidents, but in no circum- stances can they be substituted for a zone of forest. I think I have explained before that Alpine forests create on the surface a bed of humus possessing great hydroscopicity. Shrubs do not supply similar results—it is in this they are inferior. They consolidate the earth well enough, but with rare exceptions there is not found under them the thick mobile layer which carpets large forests, and thus the soil receives atmospheric influences too directly. In conclusion, I may cite in support of my opinions the mountains cf Tessino, which surround Bellinzona ; which are well turfed, and covered with beautiful shrubs, but amongst which are found ravines and erosions. “ Looked at in regard to the regulation of the water flow, there is not much difference to be remarked between places which are turfed and those which are covered with bushes ; whilst in the upper part of the valley of Tessino, towards Airolo, there is proved to be an enormous difference between the rise of torrents in the wooded valleys and in those which are not wooded. “Les Forzts.—Forests are on a grand scale what meadows and shrubberies are on a small one ; their effects are—(1) The formation by their detritus of a highly hydroscopical bed, and in consequence of this augmenting the quan- tity of water retained by the soil; (2) The augmentation of the surface of the dispersion of the water; (3) The augmentation of the permeability and capillarity of the subsoil.” In 1872 appeared the Supplement by M. Ernest Cézanne, Zngénieur des Ponts et Chaussées, Representant des Hautes Alpes a UV Assemblée Nationale, to the work of M. Surell, published conjointly with a second edition of the work, and containing a review of treatises which had been published, and of works which had been executed, in the interval which had elapsed subse- quently to the original publication of that work. Tn this work, while holding that deboisement, or clearing away of forests, is not always and everywhere to be condemned, but is in many circumstances ~ necessary for agriculture and the promotion of civilization, and that the general reboisement of the Alps would be the ruin of the country, M. Cézanne states that the great service rendered by Surell was the disengaging and treating apart from the general question of forest science the special pro- blem, of local importance, relative to the effect of forests on water-courses, which, being carefully defined, was thus prepared for treatment according to scientific method. In an introductory chapter he gives a condensed history of deboisement, or the destruction of woods in France. In a second chapter he gives a careful discussion of the question,—Has the deboisement of France modified the mean annual temperature of the country either one way or the other, 102 LITERATURE ON TORRENTS. as ig maintained by opposing parties, which discussion he concludes with the statement that he deems it would be wise, in existing circumstances, to hold by these words with which Gay-Lussac replied to Arago, before the -Commission of Enquiry of 1836 :—“ According to my opinion there has not yet been obtained any positive proofs that woods have by themselves an actual influence on the climate of a great country, or of a special locality, or that they have an influence different from that of vegetation of every kind, The questions involved are so complicated, when we face them under the climatic point of view, that the solution of them is very difficult, if we may not say impossible.” The third chapter is devoted to the consideration of the effects of forests on the rainfall. In this he alleges that in so far as this is effected by mountains it is less the local elevation than the local inclination of a place by which the effect is produced, and that the effect of this is different according as the pluvial cloud may be ascending or may have commenced its descent ; and this, he contends, is an important element to be employed in the correction of pluviometrical observations. He considers that the effect of forests on the quantity of rainfall must be infinitesimally small, and that numerous corrections, some of which he specifies, must be made upon pluviometrical observations before they can be made available for a satisfactory solution of the question raised. Tn succeeding chapters are discussed evaporation, infiltration, rwdsselle- ment, or the source and flow of water in water-courses, with the action of forests on each of these, and the result of such actions, which he sums up thus :—“ This action depends on circumstances peculiar to each water- course, and even to each affluent. This action is proportionally more certain and more energetic according as the water-course is more torrential. “ But what it is impossible to deny, and is beyond all dispute, is the influence which forests exercise in conserving the soil of the mountains against being washed away. In doing this, and preventing the formation of ravines, forests modulate the flow of the waters. And this supplies the only certain criterion we have of the utility of forests in this connection.” The chapter which follows reports what was done in the ten years following the passing of the law of 1860, including the passing of the law in regard to gazonnement, with details of the circumstances which led to this ; which chapter he concludes with the remark—‘ After such testimony one cannot feel free to doubt that the operation is good, seeing that it satisfies everybody—the Administration, men of science, and the people.” In another chapter he reports the work done, and results obtained in connection with the artificial extinction of torrents, Then follows an analysis of a memoir by M. Guiny, sub-inspector of the exploitations of the mountains thus redeemed, which appeared in the Revue des eaux et foréts, for 1865, with remarks of his own in support of the proposal to substitute cows for sheep, and more especially for the immi- grant sheep from Provence, the pasturing of which is destructive and unremunerating. This is followed up by similar analyses, with remarks of Etudes sur les torrents des Hautes Alpes, par M. Scipion Gras, and of Memortre sur les barrages de retenue des graners dans les gorges des torrents, par M. Philippe Breton, and of Rapport au counseil fédéral sur les torrents des Alpes Sursses, inspectés en 1858, 1859, 1860, e 1868, par M. le Professeur Culmann— works relating chiefly to torrents to which gazonnement and boisement SUITE DE VETUDE, BY CEZANNE. 103 are inapplicable as means of extinction, as is the case with many which derive their floods from glaciers,-and which treat of the absolute and the relative advantages of dykes or embankments, of barrages or wears, and of artificial channels for drawing off the excess of waters,—while the last of them supplies not a little detailed information in regard to Swiss torrents similar to what has been cited in'regard to torrents in the French Alps. And in a concluding chapter the information obtained by induction through the study of the torrents of the Alps is applied to geological pheno- mena which find, or do not find, a satisfactory explanation in deductions made from what has there been seen. In this chapter he shews that extensive districts of the country, some of them far away from the Alps, show indications of torrential and glacier action, upon which, when this has once been seen, it is as impossible to look without this being seen, as it is to look upon the remains of extinct torrents in the Alps, referred to by M. Surell, without perceiving them to be such, when once they have been seen to be so in the light of M. Surell’s observations. The expansion of the theory is so very great that some preparation of mind may be desirable before taking up his views, and the more advanced views of others upon the subject, whether this be done with a view to accepting, or comparing and weighing, or rejecting them. This may be pleasantly obtained by a cursory perusal of the following little fancy sketch, embodied in a defence which he makes of graphic details of physical geography, embodied in the memoir by M. Breton, analyzed in his work. “M. Breton,” says he, “almost apologizes for pausing to describe effects so well-known in the mountains. But, apart from the circumstances that the delightful character of his demonstrations secures for him the favourable consideration of his readers, do not many pass by the most interesting phenomena of nature without observing them? And is it not delightful for a traveller when, enlightened by the instructions of a master, he knows how to account to himself for all the peculiarities of those distracted surfaces, and to decypher at a glance in these archives of stone the ancient history of the mountain 4 “This steep declivity is a cone of crumbled down earth which descends from that gap; this one here, less inclined, has been produced by an aval- anche ; that other presents the subdued slopes of a torrential cone. This small hill leaning its back on the mountain is an ancient cone which would fill up the valley ; near to the gorge a village conceals itself, the vane of the clock peers out from above massive domes of walnut trees, towards the base the river has lately opened a troncature or section of the cone by a rush upon it, and then she has thrown itself against the other side of the valley ; a recent cone has engrafted herself on the older, a little in advance of the exposed’ section ; not far from that a moraine, more ancient still, almost buried in the cone, carries back the thoughts to the times long past, when these fields, to-day so rich and animated, were like to the desolate fiords of Greenland, and slept enshrouded in a mantle of ice.” All this seems natural and sound ; we feel that it is not a mantle of fiction, but a mantle of fact which is being thrown over the scene, and we find pleasure in the reproduction of what was in the olden time, and in time much older than that to which that designation is generally given. But he (Cézanne) takes us over extensive districts of France, and shows us the same kind of things every where. Nor does he in doing so recede into the inaccessible, where we cannot test the correctness and verisimilitude of what he says. 104 LITERATURE ON TORRENTS, “ A journey of a few hours (says he) may enable any one, from the window of a carriage, to verify the greater part of the observations made. From the railway station of Hendaye, which is on the shore of the Ocean, may be seen on adjacent rocks the covering of loess, and the torrential pebbles. “Tn the cuttings towards Biaritz and Bayonne, the bank of gravel is well marked, and from place to place very deep and extensive. From Peyre- horade to Pau, the railway follows closely the foot of a terrace, the slope of which often presents a remarkable regularity. It is the base of a cone cast up on the tertiary deposit by the Gave de Lourdes. The town of Pau is built on the edge of this terrace. From the Place Royale we look down upon the valley of the Gave, some 30 métres, or 100 feet beneath ; opposite, on the left bank of the river, the undulating knolls of Jurangon are remains of the glacier deposits of the Gave d’Ossau ; on the right bank towards the east, and on to the mountains stretches in dimishing perspective the valley, divided in its primary plan by a small chain of low hills, crowned with villas and small umbrella-like pines ; these are testimonies to the work of erosion committed by the Gave when it opened up its channel and valley through its own deposits. The horizon is bounded towards the northeast by a straight line of regular inclination, which is the culminating ridge of the cone of Lourdes. “From Pau to Nay the plain is sown with rolled and water-worn pebbles. From Nay to Saint-Pé the grounds show, from time to time, the unmoved rocks covered with loess and glacier pebbles, and once and again terraces cut up by the Gave in its own deposits. From Saint-Pé onwards appear morame blocks, which continue to appear until Lourdes is reached, and the spaces between these moraines are filled with pebbles rolled by the torrents. Lourdes is the highest point of the railway, corresponding at once to the summit of an angle which formerly divided the glacier into two branches, and to the summit of the glacier-deposited cone ; the latter is on the hills which rise to the left of the railway station. The Bléout, with its erratic boulders, rises on the right of the station, and partially encloses the valley of Argelés. “On leaving Lourdes the road descends towards Tarbes by a riverless valley ; and between Lourdes and Adé there have been counted, in the rail- way cuttings, seven separate and distinct moraines, partially buried under the argillaceous loss and the torrential deposits. “The line proceeds for some way between the two cones of the Gave and of the Adour ; but thereafter the plain expands through the erosion effected by two parallel water-courses. The Echez, pretty far to the right, is still eating away a scrap of the cone of the Adour; while on the left bank the Mardaing is attacking the cone of the Gave, the fine regular ridge of which may be seen after passing the station of Ossun. “In approaching Jullian the railway passes through a cutting in descend- ing a terrace cut up by the Echez in the dejection of this torrent, which took its rise towards Adé from the eastern branch of the glacier. The strength of this torrent, now no more, is still testified by the dimensions of the blocks of stone which it has rolled down and spread over the plain. “From Tarbes to Tournay the tunnels and cuttings are cut under the loess of the Adour, and we traverse several open valleys following the crest of the cone. The rails at Tournay pass over the Arros, which flows between the glacier dejections of the Adour and those of the Neste, and rises, as the cone of the Neste, by an inclination of 034 along the valley of the Lene, SUITE DE L’ETUDE, EBTC., BY CEZANNE. 105 “At Capvern the railway debouches on the plateau of Lannemezan, where the view extends over a plain of varied contour, which is bounded! to the south by the lofty amphitheatre of the Pyrenees, and which sinks away towards the north and is lost in the horizon. We are then ‘under the col’ by which the loss was spread out, and a momentary glance may be had of the valley of the Neste, whence the glacier degorged. “The culminating point is near the station of Lannemezan ; it is there, near this summit, and in accordance with the torrential character of the phenomena, that we see the largest sized pebbles of the kind seen in travel- ling thither from Tarbes, some of them larger than a horse’s head. And it’ is necessary to re-descend so far as Montréjeau to find ina moraine, brought to light by’a cutting, blocks of a size comparable to that of those found in this culminating ridge. Gia “From Montréjeau to Toulouse, and more especially in the plain of Muret, the plain is bounded towards the left by the regular formed ridge of the cone of the Neste. The hills are cut in terraces, which- become less im- portant as they recede in distance from the cone. - Montréjeau and Saint- Gaudens are built on the edge of a slope of water-rolled blocks, some of the last traces of which may be recognized at the gate of Toulouse.: ; “Tf, quitting the main line at Portet-Saint-Simon, we go up the valley of the Ariége, we shall not be long in finding unequivocal evidence of tor- rential action. In the environs of Pamiers the plain is completely covered’ with blocks of stone, perfectly rounded, which the husbandmen have collected into heaps all around the cultivated spots, seeing which one could’ almost imagine himself on a recently grubbed cone of a recent torrent like! that of Embrun. These blocks are found of increasing size as we get higher, and in the station of Foix may be seen, in the garden of the station master, most beautiful chips of glacier blocks, with streaks’ and other indications of friction produced by glacial action. The terminal moraine was in these barrages or dams, and the minute study of the environs’ permnits, if it do not suggest, the supposition that in the glacial period the: beautiful elliptical basin, at the bottom of which flows the. Larget, which at Foix falls into the Ariége, was repeatedly filled and emptied, forming an important lake and formidable floods.” te ‘In a foot-note it is stated,—“The town of Foix and its picturesque chateau are situated on what looks like the gate of a sluice closing the strait gorge by which the Larget debouches ; but behind this gate the basin opens up and ramifies on a large scale; and this basin, closed by a barrier near the extremity of the glacier, was in circumstances. exceptionally favourable to the production of a lake and of débacles, or breakings: up, emptying it in a great measure of its contents.” i SR Blah From the study of such and such like phenomena, M. Cézanne has been led to conclude that there must have been a period when torrential action has been much more stupendous and much more extensively diffused than at present. eam ane rare But: M. Cézanne alleges that there are indications, no less marked, of glacial action in deposits underlying some of these torrential deposits.:., He. remarks that the theory of glacial action, considered as a chapter of geology, presents this peculiarity—that all the phenomena embraced, by it, and all the circumstances in which they occur, may be observed in our own time. There is no difference, excepting in the scale of magnitude of the phenomena, which has been greatly reduced. ref 106 LITERATURE ON TORRENTS, The action of glaciers has been studied in the Alps; results obtained have been applied to the phenomena presented by and in connection with the parallel roads in Glen Roy; these have been satisfactorily shown to have been produced by glacial action, exhibiting on a grand scale the same phenomena as are to be seen in the valley of Bagnes, marking out what must have been the banks of the ancient lake of Giétroz. He quotes a paper by M. Ch. Martins, which appeared in the Revue des Deuw Mondes for March 1867, in which it is said,_—‘ Throughout almost the entire length of the valley of Glen Roy—that is to say, for ten miles and upwards—there.may be traced on the opposite declivities three terraces or parallel banks, perfectly; horizontal and corresponding exactly on the two sides of the valley. From a distance they are distinctly visible ; when reached they are found to be a pebbly surface from 10 to 60 feet wide, the slope of which is less steep than that of the mountain above and below. The lowest of the terraces is 750 feet above the level of the sea, the second about 210 feet higher, the third upwards of 80 feet above the level of the second,—all terminating at the head of the valley on the col which separates it from the valley beyond. “Tn 1840 Buckland and Agassiz visited Glen Roy, and perceived that temporary barriers to the flow of water could alone account for the formation. of these level lines. Glaciers coming successively to close up the one or the other issue of the valley, the stream which ran through it would form a lake, which would flow by the col towards which the terrace inclined. Agassiz recognized polished and striated rocks and the ancient moraines which he had learned to distinguish in the Alps; and subsequently Mr Jamieson has given a chart and details confirming completely the view of the illustrious Swiss naturalist. “Mr Jamieson carries back the formation of these terraces to the close of the second glacial period, when it was due to an oscillation of the. glaciers descending from Ben Nevis and the surrounding mountains. These barriers have barred up, one after another, the valley of Glen Roy and the neigh- bouring valleys. The waters, stopped in their flow, have formed lakes at different levels, determined in each case by the height of the col which closed the extremity of the valley opposite to that barred up by the glacier. The entireness of the terraces prove also that subsequent to the formation of these Scotland has never been submerged.” And M. Cézanne goes on to say,—“ If this theory be correct, it follows that we may expect to find at the débouche of each of the great valleys of the Pyrenees and of the Alps masses of loess, deposited in accordance with the characteristic forms of torrential deposits ; and the dimensions and com- position of which may be in accordance with the immense duration of the glacial period, and so in accordance with the greatness of the phenomena to which this has given rise. “At the foot of the Pyrenees there exist such deposits ; if not most. con- siderable, they are at least most perspicuous. Let us ascend some height such as the Pic du Midi of Bigorre, or the Cap of the Col d’Aspin, the ascent of which is very easy ; from this elevated point the observer, turning to the north, can freely cast his eye from the west to the east, over a vast plain which rounds itself off at the horizon, as does the sea, and the bleak fawn colour of which contrasts strongly with the green and sombre wall of the Pyrenees. “This general effect is pretty well rendered by the chart of the Ztat- SUITE DE LETUDE, ETC., BY CEZANNE. 107 major, on which one may, besides, recognize the smallest undulations of the ground, which to the observer are flattened by the aerial perspection. According to the chart it is not a compact plain which stretches from the foot of the mountain, it is a series of vertically rounded plateaux, or of flattened cones, the summit of which is at the gorge of each important valley. “The two sheets of this chart, representing the districts of St Gauden’s and Tarbes, placed side by side, represent in a striking manner, to whoever may have seen well-marked torrents, three vast cones of déjection which débouche from the valleys of the Gave, at Lourdes—of the Adour, at Bagnéres —and of the Neste, at Héches.” The cones thus represented are furrowed by numerous water-courses from the mountains ; and they themselves to some extent intersect or cover one another. Full details are given, with tabulated measurements, and references to a coloured geological map of the district. And having referred to difficulties which had been experienced by others in attempting to account for all the phenomena, he goes on to say,—‘ That these cones have come out from the gorge’s entrance, which are guarded by them, a single glance at the map suffices to show ; and an examination of the places themselves leaves no doubt upon the subject. “The glacial origin of these vast deposits is not less certain. In each valley it is possible to follow, from the moraines which remain intact on the extremities of the cones, step by step, the progress of the rocky frag- ments which little by little lose their glacial characteristics, become rounded, diminished in size, reduced to ordinary gravel, or even to clay or glacial mud. In the valley of tlie Adour, for instance, facing the village Santa Marie, are two conjoined gorges, descending, the one from Tourmalet, the other from the Col d’Aspin. Between these two gorges, and overlooking the con- fluence, is a terrace or bank; the slope of which, seen from below, recalls by its irregularity a gigantic railway embankment. If we trace this embankment, following it along the road which leads to Luchon, we soon discover, on the slope above this, a wood which imperfectly conceals a con- fused mass of enormous blocks called the Moraine de Grip, recognized at once as a moraine, such as may be seen near a glacier of the Alps. In this picturesque spot the Adour has cleared for itself a passage among the blocks, some of which, from their forms and size, may be compared to houses ; the Pre du Midi and the Pic d Arbizon, each at the bottom of one of these gorges, look down from their azure pyramid on this scene of disorder, where their ruins lie confounded. “ On leaving this, on to Bagnéres, there may be seen, on the two sides of the valley of Campan, the traces of a glacier: it must have gnawed, on a former time, at the vertical wall which rises on the right ; while on the left a series of terraces mark the different levels of the moraines, and the torrential alluvia deposited along the glacier. “Even at Bagnéres we are still in a country full of glacial ground : half- rolled blocks, in size to be compared to a sheep or sack of corn, lie about everywhere ; they encumber the bed of the Adour, form heaps along the highways, and enter into the construction of the walls. Towards the sum- mit of the cone—that is to say, on the hills of the right bank—they are very numerous, and also quite as large as in the valley ; but on leaving this point they diminish rapidly in size, following the same law of decrease in the clay of the hills as on the floor of the valley : twenty kilométres below, 108 LITERATURE ON TORRENTS, setae Ea niey Sh PE, te" oe ee oe ee Pee Raat ee at Tarbes, they have, scarcely the size of a man’s head; and towards Mont- de-Marson we meet almost exclusively with clay covered over with the sand of the Landes, borne thither probably, by the wind, a “The clay itself presents alternating colours.;,it is yellow, ochre coloured, or bluish ; and near Bagnéres we can in the trenches recognize some sort of stone which would furnish some one or other of the colours. By digging out blocks in all stages of disintegration, we may be said to see in actual operation the manufacture of clay. At some places a cutting in the ground presents the appearance of mosaic work, in which granitic pebbles, perfectly recognizable in their rounded forms, but softened by time, may be cut like butter, or rather like nougat [a cake made of almonds and honey], each of them leaving still recognizable, in spite of its decomposition, the rock from which it had been torn. “The cone of the Gave supplies similar facts ; it is isolated on all sides ; its head may be said to be in the air. The glacier which produced it would meet at Lourdes, on coming out of the valley of Argelés with a small mountain of schist, which would necessitate it to divide itself ; the exterior branch would direct itself towards where Tarbes now stands, extending as far as to Adé; the other branch would descend towards the position of Pau, reaching as far as Saint-Pé. Between the two branches would be turned off the loess ; so the summit of the glacial cone would rest on the schistose mountain in the angle formed by the two branches of the glacier. At the time of the retreat of the glacier all the waters of the valley of the Argelés were united towards the west in the Saint-Pé branch ; and the other branch, that of Adeé, is still a void valley without a river—the railway from Tarbes to Lourdes has been constructed there ; but this valley, devoid of a single considerable water-course, is full of torrential indications. “The valley of Argelés has been the subject of special study by MM. Ch. Martins and Collomb, indefatigable explorers, who, after having dwelt on the glaciers of the Alps in the Hotel mouvant des Neuchatelon, have sought, from Spitzbergen to the Sahara, the traces and the causes of the glacial period. These savants thus sum up their memoir, published in Bulletin of the Societe géologique de France, 2 série, t. xxv., p. 141, seances sur, 18th November 1867, and Mémoires de lAcadémie des Sciences de Montpelier, t. vii., p. 47 :—“To sum up these observations, we have ascertained in one _ of the principal valleys of the Pyrenees—the valley of Argelés—the _ existence of an old glacier of the extent of 53 kilométres, which shed its terminal moraines on the sub-Pyrenean undulating plain, and extended to within 15 kilométres of Tarbes, with an altitude there of 400 métres, about 1350 feet,—its point of departure being at a mean altitude of about 3000 métres, 4000 feet, the mean slope of its surface being 1 of 0.039. “ This glacier, including its affluents and its higher xévés,—in a word, its hydrographic basin—would cover an area of about 1:400 square kilométres, or 140: hectares. ‘“ The thickness of the glacier reached, at Gédres, 850 métres ; at Saint- Sauveur, 800 métres ; at, Pierrefite, 675 métres; at Argelés, 600 métres ; at the Pic de Jer, near Lourdes, 412 métres. . “The summit of the Beout, a conical mountain which rises above Lourdes in the middle of the valley to the height of 792, was covered by the glacier ; and even from the railway station of Lourdes may be seen distinctly, in profile against the blue sky, the erratic, boulders, scattered over the ridge of the mountain, at an elevation of 450 métres, 1350 feet, above the Gave. SUITE DE L’STUDE, ETC., BY CAZANNE. 109 “In the cutting from which has been obtained the material for the embankment on which stands the railway station have been found, with _. their characteristic fossils, limestones conveyed undamaged from the Cirque .of Gavarnie, and, side by side with these, blocks torn from the granite summits of Cauterets. The scientific explorers cited have given with their memoir a longitudinal profile of the glacier, and a chart of the terminal moraine. | ; “Tn studying,’ say they, ‘the traces which the glacier has left upon the _ soil, we have seen, that it comported itself as do all the glaciers known; it transported materials of great bulk, and at the same time minute debris, _ Which we find in the form, of moraines exactly in the place which is assigned to them. by the accepted laws of the movement of translation of glaciers, , and taking in these an arrangement or disposition which excludes every thought of other mode of natural transport. .. “At the same time the glacier has polished and scratched the resisting rocks with which it was in contact,’ (and it should be admitted that with _ the thickness given above [I-am quoting M. Cezanne] that the rubbing and _ friction of the glacier, with a pressure approaching to 1000 tons per square métre, prolonged throughout some hundreds of ages, would suffice to account for the erosion of a valley many hundreds of métres in depth). ‘Then, in the third place, the mud produced by the continual friction of the ice against the rock, finally ejected by the waters produced by the melting of the glacier, and by the glacial torrents, have contributed to form the principal material of that less which covers the place far beyond the périmétre of the ancient glacier.’ “One might, were it not necessary to avoid repetitions, give proof as demonstrative in regard to the cone of the Weste which forms the plateau de Lannemezan. This plateau is a vast deposit of less brought out from the valleys of the Neste; but a noteworthy circumstance is, the less important of these two- valleys, that of the este, has supplied the uppermost dejections; its cone has partially covered up that of the Garonne, and the great river has been turned out of its course by its affluent. All the strange windings of the Garonne, and of Saint-Bertrand de Comminges at Montréjeau, explain themselves at once on the spot by the strongly characterised moraines which the Luchon railway has exposed. Me Much less ramified are the other valleys of the Pyrenees—those, for instance of the Nivelle, of the Nioi, and of the Joyeuse ; those of the Gaves, of Mauléan, of Aspe, and of Ossau—that more especially of the Ariege—des- cending from less elevated summits, have had their glaciers and their torrential débacles proportionate to the local circumstances.” These. are but specimens of numerous details given, most of them with measurements and other indications of precision such as science demands, of the district thus traversed, of the districts beyond, of the Alps, of the basin of the Rhone and its affluents, with references to what is to be seen in the basins of the Po, the Danube, and the Rhine,—producing an impression that the whole of these districts, together with much of the intermediate region, is covered with torrential deposits of a magnitude and extent far surpassing those of any which the engineer of modern ,times is called to treat—reminding one of the statement, “There were giants in those days.” 110 LITERATURE ON TORRENTS. And in view of the whole he (M. Cézanne) is led to conclude that this which he is disposed to designate the torrential geological era must have been immediately posterior to what is known as the glacial period. To the consideration of the phenomena illustrative of this point, and of pheno- mena occurring during the alleged era, is devoted the penultimate chapter of the work. More immediately connected with the subject of rebovsement is the following réswmé given by him of the whole series of phenomena brought under review :— “There may be given in a few words a résumé of the whole series of these phenomena. “The mountains are the result of a series of upheavals following one upon another in the same region. A final agitation gave to the different chains of these the existing elevation ; it elevated the summit and opened up deep fissures or divisions, which have become the valleys of the present time. From the time this occurred the waters began to fashion the thalwegs, following the line which best suited them ; wearing down outlets and filling up basins. It is necessary to admit, or to assume, that the depth or thick- ness of the alluvial deposits in the bottom of certain valleys—for instance, those of the Istre in the Graisivaudan, or of the Rhine in Alsace,—is to be reckoned by hundreds, and perhaps by thousands, of métres or yards ; for even yet certain lakes existing in depressions of the Alps have their bottom below the level of the sea. “ After a long series of ages the mountains assumed the leading features which they now exhibit, when, the climate changing, great glaciers carried on actively the work of erosion; these have planed away escarpments, and fashioned into something like horizontal lines the rocky belts of the valleys. “ Débdcles, or inundations, from the escape of the waters of pent-up lakes, and deluges resulting from the tremendous rains of summers on the extensive fields of ice, have carried away and deposited in the principal valleys in certain favourable places, but more especially at the débouchures of lateral gorges, the masses of loess which have formed cones in the higher plains, and in which the water-courses have subsequently dug out the secondary valleys. “ At a later period, after the melting away of those glaciers, the torrents seized upon the bared mountains ; and without restraint they have dug out their basins, and have again taken up the materials disintegrated by the glaciers, and deposited these in the gigantic cones which give to certain regions a physiognomy peculiarly their own. “But after a time the forests, spreading by degrees, stifled the waters under a mantle of verdure ; the torrents became extinct,—an era of peace and of comparative quiet supervened in the mountains; then the tribes of men, who during the glacial period rambled over the low-lying plains, in company with the reindeer, the aurochs, and the bears, began to spread themselves in the high-lying valleys. The most ancient settlements were made at the gorges of the torrents, towards the summit of the cone; in point of fact, there are to be found in the mountain valleys very fow of these gorges in which we do not meet either with an existing village or with an ancient ruin. “Tn this location, which was then one favourable to their pursuits, the primary inhabitants could profit by the exceptional fertility of the cone of LES TORRENTS, ETC., BY COSTA DE BASTELICA. til deposits ; they had nothing to fear from the principal river, which flowed through the lower-lying lands, nor from the torrent, which was then extinct ; they commanded the plain, and found themselves at the gate of the moun- tains ; the adjacent gorge supplied them with water, the forest supplied them with wood, the rock supplied them with stone, and their flocks spread themselves over the verdant ridges around them. “Little by little, a reckless use of the forests and of the pasturage disturbed the equilibrium of the natural forces; and now the old sore is re-opened, and anew, by man’s deed, the mountains are inoculated with the leprosy of the torrents. The evil has gone on increasing during prolonged ages of disorder and recklessness ; the position of the cultivated grounds, and of the villages established at the débouché of the torrents, has now become critical in the extreme ; and unless we go back, as we have done, to the olden times, we are unable to account for men having taken up their dwelling in the spots, of all others, which at this day appear to be those which are more immediately threatened. “But at last an era of reparation begins; and, thanks to the eminent men who have in byegone years given their mind to the work, the next generation may hope to see the final decline of the modern renewed Torrential Era.” In 1874 was published Les Yorrents leur lows, leur causes, leur effets : Moyens de les reprimuer et de les utiliser : leur action geologique universelle, par Michel Costa de Bastelica, Conservateur des Hauax et Foréts. This work treats of another aspect or of another department of the subject than any discussed in the treatises already mentioned, which the author designates,—Le phénoméne torrentiel, or la torrentialité ; and thus is opened up another chapter of the natural history of torrents. “The question raised by torrents,” says M. Costa, in the introduction of the work, “is a very complex one. Behind the technical questions embraced by it, there are others which connect themselves with the forest economy, and with the pastoral occupations and the agriculture of the inhabitants of the mountains, and which involve serious difficulties of administration and of legislation. To operate on the basin of torrents brings one in contact, and sometimes into collision, with the requirements and the customs of the population. The two spheres of thought are quite distinct. The technical element of the question is admitted to be the more important of the two, and it is made the basis of the system of operation. I shall, therefore, con- fine myself exclusively to it. It will be easy to remove the difficulties of another kind, which beset practical operations under the requirements of the case, when it shall be demonstrated by science, and established by experience, that it is possible to put a stop to the outburst of water-courses by a combination of simple works, comparatively inexpensive, and wisely- devised conservative measures. “With this view I desire to give synthetically the fundamental idea of the new torrential theory. “Tt has struck me in all preceding discussions, in regard to hydrology in- general, that they relate almost exclusively to the débit, or quantity of water passing or delivered; it is admitted that they take into account the materials borne along by the currents at the time of floods; but on the whole the supposed cause of inundation is always spoken of as the excess of the delivery over what it is at other times. All the discussions which have ~ lig LITERATURE ON TORRENS. taken place, and in which the most eminent savants have taken part, have been confined to that of causes which could ‘act on the delivery; and the whole discussion has come back to that of the permeability or impermeability of the soil. Even the efféct of forests has not been studied beyond what the consideration of them from this point of view required. All of the researches which have had for their aim to enable us to combat inundations, have had no other object but an action to bear on this delivery. All who have written on the subject have reasoned and made their calculations as if, at the time of an excessive flood, nothing was occurring but an augment- ation of the volume of the current, without any variation in the hydraulic law by which it was regulated. I have no hesitation in saying I con- sider this way of looking at the subject erroneous; and it is’ at this point that I take my departure from those who have preceded me—on a new enquiry. “From my point of view there is seen to be something more than simply a variation in the delivery. At the time of a great flood, when a current— be it great or small—bears along considerable solid masses, consisting of earth and stones of all sorts and sizes, a peculiar phenomena of special importance is evolved. This is a perturbation, more or less marked, in the progress of the current, and in the laws by which it is regulated ; and this it is which I call the torrential phenomenon, or, if a word must be created under which to speak of it, the torrentiality—an action of perturbation which is the greater in proportion as the secondary causes by which it is produced—namely, the solid matters borne along—are the more considerable. “From this point of view, the most furious torrents of the Alps are seen to be only extreme cases of a general phenomenon, which is produced more or less imperceptibly, or more or less distinctly marked, in all currents of water which are not perfectly tranquil in their flow. “The characteristic effect of this perturbation is an instability in the. course of the stream. “ When a current of water does not bear along solid matter, whatever may be the volume of water, the flow is effected with great stability in accord- ance with hydraulic laws. Sudden variation in the delivery, in raising or lowering the level, produce variations in the rapidity of the flow; from this there is thus a certain consequent perturbation ; but the action of gravita- tion, in its omnipotence, being constant, and this accommodating itself to the resistances due only to friction, the stability of the stream tends uninterruptedly to maintain itself. To a rise of level there being a corres- ponding increase of rapidity of flow, it is rarely the case that such waters rise higher than the banks. “The perturbation produced by solid material borne along is, on the other hand, very serious. If the substance of the current be very greatly changed in consistence—for example, if for a limpid water, possessing all its fluidity, there be substituted a viscous liquid—if, further, the torrent ‘be’ required to perform the mechanical work of conveying a certain quantity of solid matters—the conditions are greatly modified. In the first place we have no longer simply pure water, but water subject to every degree of variation in so far as fluidity is concerned ; and thus the work of transport imposed on the current developes resistances which are subject to every degres of variation. From this birth is given to an extreme instability in the current, or in other phrase, to torrentealzty. TORRENTS, ETC., BY COSTA DE BASTELICA. 113 ‘Experience shows that this perturbation, produced by second causes, exercises on water-courses a much more powerful action than that proceeding from simple variations in the quantity of water delivered. “In the great torrents of the Alps, which bear along at the time of great floods enormous masses of material, from the grain of sand to the largest blocks of rock, and which, moreover, are extremely muddy, the perturbation is such that the laws of hydraulics would appear at times to be entirely reversed, and to produce effects diametrically opposite to what are produced in a normal condition. For example,—the bed, instead of being concave, is convex ; the current, instead of following such depressions in the soil as offer the most rapid declivity, tends to raise itself, and to follow the pro- minent points in the ground. The surface of the water itself is convex; the most extraordinary dynamical effects are produced ; and the water-course ——a prey to a veritable revolutionary state of things—becomes the picture of the maddest instability. “We have there, I repeat, an-extreme case of the torrential phenomenon, and one the study of which is pre-eminently adapted to reveal to us the laws by which it is regulated ; for, though less remarkable, this perturbation is nevertheless perceptible in the currents of ordinary streams which bear away solid matter when in flood. This formidable phenomenon betrays itself by certain indications. The surface of the stream tends to assume a convex form ; it is furrowed with currents which change their position with great mobility and varying rapidity. The principal current, instead of establishing itself in the deepest part of the bed, tends, on the contrary, to follow the line of the highest parts of this, and to invade the banks of gravel, if there be such there. In rebound from the normal state the greatest rapidity of flow is along by the banks, and this is one cause of the erosion of these. “Tt is evident that these are effects which cannot be other than the product of secondary disturbing causes, since it is physically impossible that variations in the quantity of water passing along could be the producing cause of any such instability. ‘A trained eye, morever, can judge at once, by the appearance alone of a water-course, what is the degree of torrentiality to which it is subject. “ First, when the banks are, through a stretch of some length, covered with verdure to the water edge—or when the willows allow with impunity their branches to be borne along by the current—it is a certain sign of great stability and tranquilityof flow. If, on the contrary, the banks are despoiled of vegetation, and show traces of erosion—and further, if there are to be seen here and there banks of gravel—this is symptomatic of the first stage of torrentiality. “These indications become more and more pronounced, according to the special régime of each water-course ; and when, as in the Durance, the tor- rential phenomenon attains a great degree of intensity, the water may be seen straggling over immense plains of pebbles, and dividing into many branches, which change their position on the smallest increase of flood. “The condition and appearance of the islands formed by these branches present also a certain characterestic of greater or less stability in the régime of a water-course. When these islands are covered with old trees, and better still, if people have made up their mind to dwell on them, although there be occasionally great floods, it is a sign of great stability. If, on the contrary, these deposits are devoid, or despoiled, of vegetation, or have not M 414 LITERATURE ON TORRENTS. even acquired that dull tint which prolonged exposure to the air gives to them, it is indicative that the instability is very great. “The existence, then, of a torrential perturbation, attributable to matters borne along, is demonstrable. But more than this, this perturbation is subject to laws as constant as those which regulate the flow of water. The a priort proof of this is the form taken by deposits which are the products of this action. “ Nothing is more irregular, to all appearance, than the floods of the great torrents of the Alps. Those who have read the impressive descriptions of them given by M. Surell, know that they look like chaos: blocks of stones rolling along with powerful crashés, knocking one upon another, and a current black as ink, bounding over all obstacles, and spreading itself with extreme mobility over a widely extended surface without being able to fix itself any where. One is ready to believe that this enormous body of stones, borne off by the waters, is about to be scattered abroad at hap-hazard, and to form a confused mass, setting at defiance all rule; on the contrary, it is a curious fact of immense compass, that though the torrent, in pursuing for ages its work of clearing away in the mountain, anc of embanking in the plain, may have multiplied indefinitely its floods and its transports of material, the constant result of this continuous action—the one completed result of all these elementary embankments—that which is designated the hit de déjection—has assumed a geometrical form of the most perfect regul- arity! The determining of the geometrical law, by which the contour of these deposits with its numerous distinct characteristics has been regulated, presents considerable difficulties. I shall afterwards state what is my opinion on this point; but, whatever that law may prove to be, there evidently is some such law; and it is enough, at this stage of the discussion, that this has been established.” Alleging, then, that we may conclude with certainty that that work of the torrent, in appearance so irregular, has been governed by laws, and these the laws of torrentiality, he goes on to say, that it is desirable to determine what these laws are, as they are likely to throw some light upon the problem of inundations, and to indicate a rational solution of this, while the solution of the problem is of no small interest to the science of terres- trial physics, and even to that of universal cosmogony. Tn accordance with what is stated by M. Costa in regard to the con- vexity of the flood of the torrent, when charged with earthy matter, are the observations of M. Surell in regard to the convexity of the lit de déjec- tion, the last form taken by the suspended earthy material as the water subsided, though this convexity may be otherwise accounted for. Some- thing similar may be observed in a flow of treacle, or of tar, or of quick- silver, or other molten metal; but something similar may be seen also in a very rapid flow of water comparatively pure. By Marsh it is stated, in a foot-note appended to a passage in his treatise on Lhe Earth as Modified by Human Action,—“ Many physicists who have investigated the laws of natural hydraulics maintain that, in consequence of direct obstruction and frictional resistance to the flow of the water of rivers along their banks, there is both an increased rapidity of current and an elevation of the water in the middle of the channel, so that a river pre- sents always a convex surface. Others have thought that the acknowledged greater swiftness of the central current must produce a depression in that TORRENTS, ETC., BY COSTA DE BASTELICA, 115 part of the stream. The lumbermen affirm that, while rivers are rising, the water is highest in the middle of the channel, and tends to throw float- ing objects shorewards ; while they are falling, it is lowest in the midcle, and floating objects incline towards the centre. Logs, they say, rolled into the water during the rise, are very apt to lodge on the banks, while those set afloat during the falling of the waters keep in the current, and are car- ried without hindrance to their destination; and this law, which has been a matter of familiar observation among woodmen for generations, is now admitted as a scientific truth.” A phenomenon similar to that reported by the lumbermen of America may be observed in the rising and falling of mercury in a barometer tube. When rising, the surface of the mercury is convex; when falling, it is con- cave ; and so constantly is this the case, that directions have been given to observe whether the surface be convex or concave, to determine, irres- pective of the pointer, whether the mercury be rising or falling. The explanation is to be sought for in the relative strength of the attraction of cohesion keeping the particles of the fluid mass together, and the attraction of adhesion attaching them to the surface of the confining body, together with a third element, that of velocity of movement, which may be relatively different in its effect upon the two attractions named. This explanation of how the phenomena reported are brought about, taken in connection with phenomena which are cited by M. Costa, enables us to see how it may come to pass that destructive effects on the banks of rivers are frequently produced by the floatage of timber. In many cases the injurious effects produced upon lands by the clearing away of forests are increased by measures adopted in bringing the felled trees out of the forest, and in sending the timber to its first destination. By Marsh, in speaking of a common practice followed in America and elsewhere, it is said, — The lumbermen usually haul the timber to the banks of the river in the winter, and when the spring floods swell the streams and break up the ice, they roll the logs into the water, leaving them to float down to their desti- nation. If the transporting stream is too small to furnish a sufficient channel for this rude navigation, it is sometimes dammed up, and the timber is collected in the pond thus formed above the dam. When the pond is full a sluice is opened, or the dam is blown up or otherwise suddenly broken, and the whole mass of timber above it is hurried down with the rolling flood. Both of these ways of proceeding expose the banks of the rivers employed as channels of floatation to abrasion; and in some of the American States it has been found necessary to protect, by special legislation, the lands through which they flow from the serious injury sometimes received through the practice described.” And, in refereace to the bringing of felled trees out of the forest, he says, in an appendix,—‘‘ The methods of transporting timber employed by the lumbermen in the Alps are often more destructive than the baring of the soil. Forests frequently grow in Alpine glens, or other mountain localities, inaccessible to wheeled vehicles or even to sleighs. In such cases the timber is sent down by slides, which, if long used, become the beds of new torrents, or it is conveyed to larger streams by the method of floatation described. ee “The Rapport au Conseil Fédéral sur les Torrents, des Alpes Suisses inspectés en 1858-63, published at Lausanne in 1865 [that commented on by M, Cézanne] gives a great amount of information respecting this scourge and 116 LITERATURE ON TORRENTS. its causes, among which the practice of floatation is particularly noticed. The amount of damage done to the commune of Campo, on the Rovana, (a tributary of the Maggia, in the canton of Tisino) in great part from the effect of floatation, is most striking (Rapport I., pp. 7-13). The force of the torrent Rovana has been augmented to such a degree by baring the soil, and by suddenly opening the dams near its sources, that in the course of four years it excavated below the village a new channel one hundred feet deeper than its ancient bed, and of course undermined the left bank, which was composed of comparatively loose materials, for a long. distance. Deprived of its original support, the steeply inclined soil of the commune to the extent of twenty-five hundred acres, including the village of Campo, began to slide downwards in a body. The movement still continues (1875). Many of the houses have been carried off, some overthrown, and the walls of most of the remainder dangerously cracked, Unless costly measures of protection are soon adopted, the whole of this vast moving mass will be washed by the Rovana into the Maggia, and by that river into Lake Maggiore. So insecure is the soil considered at Campo, that as I was lately told on the spot, meadow and pasture grounds, which if safe would be worth 100 dollars (£20) per acre, cannot now be sold for 10 dollars (£2).” In the first part of his work, M. Costa treats of the phenomena of transport of solid materials by running water, and the laws regulating these in different states of the current—from that of a tranquil flow and the first movement of sand and stones through acceleration of the flow, through various degrees of speed, to the deposit of these in consequence of a diminu- tion of this—and having shown that these phenomena include two modes of transport—one appropriately characterized as triage, or selection, bearing onwards lighter or smaller material, while heavier or larger is left, or only rolled along, or dropped, and another in which the whole appears to be borne along ex masse, water and stones and mud commingled, but keeping their relative position while being borne onward—a section is devoted to the discussion of the laws of viscosity, of which this is a form, and of density, as this is effected by immersion in a fluid. An opportunity will afterwards present itself for stating somewhat in detail the phenomena he has observed in connection with the transport of solid materials in both of the modes described. Proceeding, in the second part of his work, to treat of the torrents, he calls attention to two different typical forms of torrential floods—the comparatively limpid floods of the Vosges and the Pyrenees, and the floods of the High Alps, loaded with earth and stones, which they are sweeping along ; and looking upon the former as virtually extinct torrents, to employ the phrase introduced by Surell and now consecrated by use, he confines his remarks to the latter class of torrents, and discusses in connection with them what he considers the essential parts of these—the basin and the deposit. These are treated of at length, and more especially so the geometrical form of the deposit and the laws regulating its increase; also certain remarkable incidental phenomena connected with torrents, and the phenomena attending extinction of torrents. One of the remakable phenomena of which he treats is the bounding of stones before the mountain wave, of which mention hag been made. In regard to this he writes——‘“‘Some of the effects of torrents have appeared so extraordinary that, the law of torrentiality not having been TORRENTS, ETC., BY COSTA DE BASTELICA, 117 ascertained, the imagination set to work to seek out fanciful explanations of what was seen, ; “Thus, for example, has it been with the generally alleged fact, that at the moment of flood large stones set off of themselves, rolling in advance before the current had touched them, under impulse from a current of air preceding the advancing head of waters, “ Kye-witnesses, and these grave men, have affirmed this fact to myself; and M. Surell has collected numerous testimonies of this phenomenon, and has sought to account for it theoretically. In reality, the fact as reported is absolutely impossible. Resistance increases as the square of the velocity. Let a calculation be made, from the velocity necessary to a current of air to displace a stone no larger than an egg; what velocity would require to be imparted to a current of air capable of displacing a stone such as some of those of which this has been told, which must have been at least 50 centi- métres, or 20 inchesin diameter! The thing alleged is physically impossible ; and it must be remarked that the people who allege they have seen those things occur under their eyes, at a few paces from them, do not dream that. if they had been caught in such a current of air they would, at least, have felt it! “When these witnesses are cross-questioned, they all declare that they have seen the stones rolling dry before them ; but no one says he has seen these stones begin to move, These witnesses are trust-worthy, in so far as it is true that the stones were seen rolling before their eyes ; but the point in which they deceive themselves is the explanation of the phenomenon. They have attributed this to the force of the current of air ; there is the mistake. “The fact is a very simple one, and easily explained in accordance with. what has been evolved by the study of the effect of a sudden retardation on a current of matter. Through the velocity acquired, and the upward direction given to their movement, the stones, detaching themselves, are projected forward from the water by which they were borne along. “We find that it is towards the contraction of a water-course, occasioned by a bridge, that the phenomenon manifests itself with most intensity. It is, moreover, at such points that it ought to be most easily observed. At the time of a great flood, there are few spectators in the deserted gorges of the torrents. “From the moment that we are in possession of principles, nothing is more easy than to account rationally for all the effects, and all the accidental incidents which they may produce.” And in a similar way does M. Costa account for other remarkable pheno- mena which have been observed in connectien with torrents. In a third part of the work, M. Costa discusses at great length the extinction of torrents. In his statement of this question, he says,—“ According to the opinion of all the engineers who have had to contend with torrents, with a view to the protection of valleys against their ravages, works simply defensive have been acknowledged to be in most cases, if not useless, at least altogether insufficient, and often dangerous, intensifying at times the evil. “‘M. Surell more especially has put this fact in a clear light ; and he hag established beyond all controversy that it is necessary to carry into the basin the works designed for the protection of the land, that the evil may be attacked at its source. “ He has demonstrated, not less triumphantly, that botsement is the most potent means of extinguishing torrents, as by vegetation we can act, at one 118 LITERATURE ON TORRENTS. and the same time, on the delivery of water, and on the consolidation of the soil. “M, Surell did not confine himself to preaching the reboisement of the mountains, he pointed out at the same time the advantages to be derived from gazonnement, and from small artificial works of consolidation formed of facines properly disposed in the ravines. “ His logical mind perceived the advantages which might be derived from more extensive and costly artificial works, but he did not believe it possible to guarantee their solidity and their durability under the circumstances in which they would be erected. “MM, Scipion Gras et Phillipe Breton have also loudly proclaimed, in a way the most explicit, that the boisement of the valley appeared to them the most efficacious measure which could be adopted against torrents, and that it was only in default of proceedings with a view to extinction being adopted —the application of which, when they wrote, was still surrounded with obscurity and uncertainty—that they proposed the measures they did, as means of diminishing, at least provisionally, the danger. “T do not feel called upon to relate here the difficulties and vicissitudes, moral and administrative, which the foresters had to encounter and over- come in the commencement of the operation. “The alarms of the peasants, in regard to their pastoral interests, were such that they rose in open rebellion. The ferment was extreme in all the mountain regions, more especially in the region of the Alps; and, as always, political passions and local animosities mixed themselves up with the question at issue and envenomed the discussion. “ Now this agitation is almost calmed down, and it is but right to acknow- ledge that this happy result is due in a great measure to the spirit which presided over the direction of the operation. “The means at our command form three categories: bovsement, gazonne- ment, and artificial works of consolidation. In order to determine precisely to what extent, and in what circumstances, each of these means should be adopted, it is necessary to study apart their respective actions, and after- wards resume, in a general discussion of the question, the system to be adopted in a plan of extinction.” And he proceeds accordingly. In speaking of the good done by forests on the face of mountains, forming a basin drained by water-courses, he says their beneficial action is manifold ; and though this manifold action it may be difficult to unfold, the attempt to do this will place, beyond all question that their beneficial action of the water-course is at once most marked and considerable. “Tn the discussions which have taken place on this subject,” says he “the point which has engrossed attention to some extent has been almost exclusively the permeability or impermeability of the soil, and the propor- tion borne by the water absorbed to that which flows off. This is certainly an important question, and no difficulty is found in showing that forests diminish to an enormous extent the amount of water which flows away ; but the service which they render is perhaps greater still in reoulating as Hee do, the flow, and in securing the delivery of only water of perfect uidity. “The study of torrents has shown that the evil done consists not so much in the greater or less volume of water discharged as in the disturbances or perturbations of the flow connected with this. The principal causes of these are sudden changes or variations in the delivery and in the degree of TORRENTS, ETC., BY COSTA DE BASTELICA. 119 fluidity of the flood. And if it be shown that the forests have, in relation to both of these, a regulating power superior to that of any other force operating on the torrent, it will be proved that they are the most potent means of extinguishing torrents. “Tf we could expose, by a vertical section, a wooded slope, it would show in the upper portion a layer of varying thickness, but most frequently of from 30 to 40 centimétres (12 or 15 inches) of humus, in which the fibrous rootlets are so developed that the whole has the appearance of a woolly material. This layer is at once a sponge and a filter. The large roots of the trees penetrate more or less into the subjacent rock. “When the rain falls on ground covered with wood a considerable portion of the water is restored to the atmosphere by evaporation ; another portion is absorbed by the immense expansion of foliage and boughs. If the rain be prolonged the water comes at length to the ground, which again is capable of absorbing an immense quantity. A flow from this is slow to establish itself; it is necessary, first, that the saturation of the sponge- like layer be complete ; and when this is effected—when the water has been able to make a passage for itself by an infinite number of imperceptible channels—the flow, like that of a charged syphon, maintains a certain uniformity of flow, and this it continues for a long time after the rain has ceased. “ So much is this the case that opponents have alleged that forests are more hurtful than beneficial, as they tend to prolong floods. The flood is prolonged, it is true, but the delivery is regulated—diminished at the commencement and increased at the close: the total quantity of water drained away takes a longer time to flow ; it flows during the whole of that longer time; and, what is of more importance, it flows uniformly and equally, with no sudden variations, and thereby much evil is avoided ; and, what is of more importance still, the forest acts at the same time as a filter, delivers no water but what is of perfect fluidity, scarcely even discoloured by the washing away of organic matter, and unable to wash away the earth of the subsoil protected against erosion by its thick covering of humus. “ When, on the contrary, the rain falls on a soil stript of vegetation, it tends to cut this up into ravines, and it does so if the tenacity and resist- ance of the ground be not sufficient to withstand it ; and the flood is subject to great variations in its current, carrying off here and there the earth and other debris of the soil. “Forests have, then, a double action ; on the one hand they consolidate the soil, on the other hand they reduce and regulate the flow of the current —acting at once both on the delivery and on the perturbation,—in other words, on the primary cause and on the secondary causes of the overflowing of water-courses. ; “Tt has been tried to subject to experiment and observation the meteoro- logical and hydrological influences of forests. And doubtless studies so interesting are by no means lost to science. They cannot be too much encouraged ; but it should be borne in mind that they can have compara tively little value in this question, seeing that they cannot take cognizance of this modulating and regulating action. “Tn regard to any flood which we may wish to make the subject of study, it would avail comparatively little to know what quantity of rain falls annually in the basin drained by it. What is necessary to be known is— In what way did the flow of the flood operate during the duration of 120 LITERATURE ON TORRENTS. the flood, taking into account the quantity. of water discharged, and all the causes or sources of perturbation operating ; which is a much more difficult problem. “ And in resolving the whole question into the permeability of the soil, and its capacity of absorption, it appears, importance is attached exclusively to the reduction of the volume of water which flows away. It seems to be forgotten in this that water-courses, if steadily supplied, constitute it may be said the principal riches of a country, and the most potent of all instruments of labour. “ By their modulating power forests act ag vast reservoirs, not only in preventing sudden variations of delivery during a flood, but in feeding the water-courses and raising their level during the period of exhaustion. In what relates specially to the torrents of the Alps, it has been demonstrated that the renewed devastating power which they have exhibited, and which has assumed such portentous magnitude in the course of the last forty years, is a consequence of the disappearance of the woods. When one goes over these lands—cut into ravines and despoiled of all vegetation—he meets with numerous stumps of pine and of larch, which testify that at a period as yet still recent they were covered by vast forests. “M. Surell cites, as an example of the action of forests, the torrent of Savines, now completely extinguished, and the basin of which is everywhere adorned with a magnificent forest of firs and pines. The forest has effectively contributed to the extinction of the torrent, but at this point the following observations may be made : “This natural extinction of the torrent goes back to ages most remote, The cone is of a perfect geometric regularity. At its base, opposite the Durance, it presents a troncature or section, produced by the erosion of the river, and the escarpment of which is about 30 métres (100 feet) in height at its culminating point. This section of the ground lays open the interior of the torrential deposit formed of rolled pebbles. “The whole surface of the cone is cultivated, and on one portion has been built the large village of Savines, the chief place of the canton. “This enormous heap of deposit is situated at the foot of a high mountain called Morgon, in the flanks of which are dug out a profound gorge surrounded by a vast basin, the work of the water. All the upper slopes of the mountain are hung with a beautiful forest, producing firs more than 30 métres (100 feet) in height, and 3 métres (10 feet) in girth. “The lower slopes are deeply ravined, but wooded to the very edge of the thalwegs. A pretty strong stream rises from the principal gorge, but it swells but little ; it carries down no materials, and it flows into the Durance by a bed deeply enclosed in the left bank of the cone. Extinction and stability are complete; but it is certain that if the forest should be made to disappear, anew would disorder revive, and this with the same intensity as before. “In going over the basin with attention, I satisfied myself that every- where the bed of the thalwegs of the gorges and the ravines, formed of the hard rock, were absolutely incapable of being undermined. From this it may be inferred, that during the activity of the torrent, when the basin was being deepened more and more, the surface could not have been wooded. But from the time that the waters had everywhere reached the hard rock, and that these could no more be undermined and washed deeper, their thalwegs in the upper slopes tended to consolidate themselves, taking their TORRENTS, ETC., BY COSTA DE BASTELICA. ‘ 121 natural stable declivity ; and from that time vegetation could begin to take hold and complete the extinction. “This remark is important in this way, that if the disappearance of a forest always gives birth to torrential disturbances, it does not always hold true that one can put a stop to them by the planting of a forest alone. “Much as an unstable ground is protected by being wooded—though it maintains itself and behaves in a hydrological point of view as do the most solid lands, if the wood come to disappear, if the ground be deeply ravined, if the bottom of the ravine continues to be easily undermined and washed away—it becomes extremely difficult to establish vegetation on the moun- tains, which continually crumble away, and which with this instability no longer retain any trace of vegetable soil. “In the Alps there are numerous cases of old mountains which crumble away when the foot of the slope is undermiried by the water. And one is thus left, if he desire to effect a radical and prompt extinction of a torrent, to give, artificially, to the bottom of the ravine a power of resistance to undermining and washing away, by appropriate works of consolidation. “But be this as it may, the potent action of forests is beyond all question. Whatever be the character of the woods—timber forest, coppice-wood, or simple shrubbery—all contribute to give firmness to the soil, to retard and to regulate the flow of the water drained off. “Tn comparing the different kinds of woods, it may be said that lofty timber forests, with their vast apparatus of foliage at a great elevation above the soil, are of most use with a viewto meteorological anid hydrological effects ; and that young trees serve perhaps better to insure the consolidation of the soil on steep declivities. But as generally, on poor land, the soil of timber forests covers itself with branches, &c., it follows that a mixture of the two kinds of woods accomplishes best the end which it is sought to effect.” In regard to gazonnement, he says,— To report efficiently the influence exerted by a bed of turf or herbage covering the soil, it is necessary to follow the very interesting natural process which goes on when pasturing is suppressed on land, till then, given up to the abuse of pasturage. “The facts which I am about to state are not exclusively theoretical, they are confirmed by numerous experiments of enclosures which have been made during a great many years. “T ought first to make an important remark on the subject of the different disintegrations of the soil which occur. Some are simply superficial, and in no way compromise the stability and the solidity of the bulk of the ground. The surface is more or less disintegrated, but the subsoil is unmoved. With others, on the contrary, if they occur on unstable grounds, or on grounds badly poised, breaking up the mass, they tear it deep and move it to its very foundation. “Tt is apparent from what is said that the influence of turf or herbage, even if it could be produced there, can be of almost no effect in this latter case. There is nothing but woods, with their strong and deep roots, which can render firm and protect a soil so unstable, and often on such the wood itself requires the assistance of artificial works of consolidation to sustain it. But the action of turf or herbage is, on the contrary, very powerful if it be employed only to repair a superficial evil by removing traces of erosion. Let us take up, then, the description of the work of nature. “When the soil is no longer trampled, and the few herbs which it is N 122 LITERATURE ON TORRENTS. still, capable of producing are no longer gnawed to the root, there is a real awakening of the forces of nature. All the buried seeds spring to life. From the very first year the ground changes its aspect, it begins to show a green hue. In autumn the plants shed their seeds. From year to year the vegetation spreads and takes possession of the place more and more extensively. ; “In proportion as this change is produced in the state of the surface, the water arrives less rapidly and in less abundance in the ravines and in the hollows of the soil. Its power of carrying off material is weakened ; from the first it has no longer the strength to carry off the larger stones, which roll to the bottom of the ravines and stop there. “To the former work of erosion, and of carrying off material, succeeds the opposite action of colmatage—depositing mud, &c., in its course—and of levelling. This action, at first slow, increases with a rapidly advancing progression. The tendency to effect a general levelling extends throughout the whole section of the ground over which the water flows; and a retarda- tion of swiftness succeeds to acceleration. The vegetation promoted by the fertilizing colmatage takes on an energetic development; it invades more and more the bottom of the ravines. It is there a characteristic sign of victory being assured to the vegetation. “When the upper slope is surmounted by crests formed of crumbling rocks, these summits, more exposed to the destructive action of the elements, continue to produce masses of minute debris, which sustain the action of colmatage on the lower slopes. Ravines, and all depressions of the soil, tend more and more, to efface themselves. The soil goes on rising in these unceasingly. In this new permeable and minutely subdivided layer the turf developes itself with more and yet more vigour, and it finishes by reaching a considerable thickness—it is often 30 centimétres (or 12 inches) thick. One may estimate from this the influence produced by the thick layer of turf or herbage. “Tn regard to the consolidation of the soil, the protection is complete. “In regard to hydrology, the absorption of the water by this permeable layer is so much the greater as—be it in consequence of a greater levelling of the surface, or be it through the effect of the long herbage—the flow of it is subjected to a very great retardation. “The levelling, in extending indefinitely the section, reduces the mass of water to an extremely thin sheet ; and then each shoot of herbage easily breaks this sheet, so that the water which can only acquire velocity by a certain concentration is broken up to such a degree that all flow is impossible, excepting in some extraordinary case as when a water-spout breaks and pours out itself on a single point. “Woods also induce colmatage on the higher slopes which they occupy when the crests are denuded and formed of crumbling rocks, throwing off not only fine debris, but also very often stones and large pieces of rock, “Tn certain forests all the trees are severely grazed on the upper side by the shock of stones which roll from the upper part of the mountain. When these projectiles are launched with very great velocity they roll to the foot of the mountain; but most frequently they stop on the lower slope, and form, by their accumulation, a layer of variable thickness, “When the colmatage acts slowly and regularly it is extremely favourable to the vegetation. It is then one of the causes of the beauty of the woods on the upper slopes. TORRENTS, ETC., BY COSTA DE BASTELIOA. 123 “In a perfected forest culture it would be possible, by light works, to enrich the soil by favouring this natural colmatage on steep lower declivities, and if it be desired to fix voluminous materials, wood is preferable ; but on gentle slopes the turf and herbage, which act on the small gravel and the finest sands, secure a colmatage more complete and more compact. “Tt is a fact, ascertained by experience, that lands so covered are more equably levelled than are wooded lands. “One may then draw this consequence—that, in the given cases, even for lands which it is desired to cover with woods, it is often preferable to subject them previously to the treatment of simple enclosures, that they may be subjected to this natural preparation which levels and fertilizes them. “When, in consequence of the bad state of the soil, and the too advanced state of the ravine, action of this kind would be too slow to heal over these deep sores, it is necessary to aid them by artificial appliances. It often suffices to put some facines across the ravines, to induce the process of colmatage, and to give to this great energy. It is impossible on this point to lay down any fixed rule. The principle is this—when it is by its concentra- tion that the water acquires its velocity, and its power of destruction, it is necessary, a8 much as possible, and at all points, to diminish the velocity by extending the section. “Simple enclosure does not produce everywhere a pure gazonnement ; there is required a certain altitude favourable to the turf forming plants of high mountains, and also certain conditions of the soil. In the lower districts of some countries, from the time that a piece of ground is no longer open to flocks and herds, vegetation revives, and all the plants of the locality, the seeds of which have been preserved in the soil, or have been borne thither by the wind, develope themselves. These are the lavender, the broom, the fescue grass, and very often forest trees, especially the oak, the seeds of which are very tenacious of vitality. ‘All this natural vegetation, whatever it may be, is valuable when it acts to restore an impoverished land, and to combat the redoubtable effects of ravines. “Tn conclusion, vegetation, under all its forms, is the most powerful means of the restoration and consolidation of the soil, and through this also the most active and most valuable agent in the extinction of torrents; but there are certain cases in which the evil has made such fearful progress that nature, left to its own powers, would be powerless to repair it. It is absolutely necessary to come to its aid if we wish to protect the valley effectually, and above all if we wish to do it quickly.” Referring to the use of barrages advocated by Surell, by Scipion ‘Gras, and by Philippe Breton, M. Costa discusses the whole theory of such appliances, viewed both as designed for the consolidation of the soil in danger of being washed away, and as designed to retain or collect gravel— the former the purpose for which they were proposed by M. Surell, the latter the purpose for which they aré prescribed by MM. Gras and Breton. He discusses both at considerable length, and also the diversion of torrenty into new courses, and what combinations of each and of all of them with reboisement and gazonnement were likely to be most efficient in different circumstances; and in illustration of the success in consolidating ground which had followed proceedings such as he advocates, he cites what had been accomplished in the extinction of the torrent of Saint-Martha, near .124 LITERATURE ON TORRENTS. Embrun, to which I shall afterwards have occasion to refer ; and he proceeds in the next division of the work to the consideration of the torrential phenomena in great rivers. He says, that with the knowledge which has been attained in regard to mountain torrents by observation and experience, the question, How can they be controlled and stifled? may be considered as settled. But the game cannot be affirmed in regard to rivers, which throughout their course are governed by the same laws—both those governing or regulating the flow of water and those governing or regulating the torrential phenomena— any apparent modification being attributable to the greater quantity of water, its greater fluidity or lesser viscosity, the lesser rapidity’ of its flow, and to the more extended reaches throughout which this maintains a uniformity. All that has been done hitherto in regard to rivers has related to the delivery or quantity of water in flow. Attention has not been given to the perturbations of torrentiality and to effects produced by these. Tn the regulation of river currents it is desireable that the delivery or water in flow should be equalized, and all perturbation in that flow reduced as much as possible; and he says,—“ This double result is obtained by the reboisement of the mountains, but it may be brought about in two different ways. When the object to be accomplished by the planting of forests is to equalize the delivery or quantity of water it is necessary to extend the boisement over extensive areas, comprising the greater portion of the basin. Tf, on the other hand, it is the perturbations in the flow upon which it is desired to act, it is necessary to concentrate the reboisement on properly selected points, and, it may be, to strengthen the action of these by a series of the artificial accessory works employed for the extinction of torrents. “It is this latter system which is alone efficacious and practicable in acting on a great water-course. “Tn a basin such as that of the Loire, for example, there might be planted a hundred thousand hectares of land without perceptibly modifying the régime of the river, if the lands were not selected with intelligence with a view to the consolidation of the soil and to the accomplishment of the end desired. A study of the whole course of the river, and a comprehensive plan of operations founded thereon, is absolutely requisite as a preliminary measure, “It is necessary from the first thoroughly to know the régime of the parti- cular water-course, and to ascertain its torrentiality. This may be accom- plished by a general reconnoissance. * All the affluents should be classified in a hydrological chart, according to their degree of torrentiality. “ Most frequently an inspection of the state of the confluence suffices to reveal the régume of the affluent. When such is torrential it will be found to straggle over an extended bed before flowing into the main stream. “ By subjecting, then, every one of the affluents to such an examination, and following out this in all the upper ramifications of the river, it is casy to determine what are the main centres of production of the stone or clay materials borne along by the river, which are the causes of the perturbation which have to be fought. “By this procedure the evil is localized, determined, and circumscribed ; and it is often astonishing to find how limited in extent, compared with the area of the basin, are the whole of the sources whence the gravel is obtained. “By such a procedure the operation is not left to chance, All is done a TORRENTS, ETC., BY COSTA DE BASTELICA. 125 rationally, with an adaptation of means to the end. From the time that the extent of the sore which has to be cicatrized is known and defined, it is easy to report beforehand on the importance of the work to be done, on the expense it will entail, and on the time which will be required for its execution. é “Tt may be necessary to limit the operations to bring them within the means at command, but what is done is done in accordance with a fixed plan and with the assurance of success. “T do not conceal from myself that I expose my remarks to the charge of being premature, I state them more for the future than for the present. A work so colossal cannot be improvised. Every new idea requires to be matured before it be accepted. It has got, when true, to pass through the sieve of contradiction and opposition, but it issues in triumph. “The reboisement of the mountains, looked at from this point of view, has already overcome obstacles ; and it has stood the test of public calamities. It is making good its position day by day, and in proportion as it becomes better understood, more and more will the necessity of developing it be felt. “To state my opinion in a few words, this is the necessary solution of the matter : it is an efficacious one, and there exists not another for a problem which we cannot elude, and which presents itself in a more and more threatening aspect. “T shall esteem myself happy if by this treatise, which is imperfect, but which is expressive of deep convictions, I may contribute to hasten on the time when our beautiful rivers shall no longer inspire dread or bring danger, but become magnificent highways of navigation.” The title of the work of M. Costa bears that he treats not only of the laws, causes, effects, and means of repressing torrents, but also of the means of utilising them. Means of doing this are indicated again and again in the course of the work, but the suggestions thus given exhaust not his views of what may in this way be effected. “The great perturbations in the order of nature which leave often behind them saddening traces of their occurrence,” says he, ‘fulfil, nevertheless, a useful, and it may be a necessary, function in the work of creation: The storms which create a turmoil in the atmosphere purify the air. Without the cyclones of the Indian Ocean, the latitudes in which they occur,would not be habitable. And storms on the sea help to prevent a tainting of the waters, by commingling with the superficial layers waters from deeper layers more nearly saturated with salt. “The inundations of water-courses, against which we seek to protect ourselves now, have served to create fertile alluvia on gigantic deltas, and on many rich valleys, some of them the most beautiful parts of the earth, in which human society has been able to develope itself, and to bring forth its marvels. “ Even in our own times, beneficent inundations—natural or artificial— by depositing in certain valleys an earth which is repairing an exhausted land, are the means of generating wealth. We have, then, in inundations a force or power which sometimes occasions ruin and devastation, but which sometimes becomes a valuable instrument of good, according as its action may be chaotic or controlled. _ “ Having seen how this force may be controlled and kept within bounds, it is reasonable to suppose, and I cannot but believe the supposition to be in 126 LITERATURE ON TORRENTS. accordance with fact, that in accordance with that unity which pervades every thing, it is possible to indicate a way by which it may be utilised ; and this all the more tHat such a way there is, based on the very laws regulating torrential phenomena which have been brought under consideration. “Itisthis consideration which has determined me to devote some pages to that interesting agricultural operation known under the name of colmatage, or warping, and practised by the Egyptians from time immemorial with great skill. : “To transform deserts into meadows—stony ground, absolutely sterile, or producing only a sorry pasturage, into alluvial lands, capable of bearing a covering of the most luxuriant and richest vegetation—is certainly not only one of the most lucrative enterprises, but also one, in every aspect of it, most interesting. Everywhere, where it is has been tried in favourable circum- stances, it has produced results surpassing all expectations which had been entertained. “There exist in France extensive districts, especially in the south, in which this operation might be carried out advantageously. “The immense plain which extends from the town of Arles, in Provence, to the sea on the left bank of the Rhone, known under the name of the Craw, is in its central part a veritable desert of forty thousand hectares, covered with pebbles, thoroughly burned up by drought in summer, but where, during the rainy season in winter, there grow some stalks of herbage on which the flocks of transhumant sheep feed. “The fertilization of this plain by colmatage, by means of the waters of the Durance, would be of immense benefit not only to Provence but to the whole country. It would be there a creation of enormous agricultural wealth, which would, without fail, have a reaction on the national wealth and the general well being.” He statesthat the credit of first entertaining this idea doesnot belong to him ; that it has again and again engaged the attention of men given to the study of natural phenomena, and of great ameliorations of which terrestrial condi- tions are susceptible ; and he gives great credit more especially to M. Scipion Gras for what he had done and was doing to promote the enterprise. Having done so, he proceeds to expound his views of what might be effected. Next in importance to preventing the devastations occasioned by inunda- tions, by the washing away of earth and earthy materials from the higher- lying basins drained by torrents, and by the deposit by these on fertile fields and valuable lands of a covering of sand and eravel and stones, the detritus of mountains washed away by the torrent in its rave, he seems to have deemed the plan of so constructing water-courses that, where practical or desirable, these should be made to make some compensation for the mischief done by them, or by others of their kind, by covering barren plains with fertile soil. As the result of the study of natural phenomena, he states, that on pure clay a gazonnement of herbage is not produced, but that it developes itself with great vigour on miscellaneous deposits, and this gives rise to the speedy formation of an upper layer of veyetable soil, and that thus, in a very short time, there is produced there fertile grounds requiring only in addition a little manure to promote their fertility. Leaving the subject of: torrents, except in so far as their phenomena might TORRENTS, ETC., BY COSTA DE BASTELICA. 127 serve to illustrate his subject, he prepares for the discussion of the possi- bility of preventing inundations by a discussion of the torrential phenomena in great rivers. And considering, as he did, that attention had been given too exclusively to variations in the delivery of water-courses—no previous writer, so far as was known to him, having even admitted the idea of per- turbations in the flow giving rise to a confusion of the so-called hydraulic laws, of something like a revolution breaking out in a water-course and producing an instability which mocked all provisions and precautionary measures alike—to these perturbations and their phenomena he gives special attention ; and he again brings under consideration what it is which consti- tutes torrentiality, with a view to showing that it is seen in rivers as well as in what are designated torrents. According to M. Costa, his definition of a torrent embodies the idea of its bearing along earthy matter in suspension ; and he states that it does so both in a mass and in what is known in France as triage, dropping some and carrying on others of the materials in question ; in the former case all the rocks, pebbles, and lesser fragments are carried along in something like their relative positions, as would be the case in a viscid mass or in a glacier ; in the latter the weightier materials are dropped first, and this going on more or less continuously, the matters in a state of extreme comminution are carried furthest. The difference in mode of transport appears in connection with difference in the velocity of the flow. When this is so great as to bear the whole along in a mass, the stones, whatever their size, do not come into collision, and if any were withdrawn they would be found to be as little rounded as are the stones falling from a glacier and forming a moraine. But when the velocity is being impaired, as this goes on the stenes begin to roll, suspended in the water, and they may come into collision one with another ; and the heavier sinking, these are for a time rolled along the bottom and subjected to collision and friction. At length they rest, and where they rest the collision of others following and proceeding further subjects them to continued abrasion ; and what happens thus to the heavier masses happens there or further in advance, in succession as the velocity is reduced, to others of lesser weight. In view of these phenomena he makes valuable suggestions in regard to | the structure of barrages. He suggests that by submerged barrages of little height, if these be properly disposed, the velocity of a torrent might be so reduced as to secure a deposit over a great extent of ground of the impal- pable mud borne down by a torrent. He states that much of the mud thus carried along would be infertile, but that much fertile vegetable mould is thus buried in the sea; and he proposes that in certain circumstances in which this may be practicable and desirable this should be so secured ; he points out places of great extent in regard to which he proposes that this should be done; and he cites what has been effected in the High Alps in ‘evidence of the practicability and advantages of the measure. M. Costa looks, in the light of these observations, at the geological phenomena which led M. Cézanne to conclude that the so-called glacial or drift periol was succeeded by what he considered a torrential era; the different appearance of stones founc in some heaps from that presented by these in others—these being in the one angular and in the other rounded, the former like the stones forming moraines deposited by glaciers, the others like those found in ls de déjection, and attributable to attrition, 128 LITERATURE ON TORRENS. escaped in those, having befallen these, having been suggested or been called in to support the theory or hypothesis. M. Costa, looking to the terrential phenomenon of transport of material en masse, differs from M. Cézanne only, or chiefly, so far as to attribute the whole, or by far the greater part of the deposits in question, which are extensively distributed over some parts of France, to torrential action alone ; maintaining and citing in support of his views phenomena of torrents established by his previous observations which go to prove that torrential action is equal to the production of all the phenomena of these deposits,—the transfer of the blocks of the greatest magnitude seen, and the transfer of these and of lesscr stones without damage to their angular outlines, and to the deposit of them where they are, and in the form in which they are found. He does not deny that the effect of glaciers is what it is believed to be, but he alleges that torrents, charged and surcharged with earthy matter, bear off rocks and stones, and such earthy matters, in certain circumstances, in a somewhat viscid mass, in which each constituent part may be con- ceived of as retaining its relative position very much as such matters do in a glacier, and therefore with their angularities unbroken. But in regard to the composition and contour of the beds of deposit, he cites observations of M. Cézanne and of his own which seem fully to warrant a conclusion drawn by him from them, that all moraines—deposits chiefly associated with glaciers—have not been produced by these, some having been pro- duced by landslips and avalanches, if not otherwise, but that all cones of dejection are the products of torrents. But he goes further, alleging that while the melting or breaking up of the ice is only an accidental and local phenomena, torrential phenomena are common and universal, and are so to such an extent as to make the term torrential era objectionable ; torrential force being a force which not only has manifested itself in a permanent and continuous manner within and throughout the historic period, in modern alluvia, and in the geologic period, in ancient alluvia—buried, some of them, to the greatest depth ; but also in what may be called the cosmogonic period, at every instant of the carth’s life exercising an influence on the very contour of the globe, if not also acting in the sun and in the planets. Such are the views entertained by M. Costa of such deposits as arc described in my citations from the work of M. Cézanne, And with all his enlarged and comprehensive views of torrential action, he appears to have held the same views as those I have cited as the views of Marschand and of Cézanne in regard to the later history of torrents in France, to the extinction of these by the spread of vegetation, to the resusci- tation of them by the destruction of forests, and to the re-cxtinction of them by reboisement and gazonnement, Thus do all concur in pointing out to us the stage of the process in South Africa, and in other newly settled countries, indicated by torrential floods, when looked at in connection with the destruction of grass and herbage and bush and trees witnessed in and beyond the portions colonized by Europeans. In regard to the means to be employed to secure the extinction of these, he says,—‘‘ When the torrentiality is feeble, and the evil consists mainly in the quantity of the water, it is by buisement, and the spread of vegetation, that it should be sought to effect the restraint or extinction of it. If, on the contrary, the torrentiality is extreme, and the devastations produced by it proceed principally from the perturbations in the flow being now TITLES OF TREATISES. : 129 violent, now feeble, this should be rectified by the extensive application’ of works of consolidation, such as Surell has recommended. “The works of reboisement and gazonnement, to be effectual, require to be extended over large areas. Works of artificial consolidation, on the contrary, may be confined within a limited space, and the evil may in some cases be stifled by attacking it in its principal source. “Sometimes it may happen that, through the pastoral and agricultural operations carried on, it is impracticable’ to’ give to boisement’ the whole extension necessary to meet the evil. Every case must be decided on its own merits. And, from the general considerations adduced, it is apparent that it is impossible to lay down invariable rules of procedure applicable to every case. “ When there is no special urgency for securing immediate results, it is preferable to employ at once vegetation. ‘By enclosing a'space, it is found that the spontaneous work of nature exercises a most favourable influence on the soil. Cover, then, with woods all the lower slopes, where there is no fear of the earth crumbling away,’and where the spontaneous’ wotk of nature is not likely to cover them with vegetation. With this done, the delivery of water will insensibly diminish ; losing bulk and velocity, it retains no longer the same power of undermining and washing away; the hills are less frequently and less powerfully attacked ;'arid where it is reckoned that the torrent is sufficiently enfeebled, there may then, if it be thought necessary, be established in the gorges, with greater ease and at less expense, works of consolidation deemed useful. “This order of procedure is more sure, and more economical, but more slow than is the reverse. “ With the vegetation there may be combined, on the upper slopes and in the lesser ravines, a great many small works of consolidation, the design of which is to effect this by retarding: the velocity of the flow, and the sub- stituting of colmatage for the undermining and carrying away of the soil. “The time for undertaking works of consolidation in the gorges must be determined by the degree of urgency for a speedy extinction of the torrents, and by administrative considerations, of which the superior authority’ is the judge.” In illustration of what may be done, M. Costa cites the extinction of the torrent of Saint Martha, already referred to. Besides the works which have been cited, the following have been published in France :— Beteranp, membre de I’Institut, inspecteur général des ponts et chaussées. Hydrologie et météorologie du bassin de la Seine. BELANCER, ingénieur en chef des ponts et chaussées. Hssaz sur le mouve- ment permanent des eaux cowrantes, Cotzienon, cours d’hydraulique professé 4 I’Ecole des ponts et chaussées, Comoy, inspect. gén. des ponts et. chaussées. émoures sur les owvrages de défense contre les inondations. Darcy et Bazin. Recherches hydrauliques. Premiere Partie—Recherches expérimentales sur l’écoulement de l’eau dans les canaux découverts. Deuxitme Partie—Recherches expérimentales sur la propagation des ondes. Dumont, ingénieur en chef des ponts et chausstes. Les eaua de Lyon et de Paris,—projets, tracés et détails d’exécution suivis d’une pratique des distributions d’eau, ce) 130 LITERATURE ON TORRENTS. Durvir, inspect. gén. des ponts et chaussées. Des Inondations, examen des moyens proposés pour en prévenir le retour. Durvit, inspect. gén. des ponts et chaussées. Etudes pratiques et théoriques sur le mouvement des eaux courantes, suivies de considérations relatives au régime des grandes eaux, au débouché a leur donner, et a la marche des alluvions dans les riviéres & fond mobile. Faravg, ingénieur des ponts et chaussées. tude sur la corrélation entre la configuration du lit et la profondeur dean. Fournii (V.), ingénieur des ponts et chaussées. Résumé des expériences hydrauliques exécutées par le gouvernement américain sur le Mississipi, et remarques sur les conséquences qui en découlent relativement a la théorie des eaux courantes. ——, ingénieur des ponts et chaussées. Progrés récents de la météorologie. , Amelioration des riviéres torrentielles, GraezrF, inspect. gén. des ponts et chaussées. Théorie des réservoirs. Krantz, ingénieur en chef des ponts et chaussées. urs de réservoirs, Lamarressn, Hydrologie du département du Jura. Matizreux, ingénieur des ponts et chaussées, professeur 4 I’Ecole des ponts et chaussées. apport sur un voyage aux Etats-Unis extcuté par ordre de 8. Buc. le ministre des travaux publics, Mancon, ingénieur en chef des ponts et chaussées, professeur 4 l’Ecole des ponts et chaussées. Instructions pratiques sur le drainage. , Experiences sur Vemploi des eaux dans les irrigations, Mowestier-Savienat, ingén. des ponts et chausstes. tudes sur les phénoménes, Vaménagement et la léguslation des eaua au pont de vue des inondations, avec application au bassin de VAllier, riviére & régime torrentiel, affiuent de la Lowe. Napavtt pp Burron, ingénieur en chef des ponts et chaussées, professeur 4 YEcole des ponts et chaussées. Des submersions fertilisantes, colmatage, limonage, irrigations d’hiver. , Des irrigations, canaux darrosage de U Italie septentrionale, Partior, ingénieur des ponts et chaussées. tude sur le mouvement des marées dans les parties maritimes des fleuves. De Passy, ingénieur en chef des ponts et chaussées. tudes sur le service hydraulique. Poca, ingénieur des ponts et chaussées. Htude des cowrants et de la marche des alluvions aux abords du détroit du Pas-de-Calais. Ports (M. A.), inspect. gén. des ponts et chaussées (en retraite). Qzel- ques mots de réponse & la brochure de M. Dupuit, intitulée: des Lnondations. Vigan. Irrigations des Pyrénées orientales et phénomeéne dit : Production des eaux. Several of the subjects embraced in this department of the forest science of France have engaged the attention of students of nature in other countries. Copious extracts from French works, with copies of official documents issued in France relative to reboisement and gazonnement, are embodied in an official report, issued in the province of Luxemburg, entitled Dee Reborsement des Terraines vagues Rapport présenté au Conseil provincial par la Députation permanente Session de 1867, But being a compilation and report, made with a view to work being undertaken, it communicates no accounts of hydrological results obtained, CEZANNE ON THE HARTZ. 131 Streffleur, in a paper, Ueber die Natur und die Wirkungen der Wildbiiche, which first appeared in the Ber, der Ul. N. W. Classe der Kaiserl. Akad. der Wiss. for February 1852, maintains that all the observations and specula- tions of French authors on the nature of torrents had been anticipated by Austrian writers ; and in support of this assertion he refers to the works of Franz von Zallinger, 1778, Von Arretin, 1808, Franz Duile, 1826,—all published at Innsbruck,—and Hagen’s Beschreibung neuerer Wasserbauwerke, published in Konigsberg in 1826. And M. Cézanne, in his continuation of the treatise of M. Surell, says, and says unhesitatingly, after speaking of the importance of utilizing, taming, and domesticating torrents,—as beasts and birds have been tamed, domesticated, and utilized,—% France and Switzerland are not the only countries in which the struggle against devastating running waters is being carried on with alternate triumphs and defeats. And we may conclude from the works now analyzed, and from the numerous publications which there are of the same kind, that the time is still remote when man shall have completely subdued, and, if the word may be used, domesticated, tamed, and utilized the wild waters of the mountains. But there is one happy land, the picture of which, contrasting with these gloomy sketches, may be offered to inquirers as a model and as an encouragement. It is the German Hartz. “This mountainous mass, almost isolated on all sides, and but lately divided amongst four Governments, raises its highest summit—the Brocken—to a height of 1250 métres, upwards of 4000 feet; steep slopes and deep thalwegs are not awanting, nor are abundant rains—the rainfall ranging from 600 to 1500 millimetres (from 24 to 60 inches). The ground is very diversified ; granitic eruptions have dislocated schists of all kinds ; all circumstances and conditions favourable to torrential phenomena are there in combination 5 but the mining industry, in quest of motive power, has seized upon the water—a force supplied without money and without price, and renewed unceasingly by nature ; and it may be said that there there is not a single drop left to follow its natural course ; from the highest slopes the rain is collected in furrows forming gutters; all the ravines are closed up, and numerous ponds store up their supplies ; collected in canals the waters make the circuit of the brows of the hills, are carried across valleys, b themselves in projecting spurs, and, conducted to the gate of the factories, move the hydraulic wheels placed one below another at all the descending levels of the mountains ; and, coming at length to the thalweg, the waters are not yet freed,—they are made to descend into the mine and there to work underground. “Seventy ponds or reservoirs of the Ober Hartz have an area of 240 hectares ; they store up fifteen millions of cubic métres, which put in move- ment above ground 180 water-wheels, and underground 23 wheels and 2 hydraulic presses.” From the report of MM. Belgrand and Lemoine, in the Annales des Ponts et Haux, for 1868 (II. p. 307), it appears,— There are in all 200 kilométres (upwards of 150 miles) of canals employed to bring the waters to the ponds, and to lead them to the manufactories and to the mines. “From the highest situated pond (Hirschler Teich) to the Lautenthal, there is for wheels above ground a total fall of 292 métres(well-nigh 1000 feet), “ For the mines the available fall is still greater ; it is about 370 métres (nearly 1250 feet). These waters underground give motion to draining pumps and other machinery, are re-united in different galleries or tunnelsa— 132, LITERATURE ON TORRENTS. finally in the Ernst-August-Stollen—situated at about 370 metres (1250 feet) under the plateau of Chausthal. This canal, in which are collected all the waters of the subterranean sheets, conveys them to the open air at Gittelde ; it is not less than 23-600 métres in length, and its other dimen- sions are considerable, for this long subterranean passage can be made by boat. Its breadth is 1-90 métre (6 feet 4 inches), and its height 2°70 (or 9 féet), This magnificent work was completed in 1864, and cost a little more than three millions of francs.” M. Cézanne goes on to say,—“‘ Many of these works date from the begin- ning of the eighteenth century. It is a hundred and fifty years.since the inhabitants of the German Hartz have subdued, tamed, and turned to use their running waters; it is only ten years since we began to give ourselves to the attacking and mastering of the torrents of the Alps!” In the German literature of Forst-Kunde are not a few treatises on torrents, on their destructive effects, and on the means of preventing and counteracting these. Streffleur refers to a brochure by Franz Duile. Jt was published in 1826, under. the title Ueber Verbaunung der Wildbiche in Gebirgs Lindern, and in it the author gives an exposition of the principles which should be applied to all works of this kind. “ He studied successively,” says Marschand, “the construction of stone dams and of wooden erections having the same object to accomplish. The former, described by him, are dry-stone dykes, and are composed of a horizontal vault with the arch directed up the stream, and sustaining walls forming kinds of butments where the hills are not of rock, and to prevent underminings a radier or screen of stone retained by wood-work. The summit of the dam is lowered somewhat in the middle to facilitate the flow of water, and it is covered with a wooden plank designed to maintain the solidity of the summit. The wooden barrages described by him are similar to those in use in many parts of the French Alps. “‘ Duile superintended numerous works on torrents, but through neglect, or perhaps through the force of the current, they all crumbled into ruins ; and.at the close of his life he expressed to Professor Culmann regret that he had undertaken works against torrents. “He treated also of reboisement, assisted by clayonnages or hurdles, and, in a word, of everything relating to the extinction of torrents, “ Great works undertaken by his advice leave no doubt of the efficacy of his system.” In 1844 was published at Darmstadt Das Verdriingen der Laub-Wélder, in Nordlichen Deutschlande durch die Fichte und der Keifer, by Edmond von Berg. In 1852 was published at Erlangen Das Verhalten der Wald- baume gegen Licht und Schatten, by Gustav Heyer; both of which have reference to the subject under consideration. In a Handbuch der Physischer Geographie by Kléden, referred to by Marsh, it is stated by the latter that the author, “admitting that the rivers Oder and Elbe have diminished in quantity of water—the former since 1778, the latter since 1828—denies that the diminution of volume is to be ascribed to a decrease of precipitation in consequence of the felling of the forests ; and states, what other physicists confirm, that during the same period meteorological records, in various parts of Europe, show rather an augment- ation than a reduction of rain.” GERMAN AND ITALIAN LITERATURE. 133 The statement made by Kléden is in accordance. with observations made by others elsewhere. The effect of forests, and of the destruction of forests, on climate, both as regards the water supply and the temperature, has received great attention from Dr Draper, Director of the Meteorological Observatory in the Central Park, New York, with results, to some extent, in accordance with those stated, deduced from observations in the United States of America. I have not seen the statement made by Kléden, which occurs in his Handbuch der Physischer Geographie (p. 658), but taking the import of it to be as given by Mr Marsh, the phenomena may be susceptible of explanation. There may have been a general increase of the rainfall, but a diminution of the drainage of the surplus moisture of the land. The ground may have become more desiccated, and that to such an extent that even an increased rainfall does not maintain the rivers at their height. Of other German works bearing on the subject of torrents I may mention the following :—Die Ocesterreichischen Alpenlindar und thre Forste, by Joseph Wessely—published in Vienna, 1853. Ansiehten uber die Bewaldung der Steppen des Europeschen Russland, by J. Van den Brinken—Braunschweig, 1854. Die Gebirgsbache und ihre Verherungen, by Franz Muller—Landshut, 1857 ; the author was a Bavarian engineer, and the work treats of the con- struction of barrages, more especially those of masonry and wood, but it treats also of the fixation of mountains, by means of hurdles, with a view to reboisement. Der Wald samt dessen wichtigen Einfluss auf der Klimat, dc. —published in Vienna, 1860. Die Alpen in Natur und Lebensbildern, by H. Berlepsch—Leipsig, 1862 ; a work of which an English translation, by Stephens, has been published. In Italy much attention has has been given to irrigation, and the utiliza- tion and economising of the water supply; the Italian literature on subjects connected therewith is very voluminous; and the effect of vegeta- tion on the humidity of the climate, and the supply of moisture for the promotion of vegetation, has not been overlooked. Of Italian works relating thereto the following may be noted :—Dell’ Immediata Influenza delle Silve sul Corso delle Aeque, by Castellani—Torino, 1818-1819. Dell’ Impiante.¢ Conservazione dei Boschi, by Guisippe Cereni—Milano, 1844. Mecessita det Boschi nella Lombardia, by Antonio Giovanni Batti Villa—Milano, 1850. Connisulla Importanza e Coltura die Boschi, by Pietro Caimi—Milano, 1857. Le Condiziont de Boschi de fiumi e de Torrenti nella Provincia de Bergamo, by G. Rosa, in Politecno, Decembre, 1861, pp. 606-621. Studit sui Bosche, by the same writer, in Politecno, Maggie, 1862, pp. 232-238. The subjects of colmatage or warping, alluvian drainage, and defences against inundation—all of which come within the scope of the French treatises I have cited—have also found a place in the Italian literature of hydrology. To this chapter belong the following works :—Memorie sul bonificamento delle Maremme Toscano, by Fernando Tartini ; Sulle Paludint Pontine, by Eustachio Zanotti; Relazione e voto sopra a deseccamento delle Paludi Pontine, by Gaetano Rappini ; Sopra la distribuzione delle alluvione, by Vittoria Fossombroni; Richerche idrauliche relative alle Colmate, by Pietro Paoli; Itorno al ripararo delle innondazioni dell’ Adige la. citta di Verona, by Antonio Lorgna. ; In our own language has appeared in a first edition, entitled Man and ' Nature, published in 1863, and in a second edition, entitled The Earth. as modified by Human Action, published in 1874, by the Hon. George P. Marsh, 434 LITERATURE ON TORRENS, Minister of the United States of America at Rome,—a work in which there is embodied a great mass of valuable information on the subject of torrents, or the extiriction of these, and on subjects closely related to these. J shall afterwards have occasion to quote at length statements by Mr Marsh in regard to the provinces of Dauphiny and Provence, to the valley of the Rhone, and to the department of Dévoluy. His own remarks on subjects connected with the occasion, phenomena, and control of torrents are not less deserving of consideration. His position as Minister of the United States at different courts, with a perception of the importance of such matters, have given him exceptional advantages for the study of this matter, as of much besides, of which he has conscientiously availed himself, and embodied the results in his more comprehensive treatise. By the information supplied by such works as Les Inondations en France depuis le Vie Stécle jusqw’a nos jours, by Champion, and Les Foréts de la Gaule et d Vancient France, already cited, the student in this department of forest science can carry back his studies to times that are past. Of these Mr Marsh writes:—“ The remarkable historical notices of inundations in France in the Middle Ages collected by Champion are con- sidered by many as furnishing proof that, when that country was much more generally covered with wood than it now is, destructive inundations of the French rivers were not less frequent than they are in modern days. But this evidence is subject to this among other objections : we know, it is true, that the forests of certain departments of France were anciently much more extensive than at the present day ; but we know also that in many portions of that country the soil has been bared of its forests, and then, in consequence of the depopulation of great provinces, left to reclothe itself spontaneously with trees, many times during the historic period ; and our acquaintance with the forest topography of ancient Gaul or of medieval France is neither sufficiently extensive nor sufficiently minute to permit us to say with certainty that the sources of this or that particular river were more or less sheltered by wood at any given time, ancient or medieval, than at present. I say the sources of the rivers, because the floods of great rivers are occasioned by heavy rains and snows which fall in the more elevated regions around the primal springs, and not by precipitation in the main valleys or on the plains bordering on the lower course. “‘ The destructive effects of inundations, considered simply as a mechanical power by which life is endangered, crops destroyed, and the artificial constructions of man overthrown, are very terrible. Thus far, however, the flood is a temporary and by no means irreparable evil, for if its ravages end here, the prolific powers of nature and the industry of man soon restore what had been lost, and the face of the earth no longer shows traces of the deluge that had overwhelmed it. Inundations have even their compensa- tions. The structures they destroy are replaced by better and more secure erections, and if they sweep off a crop of corn, they not unfrequently leave behind them, as they subside, a fertilizing deposit which enriches the exhausted field for a succession of seasons. If, then, the too rapid flow of the surface-waters occasioned no other evil than to produce, once in ten years upon the average, an inundation which should destroy the harvest of the low grounds along the rivers, the damage would be too inconsiderable, and of too transitory a character, to warrant the inconveniences and the expense involved in the measures which the most competent judges in many parts of Europe believe the respective governments ought to take to obviate it, MARSH ON TORRENTS, 135 “ But the great, the irreparable, the appalling mischiefs which have already resulted, and which threaten to ensue on a still more extensive scale here- after, from too rapid superficial drainage, are of a properly geographical, we may almost say geological, character, and consist principally in erosion, displacement, and transportation of the superficial strata, vegetable and mineral—of the integuments, so to speak, with which nature has clothed the skeleton frame-work of the globe. It is difficult to convey by descrip- tion an idea of the desolation of the regions most exposed to the ravages of torrent and of flood ; and the thousands who, in those days of swift travel, are whirled by steam near or even through the theatres of these calamities, have but rare and imperfect opportunities of observing the destructive causes in action, Still more rarely can they compare the past with the actual condition of the provinces in question, and trace the progess of their conversion from forest-crowned hills, luxuriant pasture grounds, and abun- dant cornfields and vineyards well watered by springs and fertilizing rivulets, to bald mountain ridges, rocky declivities, and steep earth-banks furrowed by deep ravines, with beds now dry, now filled by torrents of fluid mud and gravel hurrying down to spread themselves over the plain, and dooming to everlasting barrenness the once productive fields. In surveying such scenes, it is difficult to resist the impression that nature pronounced a primal curse of perpetual sterility and desolation upon these sublime but fearful wastes, difficult to believe that they were once, and but for the folly of man might still be, blessed with all the natural advantages which Providence has bestowed upon the most favoured climes. But the historical evidence is conclusive as to the destructive changes occasioned by the agency of man upon the flanks of the Alps, the Apennines, the Pyrenees, and other mountain ranges in Central and Southern Europe, and the progress of physical deterioration has been so rapid that, in some localities, a single generation has witnessed the beginning and the end of the melan- choly revolution.” He cites statements made by Surell and by Blanqui which have been already quoted. He says, in connection with their statements relative to Dévoluy, Barcelonette, and Embrun,—“ It deserves to be specially noticed that the district here referred to, though now among the most hopelessly waste in France, was very productive even down to so late a period as the commencement of the French Revolution. Arthur Young, writing in 1789, says,—‘ About Barcelonette, and in the highest parts of the mountains, the hill-pastures feed a million of sheep, besides large herds of other cattle ;’ and he adds,—‘ With such a soil, and in such a climate, we are not to suppose a country barren because it is mountainous. The valleys I have visited are in general beautiful.’ He ascribes the same character to the provinces of Dauphiny, Provence, and Auvergne, and though he visited, with the eye of an attentive and practised observer, many of the scenes since blasted with the wild desolation described by Blanqui, the Durance and a part of the ‘course of the Loire are the only streams he mentions as inflicting serious injury by their floods. The ravages of the torrents had, indeed, as we have seen, commenced earlier in some other localities, but we are authorized to infer that they were, in Young’s time, too limited in range, and relatively too insignificant, to require notice in a general view of the provinces where they have now ruined so large a proportion of the soil.” After giving a picture of the devastations wrought by the Ardéche, which I shall afterwards have occasion to quote, he goes on to say,—“ As I have 1 136 LITERATURE ON TORRENTS. before remarked, I have taken my illustrations of the action of torrents and mountain streams principally from French authorities, bécause the’ facts recorded by them are chiefly of recent occurrence, and: as they have been collected with much care and described with great fulness of detail, the information furnished by them is not only more trustworthy, but both more complete and more accessible than that which can be gathered from-any other source. It is not to be supposed, however, that the countries adjacent to France have escaped the consequences of a like improvidence. The southern flanks of the Alps, and, in a less degree, the northern slope of these mountains and the whole chain of the Pyrenees, afford equally striking examples of the evils resulting from the wanton sacrifice of nature’s safeguards. But I can afford space for few details, and as an illustration of the extent of these evils in Italy, I shall barely observe that it was calcula- ted ten years ago that four-tenths of the area of the Ligurian provinces had been washed away or rendered incapable of cultivation in consequence of the felling of the woods. “ Highly coloured as these pictures seem, they are not exaggerated, although the hasty tourist through Southern France, Switzerland, the Tyrol, and Northern Italy, finding little in his high-road experiences to. justify them, might suppose them so. The lines of communication by locomotive-train and diligence lead generally over safer ground, and it is only when they ascend the Alpine passes und traverse the mountain chains, that scenes somewhat resembling those just described fall under the eye of the ordinary traveller. But the extension of the sphere of devastation, by the degradation of the mountains and the transportation of the débris, is producing analogous effects upon the lower ridges of the Alps and ‘the plains which skirt them ; and even now one needs but an hour’s departure from some great thoroughfares to reach sites where the genius of destruction revels as wildly as in some of the most frightful of the abysses which Blanqui has painted.” “ According to Arthur Young,” who travelled in France Italy, and Spain, in 1789, says Marsh, “on the lower Po, where the surface of the river at high water has been elevated considerably above the level of the adjacent fields by diking, the peasants in his time frequently endeavoured to secure their grounds against threatened devastation through the bursting of the dikes, by crossing the river when the danger became imminent and opening a cut in the opposite bank, thus saving their own property by flooding their neighbours’. He adds, that at high-water the navigation of the river was absolutely interdicted, except to mail and passenger boats, and that the guards fired upon all others ; the object of the prohibition being to prevent the peasants from resorting to this measure of self-defence.” Strefileur quotes from Duile the following observations : ‘The channel of the Tyrolese brooks is often raised much above the valleys through which they flow. The bed of the Fersina is elevated high above the city of Trent, which lies near it. The Villerbach flows at a much more elevated level than that of the market-place of Neumarkt and Vill, and threatens to overwhelm both of them with its waters. The Talfer at Botzen is at least eveh with the roofs of the adjacent town, if not above them. The tower- steeples of the villages of Schlanders, Kortsch, and Laas, are lower than the surface of the Gadribach. The Saldurbach, at Schluderns, menaces the far lower village with destruction, and the chief town, Schwaz, is in similar danger from the Lahnbach,” PART III. LEGISLATIVE AND EXECUTIVE MEASURES TAKEN BY THE GOVERNMENT OF FRANCE, IN CONNECTION WITH REBOISEMENT AND GAZONNEMENT, AS REMEDIAL APPLICATIONS AGAINST DESTRUCTIVE TORRENTS, Tue term reboisement is one of modern origin, because that to which it is applied is only of modern date, and I know not an English term of similar import. By a periphrasis the thing may be described, but the conventional term is more convenient than the constant use of a periphrasis would be, and more explicit than a literal rendering of the term would be, or any English synonym with which I am acquainted. The term is applicable, strictly speaking, to re-planting with trees a place or a district previously clothed or adorned with forests. It is held by some atudents of forest science that there is a tendency in many species and genera of arborescent vegetable productions to encroach upon and take possession of all unoccupied land, and in the struggle of life to dispossess other plants—if these have previously taken possession of the land,—and if these cannot submit to their domination. The names of places innumerable in various parts of Europe—Britain and the Continent alike—are terms applicable, strictly speaking, only to various forms of wooded land, and supply a presumptive proof that these were once forest homes. Marsh says,—‘‘ We may rank among historical evidences on this point, if not technically among historical records, old geographical names and terminations, etymologically indicating forest or grove, which are s0 common in many parts of the eastern continent now entirely stripped of woods—such as, in southern Europe, Breuil, Broglio, Brolio, Brolo ; in northern, Briihl, and the endings dean, den, don, han, holt, horst, hurst, lund, shaw, shot, skog, skov, wald, weald, wold, wood. “The island of Madiera, whose noble forests were devastated by fire not long after its colonization by European settlers, takes its name from the Portugese name for wood.” And history, properly so called, confirms the conclusion that the whole of Central Europe at least may be considered as having been one vast forest, such as now extends over the northern governments of Russia and the northern territorities of America. And there are numerous indications, ‘both historical and physical, that the whole of the High Alps had been at one time richly wooded. Hence originated the application of the term in question to the projected sylvicultural operations there, and its subse- quent application to all similar operations wheresoever prosecuted. The term gazonnement I have also retained, being unable to render it by any English synonym which would be equally explicit and equally comprehensive. The English term turf is generally, though not necessarily, associated exclusively with grass, or with turf which is largely composed of grass, Gazonnement is used in regard to a turf formed largely, and in many cages P 138 LEGISLATION ON TORRENTS, exclusively, of what may be designated herbs, in contradistinction to grasses ; and the term is more convenient and less pedantic than any I could devise. Though it is only of late that prominence has been given to reboisement and gazonnement in the legislation of France, the evil they are employed to arrest and remedy early commanded the attention of her legislators, Tn 1669 was issued an Ordinance by Colbert, regulating woods and waters in which déboisements, or the destruction of woods, is forbidden: to com- munities. There is evidence that a great part of the Alps had by that time been completely déboissée, or cleared of forests, This and similar déboisements the forest economists and students of forest science in France sought to remedy by an extensive system of sylvi- culture,—replanting trees where forests had been destroyed, and planting trees where never tree had grown before. An edict, issued by Humbert Dauphin in the 14th century, forbids clearings in the Briangonais, assigning, among other reasons for doing so, the resistance presented by the woods to avalanches and other evils. The archives of the Benedictine Monastery of Boscodon, preserved in the church Wotre-Dame-d’ Embrun, embody a record of a great many contentions, or legal proceedings, relative to forest depredations. It is the most common subject of these archives during a period extending over five centuries, and one which provoked numerous formal excommunications. From these archives it may be seen, by a host of facts, that the forests had then come to be a rare and precious thing—the result of long-continued fellings,—and in the fate of the monastery already referred to we see the consequence of these. Latterly, previous to the employment of reboisement and gazonnement as means of extinguishing torrents, dikes or embankments were what were chiefly employed as means of arresting the ravages and devastations of these. When a river-bank, throughout a considerable extent, was destroyed by a torrent, the proprietors affected thereby met and constituted a syndicate or council, An application was made to the prefect ; he appointed an engineer of roads and bridges to examine the locality, and if necessary to prepare a specification of the works required for the defence of the river. The work, when approved, was decreed. The engineer superintended the execution of it, and sanctioned delivery. The expense was then apportioned amongst those who were interested, conformably to a scheme prepared by the syndics. : The whole procedure is prescribed by a special decree, which subjects torrents to a defined régime, and places them under the immediate super- intendence of the Administration. The following is a translation of this decree :— “Decree of the 4th thermidor, an NTIT., relative to torrents of the department of the High Alps :— “Art. 1, In the communes of the High Alps, which are exposed to the eruptions and inundations of rivers and torrents, the mayors, after having submitted the matter for consideration to the municipal councils, shall make application in the usual form to the prefect of the department for authority to execute repairs, or other necessary works. In urgent cases they may summon the municipal councils for this purpose without a special permission, DECREE OF THERMIDOR, AN X11, 139 “Art. 2, The prefect shall appoint an ingénieur des ponts et chaussées to examine the spots exposed, to prepare a plan of the places, and to prepare specifications and estimates, which shall be communicated to the municipal councils ; and after they have made their remarks, the prefect shall give the authority if required. “ Art. 3. If the works to be executed affect only private parties, the prefect shall nominate a commission of five individuals from among the principal proprietors interested, who shall choose from amongst themselves a syndic, to deliberate on the utility or the inconveniences of the works demanded. “ Art. 4. The prefect shall then commission an engineer to prepare plans and estimates, which shall be communicated to the commission, as is ie scribed for the municipal councils in Art. 2. “ Art. 5, In cases where the works to be executed would effect many communes who would not act in concert, the demand of the municipal council making the application shall be communicated to the other municipal councils, and the prefect shall then proceed, with regard to all the councils, conformably to Art. 2. “ Art. 6. When the neglect—be it of one or more private parties, be it of one or more communes—to make dikes, curages—2.e., clearing away of stones and deposits in the channel, or artificial structures, along a torrent or an unnavigable river, shall expose the territory abutting upon it in a way ‘prejudicial to the public weal, the prefect, on complaints which may have been made to him, shall order a report of an ingénieur des ponts et chaussées ; this report shall be communicated to the parties interested, with injunctions to give their answers in writing within eight days, and the council of the prefecture shall decide on the disputes which may result. “ Art. 7. If a dike interest a commune in general, and some private parties oppose the construction of it, the municipal council shall be consulted, and the opposition shall be submitted to the council of the prefecture. “‘ Art. 8. In all the cases specified, when the time allowed shall have expired, if all the parties interested shall have given their consent, or if there be no protests, the adjudication of the works, according as they have been determined and resolved upon, shall be made in the usual forms before such functionary as the prefect shall appoint in the presence of the parties - interested, or those there duly summoned by posted bills and the usual ordinary publication of such announcements. “Art. 9. The amount thus adjudicated shall be apportioned according to the extent of interest attaching to their property, according to a scheme of division which the prefect shall make legally obligatory, accord to the law of the 14th floréal, an XI.; and the council of the prefecture shall decide protests relative to this partition of the expense. “ Art, 10. The adjudicators shall be paid the expense of their adjudication, in virtue of an order delivered by the prefect, on certification of the works ~ having been taken over and delivered by the engineer charged with the management of the works. The parties liable shall be forced to pay in the form prescribed by the law of the 14th floréal, an XT. “Art. 11. No proprietor can be taxed for contributions to such works in the course of any one year, beyond a fourth part of his net revenue, after deduction of every other tax.” Of this decree Surell says, that it did great service to the department of 140 LEGISLATION ON TORRENTS. the High Alps, because it subjected to a fixed rule all the works which otherwise would have been executed as chance might determine, perhaps with mutual detriment and damage to one and another of the works executed. ‘And he adds, that, if it has not yielded all the fruit which might have been expected, it may be well to take into account the hostile spirit which generally animates the proprietors of the opposite banks of a river, and which, unhappily, often prevents their union and co-operation in the construction of such an embankment as would be the only means of rendering the defence perfectly harmless and productive of the greatest amount of benefit possible. | Valuable information in regard to the subject of this decree may be found _in Notice des principales lois décrets ordonnances, cc., relatif aux riviéres, ‘torrents, &c., par Morisot, Chef de bureau & la prefecture des Basses-Alpes, 1821. There exists also in the papers preserved in the prefecture of the High Alps an excellent raglement, which developes fully the decree of the 4h thermidor, which was drawn out in 1802 by M. Gauthier, councillor of the prefecture. ’ By an Act of 16th September 1806, obtained on demand of M. Ladoucette, who had been prefect of the High Alps, this decree was extended to the Drome and the Lower Alps. . In a law bearing the date of 16th September 1807, there were embodied several enactments somewhat at variance, if not directly opposed, to the requirements of that decree. And the question was subsequently raised, whether this law were not virtually an abrogation or rescinding of the decree. To those who are desirous only of learning what may be learned relative to practical measures, sanctioned and tested, and approved or abandoned by the Government in dealing with this matter, this question is of importance mainly as indicative of the importance attached to the subject by the Legislature and Administration of the country. The importance of this legislation, under this view of the case, arises from the probability which there is that it will be long before the more efficient remedies ‘proposed by Favre, Dugied, and Surell, will be extensively adopted in newly- peopled territories, and from the probability that meanwhile the adoption -of the less efficient measures which occupy only a secondary position in the comprehensive projects submitted by them may be advocated as temporary, if not as final, measures to be adopted; and it may be advantageous to know what has been done in similar circumstances by others, and with what results. According to Art. 33 of the law of 16th September 1807, it is enacted,— “When it is proposec to construct sea-dikes against rivers, streams, and torrents—navigable and not navigable alike—the necessity for this being done shall be determined by the Government, and the expense borne by the property thus protected in the ratio of the interest in the work, excepting in cases in which the Government shall deem this of public utility, and rant all necessary assistance from the public treasury. . . . “ Art, 34, The forms of procedure hereby established, and the interven- tion of a Commission, shall be applicable to the carrying out of the preceding Article.” . . . It is in these forms of procedure alone that there is aught opposed to the decree previously enacted. By this law there were established two com- missions, the Syndicate, and another designated a Special Commission. By the decree there was established only the Syndicate, and the powers of this LAW OF 16TH SEPTEMBER 1807. 141 were not exactly equivalent to that of the two commissions now established. The law of 1807 gives to the Special Commission not only the right to pre- pare or to verify and sanction a roll of the valuation of lands interested in the works, but also the power of regulatiug ex-propriations, or transfers to the government, of lands requiring to be used in the execution of the enter- prise, where this cannot otherwise be effected. In regard to the inquest de commodo et incommodo, or the necessity of- the measure and the disadvantages which the execution of it might entail on any whose interests might thereby suffer,—it had been the custom that every proposal should be lodged in the Mayor’s Office, with summons to all concerned to put themselves in communication with that office. Objections were recorded, discussed by the Syndical Commission, addressed to the prefect, and then submitted to the Council of the Prefecture. By the law of 1807 it was enacted that objections and protests should be sent by the prefect before the Special Commission, which should decide finally on these. The construction of a dike, according to the decree, required no other sanction than that of the prefect, who considered the projects of the engineers, decided whether the construction should or should not be carried out, and gave a final decision on all disputed points. The formalities prescribed by the law of 1807 are more complicated, and require the intervention of the superior administration. In regard to the course usually followed in preparing the roll of contri- butions towards meeting the expense of constructing such a dike, required of the several parties interesed, M. Surell supplies the following information : “The work is begun by arranging all the properties interested in a certain number of classes, determined by the greater or lesser probability of their suffering from inundation. There are thus classified together all properties which have nearly the same chance of being invaded by the torrent; and to each class is given a number, designed to be representative of this probability alone : one class, considered twice as liable to invasion as another, is marked by a number double that of the latter This done, the area of each property is multiplied by the number assigned to the class to which it belongs, as indicative of the chance to which it is exposed. And the total expense is assigned proportionally to the product.” Thus is the roll of liabilities prepared; but it is pointed out by Surell that it is neither the most exact, nor the most equitable plan which might be adopted. There may be two properties equally liable, and of equal extent, of very different pecuniary value. The soil of the one may be better than that of the other; it may have been more improved, it may be of easier access, or it may have upon it dwelling-houses or mansions, and other ameni- ties, which would enhance its price if it were sold. Should this be destroyed, the proprietor would suffer a proportionally greater loss; having thus a greater interest in the maintenance of the dike, he ought to be required to pay a greater contribution towards the execution of the work ; and it follows, that the rule commonly adopted by the syndic, according to which both pay alike, is neither rational nor equitable. The payment ought to be calculated in the same way as the law of probabilities is applied at the gaming-table. And for this purpose there should be determined—(1) The probability of inundation in regard to each property ; and (2) The value of each property menaced. And the product of these, multiplied the one by the other, will give the proper proportion of the expense to be borne by each property. The determination of the first of these factors is somewhat difficult, but 142 LEGISLATION ON TORRENTS. it is not impracticable. In normal cases of inundations, of a temporary character—the waters returning again to their usual bed—there may be ascertained what marks exist of inundations which have occurred within the most protracted period during which they can be enumerated—say 80 years. These indications supply a point of departure, in determining with exactitude levels following the inclination of the river bed, so arranged as to include in one line all the corresponding marks of one flood. The whole ground, from the river to the most distant part reached by an inundation, would thus be divided into a certain number of zones, subject each to a different chance of inundation. All the lands included in one zone would constitute a class subject to the same chance. What this is has next to be determined ; and that may be done thus :—If the portions included in the zone nearest to the river have been flooded upon an average three times every year, the chance of inundation may be represented by the fraction a While the zone most remote, if flooded only once in the 1 course of the fifty years, would be represented by the fraction igo 2 The value of the property in each zone being then determined, representing the value by v v' v”, and the chances by p p’ p”, the-equivalent of the extent to which the different classes were interested would be expressed by the products p », p' v’, p” v”, &c.; and to determine the quota of each party interestec, it is only necessary to multiply the value of the property by the chance of the class to which it belongs, and the product by a constant co-efficient, determined in such a way that the sum of the shares of all interested will equal the whole expense. This co-efficient may be deter- mined by the following equation, in which the total expenses, represented by S, co-efficient = &e. vx pul x piv" It is an intricate question, and leaves much to be determined by the syndic ; but the classes once formed, what follows is rigorously just. It has been stated, that it has been questioned whether the law of 1807, in superseding, abrogated the decree of 4th Thermidor, an VIII. The question was raised in the Chamber of Deputies, on the 12th April 1837, by M. Jaubert, acting in the name of a commission appointed to examine a proposed law relative to the joint action of proprietors in works undertaken on rivers of greater and lesser size. This they considered it did, but others thought differently. That question has not now the interest it then excited. In the one may be seen a development of the other. Both related exclusively to the construction of dikes as means of protecting the land against the devastations of rivers and torrents. In 1797 appeared the work by Favre, advocating the creation of planta- tions as a means of more efficiently securing the object desired. The date of M. Dugied’s work, advocating the same measure, I have not ascertained, In 1841 was published, printed by order of the Minister of Public Works the work by Surell, shewing the primary and almost absolute importance of plantation, while the topical application of dikes may be necessary as a secondary and subsidiary means of preventing devastations. And the legislation of the present is of national application ; these laws were of more limited local application. In entering upon the consideration of this later legislation, it may be mentioned that from the first it was maintained by Surell that as things RIGHTS OF PROPRIETORS, 143 then were in France nothing satisfactory could be done without Govern- ment interference ; that the problem to be solved was the prevention of the formation of new torrents, and the arrest of the ravages which were being made by torrents already formed ; that the battle-field must be in the basin drained by the torrent, and that a system of extinction must be followed ; ~ that in view of the public interest it was vain to trust to the prudence of communes, to the publication of information and warnings, or to moral suasion in any form ; that both the number of cattle depastured and the extent of the pastures must be restricted, and the introduction of cattle and sheep, other than those of the commune, prohibited ; that agricultural operations which do not promote the carrying away of the soil should be allowed without restriction, but that such as have that effect should only be tolerated on slopes not exceeding a prescribed inclination—compensation being given, if necessary, for loss which might be sustained in consequence of this restriction, but enforcing it with rigour: the circumstances of the locality being exceptional, exceptional legislation might be requisite. Further, the forests having an exceptional importance—being required not only to meet daily recurring wants of the population, but to preserve the very soil—it was necessary that their conservation should be secured, and measures taken to effect their extension. And to these preliminary measures had to be added the more direct measures detailed or suggested in his treatise, of which a réswmé has been given. There might be private rights in the way of the execution of these works, and the conflicting claims of the public interest and of private property must be reconciled. This might be done, according to circumstances, by the Government taking possession, with compensation to the proprietor, as is done in carrying out other works carried out for the public good, or by requiring of the proprietors that they themselves should.plant the ground with woods, and giving to them every just and reasonable assistance in the execution of the work, The poverty of many of the proprietors might make it impossible for them to meet the expense; and the restrictions imposed upon them by some of the preliminary measures required would entail upon them a considerable sacrifice. The measure, moreover, was one affecting the public interest as really as do many of the public works—such as embankments, roads, bridges, and the improvement of mountain passes,—while the outlay , by the State might be counterbalanced in a great measure by a diminution of outlay on these, through the prevention of injuries now done to these by torrents ; and, as shown by M. Dugied, the forests would in course of time become a source of revenue, and, according to others, they would tend to improve the climate. Such are some of the considerations adduced by M. Surell as reasons for the Government taking up the work. Having done this, he gave details of what. measures he considered would be requisite in carrying out the work: the initiative to be taken by the Government ; the objections to be anticipated, and the means of meeting these, whether they might take the form of an allegation that it was impossible to plant the mountains with woods, or of an allegation that if this were done it would not suffice to cause the. torrents to disappear, or of objections to different regulations which it would be necessary to ca: out in connection with the execution of the work, some relating to rights of property, some to rights of pasturage, some to one thing, some to another, 144 LEGISLATION ON TORRENTS. And, having done this, he proceeded to draw a fascinating picture of the wide-spread felicity which was to follow the execution of the project. He had previously given the saddening picture of Dévoluy, which I have cited in the Introduction. And he proceeds to show what had been done in France when it was perceived that the fruits of the country were being destroyed ; he details the evils which followed in the train of that destruction, the alleviations of these secured by the inhabitants of the plains, but which were unattainable by the inhabitants of the mountains, and the privations to which they had been in consequence reduced. “There may be seen,” says he, “here in one small valley (that of Lagrave) the inhabitants reduced to the necessity, in order to heat their houses and cook their provisions, to burn cow-dung formed into bricks and hardened in the sunshine. This disreputable fuel saturates with its smoke their huts, their clothes, the air which they breathe, and even the food which they eat—the whole atmosphere of the country is filled with it. Now if they have recourse to such a fuel, it is not that the country is absolutely devoid of fuel; it is, on the contrary, very richly supplied, as there are many beds of anthracite under active exploitation. But one may easily imagine that this mineral, being very heavy, if it be necessary to transport it on the backs of mules or of men to great elevations, across rocks and perilous slopes, the fatigue and consequent price of transport will raise the cost of it to such a point that the great bulk of the poor people must renounce the use of it. And the consequence is, these mines, which would be so valuable in a plain, here benefit only such of the inhabitants as live in the immediate vicinity of them, and they remain almost unused by all living beyond a radius of some leagues from the spot.” He contends that, in order that the mountains may be habitable, they must be wooded ; and that the total annihilation of forests will necessitate the emigration of the population. But the difference between the destruc- tion of forests on the mountains and on the plains, says he, stops not here, “Tf a forest disappear.on the plain it is to give place to agriculture, it is the substitution of one product of the soil for another, and the substitution often leaves nothing to be regretted. But if, on the other hand, you fell an old forest which covers the flanks of a mountain, immediately everything is upset and overturned, The storms and the ravines cut up the slopes, the vegetable soil is soon washed away, and with it all fertility and verdure, No more fields! No more cultivation! Delivered defenceless to the attacks of the waters, eaten down to its very entrails by the torrents, and sinking at last under its own weight, the mountain, as if crushed and spread out, is seen rolling its material into the plain, and this it buries under its debris and involves in its own ruin. It is true, it happens here as in the plains, that wood is every day felled to free soil for the plough, and those who root out the trees only do so for the profit which follows. But we must not confound the ephemeral and illusory profits which are obtained by them with the lasting advantage and real benefit which follow such operations in the plains. “ The first years following immediately the rooting up of trees on a moun- tain produce excellent crops, because of the quantity of humus left behind them in the soil by the trees. But this valuable earth, the less stable in propor- tion as it is productive, does not remain long on the slopes ; at the end ofa short time it is dispersed, the sterile subsoil makes its appearance, and the unreasonable proprietor loses his property from having wished to constrain i REVOLUTION OF 1848. 145 it to produce more than its nature would permit. We see too often the old story of the goose which laid golden eggs practically exhibited in the mountains, notwithstanding the instructions a thousand times repeated by experience. A recent case in point, says he, is supplied by the rooting out of woods on the mountains of Champsaur. This rooting out of woods on declivities is always followed with disastrous consequences ; and the destruction of forests, practised almost always without inconvenience on the plains, becomes, on the contrary, in the mountains the most disastrous of disturbing operations. It breaks up the equilibrium of the land, and brings back the disorder of ancient chaos. After having wrenched from the inhabitants the usufruct of the forests, it carries off the soil which nourished them, thus pursuing man with hunger, if he submit unresistingly to the privation of wood. And in eloquent and stirring appeal, called forth by what he foresaw, he urged the reboisement of the mountains, whatever the expense might be. The appeal appeared to have been made in vain—if in this world, in which no atom of matter appears to be destroyed, and no form of physical force to be lost, any counsel, good and true, can be given in vain. Years, at least, passed away—as nearly fifty years had passed away after Fabre had spoken something similar—and nothing was done. But at length, in process of time, there was a resurrection of the two witnesses, their testimony was again called for ; and the fulness of time being come, their testimony was listened to, and their counsels were adopted. In November 1840, the year before the publication of M. Surell’s work, there occurred a destructive inundation of the basin of the Rhone. Occur- ring at that late season of the year, all the crops had been gathered in, but the damage, notwithstanding this, was estimated at 72,000,000 of francs, or well-nigh £3,000,000 sterling. Several smaller floods of the Rhone subsequently occcurred in 1846, at a somewhat earlier period of the year, and occasioned a loss of 45,000,000 of francs, or £1,800,000. “Tf these floods,” writes Dumond, “instead of happening in October, between harvest and seed-time, had occurred before the crops were secured, the damage would have been reckoned by hundreds of millions.” These inundations in 1840 and 1846 made the question of forests an order of the day; remedial measures, which were demanded and were opposed on all hands, became the subject of careful consideration and study; and the Government was about to promote a general law for the regulation of all rooting out of woods, and to reform the forest code, when the revolu- tion of 1848 broke out. The effect of this upon the forests was soon felt, but in another way. Within thirteen days after installation the Provisional Government authorised, by decree of 9th March, the sale of a considerable portion of the crown forests, and all the forests of the civil list. On 30th June 1848, the State ceded to the Bank of France 75,000 hectares of forest, as security for a loan of 150,000,000 of francs, On 4th December 1848 the National Assembly discussed the forest budget ; in vain did the Minister and the Director-General defend their Administration ; in vain did the tribune re-echo the famous words of Colbert —La France périra faute de bois; retrenchment and economy were the order of the day, and the different forest services saw themselves threat- Q 146 LEGISLATION ON TORRENTS, ened with dissolution. Particulars are given in the Annales forestiers, of December 1848 and January 1849. This, however, proved but a passing storm. On the establishment of the empire the Forest Administration, promptly re-constituted, shared after 1852 the great impulse which was given to public works. There are decrees dated 17th and 27th March, and laws of the 12th April 1853, of 5th May 1855, of 28th July 1860, and of 8th June 1864, which have authorised alienations or extensive fellings of the State forests. These may be considered comparatively unimportant operations, and the roceeds of them were to be employed in works of reproduction. But when, in 1865, the Government proposed the alienation of forest domains to the extent of 100,000,000 of francs, to be applied to the commencement and prosecution of public works, public opinion was roused, and, alarmed by the proposal, publicists of every shade, politicians, savants, littera- teurs, &c., combined their efforts and raised a crusade against the projet de loi, which made it necessary to withdraw it. Meanwhile another inundation, or the cotemporaneous occurrence of a num- ber of inundations, had given a new direction to men’s thoughts on the subject. In the month of May 1856 violent and almost uninterrupted rains fell throughout France, and most of the river-basins of the country were inundated to an extraordinary extent. In the valleys of the Loire and its affluents about a million of acres, including many towns and villages, were laid under water, and the amount of the pecuniary damage was almost incalculable. The flood was not less destructive in the valley of the Rhone, and an invasion by a hostile army, it was said, could hardly have been more disastrous to the inhabitants of the plains than was this terrible deluge. “Tn the fifteen years between these two great floods,” says Marsh, “ the population and the rural improvements of the river valleys had much increased. Common roads, bridges, and railways had been multiplied and extended ; telegraph lines had been constructed,—all of which shared in the general ruin, and hence greater and more diversified interests were affected by the catastrophe of 1856 than by any former like calamity. The great flood of 1840 had excited the attention and roused the sympathies of the French people, and the subject was invested with new interest by the still more formidable character of the inundations of 1856. It was felt that these scourges had ceased to be a matter of merely local concern, for, although they bore most heavily on those whose homes and fields were situated within the immediate reach of the swelling waters, yet they frequently destroyed harvests valuable enough to be a matter of national interest, endangered the personal security of the population of important political centres, interrupted communication for days and even weeks together on great lines of traffic and travel, thus severing, as it were, all South-Western France from the rest of the empire, and finally threatening to produce great and permanent geographical changes. The well-being of the whole commonwealth was seen to be involved in preventing the recurrence and in limiting the range of such devastations.” “The inundations of 1846, and more especially those of 1856,” wrote Cézanne, “ compelled attention to be given to the conservation of the forests. In proportion to the greatness of the prosperity which prevailed, and the profound feeling of security which had Julled so many to sleep, the more severe and the more unexpected seemed the disasters thus occasioned,” REPORT BY MINISTER OF FINANCE, 1860. 147 A great complaint arose ; this was followed by a keen controversy ; the Head of the Government took part in this; a letter from him to the Minister of Public Works, under date 19th July 1856, published over the whole of France, gave a résumé of the popular movement ; and, founded on information elicited, there was issued in his name, under date of 5th January 1860, a programme of procedure, which was followed by a projet de lor, which was submitted to the Emperor with the following report by M. Magne, Minister of Finance :— “Paris, 2nd Feb. 1860. Srre,—‘“ The attention of your Majesty has been given at different times to the dangers which result from the deforesting of the mountains. At the time of the inundations of 1859, you were led to point out that deforesting was one of the causes of the evils which had then afflicted the country ; in the programme traced in the letter of your Majesty is included, in the innumeration of the great administrative measures destined to develope the public prosperity, the clearance of forests on plains, and the reforesting of the mountains. “A law passed in the last Legislative Session has given new facilities for the clearance of forests situated on the plain. This law, long waited for, is one of the recent benefits conferred by the Imperial Government; it realizes its liberal views in what. relates to woods belonging to private proprietors. There remains to be proposed, as a necessary complement to this, a law for the reforesting of the mountains. “No legislative measure of any importance on this subject has been adopted by the Governments which have preceded that of your Majesty. The old edicts, and the ordinances anterior to 1789, contain only exceptional measures to arrest the progress of deforesting. The code forestier was con- ceived in the same spirit ; there is found there a series of arrangements designed to restrain the abuse of depasturing, but only one arrangement was introduced to promote reforesting ; it is Art. 225, which exempts from tax- ation, for a period of twenty years, woods sown and planted on the summit and on the declivity of the mountains. The law adopted last year, in regard to the clearance of woods belonging to private parties, prolonged this exemption of taxation to 30 years. “But, notwithstanding the new extension given by the Government of your Majesty to this favourable arrangement, one knows not how we can await the very important results which must follow. The sowing of trees and plantations, especially those on the mountains, profit the future more than the present, and general interests more than the interests of individuals: hence the necessity for efficacious measures, and for the direct intervention of the State. This intervention has for a long time been urgently called for. Since 1843, sixty-three general councils have urged the necessity of measures being taken for the reforesting of the mountains. A report and a projet de loi were prepared by the director-general of forests in 1845. This projet de loi, remitted for examination to a commission composed of forest administrators and distinguished savants, was amended in many parts, and submitted to the Chamber of Deputies in the session 1847. The report which was presented by the commission admitted the importance which attached to the question, but also the uncertainty which prevailed in opinions relative to the measures which should be adopted ; and nothing came of this projet de lor. 148 LEGISLATION ON TORRENTS. “But the greater part of the general councils have not ceased to call, year by year, for legislative measures, designed to favour the reforesting of the mountains. Many have even voted subventions with this view. There may be cited, more especially, the general councils of the Puy-de-dome, of the Lozére, of the Bouches-du-rhéne, of l Ariége, and of l’Ain; and lastly, a certain number of communes have imposed on themselves sacrifices, and have taken the initiative in works of reforesting ; but these efforts, which attest the urgency of the need, are not in keeping with the magnitude of the evil, and they must remain, moreovef, inoperative in securing the co-operation of the State. It is this co-operation which your Majesty has sought to secure to the population of the mountains. “The region in which reforesting is becoming most urgently necessary comprises a certain number of departments, furrowed by many chains of mountains, of which the principal, and the most deforested, are the Alps, the Pyrenees, the Cevennes, and the mountains of Auvergne. It isin these chains of mountains which the principal affluents of our rivers, and the rivers themselves, of which the basins are most exposed to inundations—the Rhone, the Isére, the Loire, the Durance, the Garonne, &c.—take their rise. “Statistics have been prepared at different times to determine the extent of lands susceptible of reforesting in the mountain regions of France. These, carried out more fully and completed of late years by the forest administrators, have been verified by special reports which had been required of conservators in 1859. The results have been tabulated, and show that lands susceptible of reforesting, in the departments the most threatened by the denudation of their declivities, may be estimated proximately to be in extent 1,133,000 hectares. These lands belong to the State, to communes, and to private proprietors. “No legislative arrangement appears to be necessary in regard to lands belonging to the State ; it suffices to secure the reforesting of these that special credits be introduced into the budget of the administration of the forests. Your Majesty’s Government has already taken the initiative in this matter, and since 1855 a sum of 500,000 francs has been appropriated annually to works of replenishing in the State forests. This appropriation has allowed of a great reduction of the void spaces existing in the forests, and of works being executed during the last five years on lands situated on the mountains or on the declivities, and thus has led to the reforesting of fourteen thousand hectares. By continuing this appropriation of 500,000 francs for a certain number of years, it is belisved that the forty thousand hectares of lands belonging to the State in these departments of the moun- tains may be completely replanted with woods. “But it is not the same with lands belonging to communes, to public bodies, and to private proprietors ; the replantings executed by them on these lands are the result of a few isolated efforts—trials left to themselves, without direction and without encouragement. The State ought to inter- fere, to give to these works the impulse demanded by the general interest ; and a law is required to point out the importance of this joint action, and to determine the conditions of it. “For the greater part of the lands situated on mountains, the inter- vention of the State can only consist in subventions granted to private proprietors, to communes, and to public bodies. These subventions might consist, in those which relate to private proprietors, in supplying to them plants and seeds before the execution of the works, and in the subsequent REPORT BY MINISTER OF FINANCE, 1860. 149 distribution of premiums; in those which relate to communes and to public bodies, in subventions in money which might be granted before the execu- tion of the works, but the grants should be proportionate to the wants, to the resources, and to the sacrifices made by the several departments and by the several communes. “ The projets de lot, which have been proposed for the replanting of the mountains with woods, in 1845 and 1847, have recognized the necessity of authorising, in a public interest so very great, the distribution of subven- tions and of premiums, as well as the supply of plants and of seeds. This first part of the projet de loi need not then raise the question of principle. The Administration will only require to take the necessary measures to see that the subventions be distributed with discernment. In point of fact, it is not necessary that the whole of the lands susceptible of replanting should be covered with woods; in many places a covering of the land with turf may suffice to ensure the maintenance of the land on the mountain, and, where the planting with wood is a recognized advantage, the subventions ought not to have as their result to substitute the action of the State for the initiation of the work by the individual. “ Communes which may be disposed to demand too high subventions, regard being had to the sacrifices which they impose upon themselves, should only receive from the State co-operation subject to certain conditions, which may perhaps appear somewhat severe, such as a proportional participation in the forests created on the communal lands. ‘ It would not be just, indeed, that certain privileged communes should be able to draw to themselves all the benefit of the subvention. The benefit, in order to its being shared by a great many, should not be applied to each otherwise than in a certain proportion. If this proportion be exceeded, the pecuniary co-operation of the State should assume another character, and the subvention become an advance to be paid back, at least in part, to the public treasury, through a cession of a portion of the lands, the principal value of which will have arisen from the replanting of them with woods. “ At the same time, it is impossible not to foresee that, notwithstanding the subventions offered, and notwithstanding the advances which the State may be willing to make, there may be communes, or private proprietors, utterly unable to execute the replanting, and yet on certain determinate places, replanting may be demanded, not only by manifest public interest, but, so to speak, by an imperious necessity. “ There are, on the mountains, places which are more especially threatened by the violence of rivers, by the impetuosity of torrents, and by the fall of avalanches or of rocks. Such, for example, are certain lands on steep declivities, situated on the sides, or at the debouche of torrents; such are villages exposed without shelter to catastrophes which are in some measure periodical. The reformation of wooded masses, designed to arrest the ravages cf waters, and to divert from the places imperilled disastrous effects of great natural disturbances, is in the highest degree a work of public interest. In such masses of woods as are desired every thing combines to offer resistance to the scourges which desolate the mountains : the roots of trees keep the ground in its place and consolidate the soil, the branches form a shelter against the storm and wind, the leaves fertilize the light bed of vegetable earth covering the rock. “The reboisement presents, then, in these exceptional cases, and at certain determinate places, a character of public utility such that the necessary 150 LEGISLATION ON TORRENTS. works to reconstitute masses of woods should be rendered obligatory, and, if need be, be executed at the expense of the State. “Imperial decrees, issued after the observance of forms of procedure which shall give satisfactory guarantees to all interests, should specify the boundaries of these lands. The Council of State would then have to ascertain whether within these exceptional boundaries ex-propriation for the sake of public, utility could not be applied to lands belonging to private proprietors, and whether the temporary occupation of lands belonging to communes ought not to take place conformably to the principles laid down by the law of 1857, relative to the plantation of the communes of the Gironde and of the Landes. “ But the provisions of this part of the projet de lot should be applied with such reserve as not to lead to hasty changes in the general habits of the population of the mountains. It should be applied, in the first instance, to places in regard to which it is already seen and acknowledged that the replanting of them with trees would be a benefit. If in certain communes it be the case that the population are without cause disturbed by every attempt at replanting, considering this as a hindrance to the enjoyment of the right of pasturage, there are, on the other hand, others struck by the imminence of the dangers by which they are threatened, or pressed by the scarcity of wood in regions in which the snow lies on the ground eight or ten months of the year; and, considering the replanting of woods as a measure of protection and safety, they urgently solicit it, as is notably the case in the departments of the Haute-Loire and of Puy-de-Dome. In certain mountain countries, then, the co-operation of the population is now certain to be given to works of replanting. This co-operation guarantees success in it, and the importance of the results to be obtained will little by little enlighten the communes which are less favourably disposed towards the advantages of the measures prescribed by the Government. “The Administration, however, should not forget that pasturage is one of the necessary conditions of life to the dwellers on the mountains. The interest of the shepherd population ought then to be treated with the greatest care. But this same interest is closely allied to that of the opera- tions of replanting, for the abuse of depasturing is not less hurtful to the conservation of the pasturages than it is to the conservation of the forests. In the day when the forests shall disappear from the mountains it may be ' predicted with some measure of certainty that the day is not distant when the pasturages shall disappear in the train of the forests. “Tn the department of the Basses-Alpes, for instance, where the abuse of the pasturage, and the incursion of stranger flocks, known by the name of transhwmant flocks, have |occasioned disastrous consequences, the pasturage resources have rapidly diminished with the destruction of woods on the declivities, and the latest statistics have attested the impoverishment of the land and the emigration of the population. All the prefects of this depart- ment for forty years past have reported the progressively increasing serious- ness of the state of things there. Besides, do not the forests themselves supply in the mountains what is required in pasturage? If, during a period of some years, the shepherd would respect the forest sowings, the planta- tions, and the young fellings, till the wood has become capable of self-defence, the animals might then enter it, and there find abundant nourishment. And does not the pasturage present more valuable resources in the forests of the mountain than it does on the denuded slopes, where vegetation tends to disappear and to give placc to a sterile soil? REPORT BY MINISTER OF FINANCE, 1860. 151 “The replanting there is not less necessary in the interest of the shepherd of the mountain, than in the interest of the agriculturists of the valley, who are threatened by inundations ; and the legitimacy of the exceptional measures in certain determinate cases is justified by public interests of the very highest order. It would be possible, movever, to moderate the dreaded effect of these measures : there might be granted, for instanee, to private proprietors, after the reboisement of their lands, the power of re-entering on the proprietor- ship of these lands on repayment to the State of the indemnity of expropri- ation, and the expense of the works. The replanting with woods being effected, the public interest is secured, and the proprietor might be permit- ted to exercise a kind of action .of recovery within a determinate period. On the other hand, the State would thus recover a portion of the advances made, and might apply the amounts received to new works of reboisement. “So, also, might communes be permitted to recover possession of their wooded lands, on reimbursement to the State of the advances made; but more than this, they might be allowed, without making any reimbursement, to resume possession of one half of these lands, on ceding the other half of them absolutely to the State. “ These varied combinations will be appreciated at their true value by the Council of State, which will know how to reconcile the requirements of the public interest with the guarantees and arrangements due to private pro- prietors, and to communes. “It only remains to intimate to your Majesty the financial measures which it appears ought to be adopted, in order to the carrying out of the projet de lot. “ A sum of ten millions should be appropriated to subventions, and to works of replanting with woods on the mountains. The necessary resources for meeting this expense should be obtained through the sale of woods belonging to the State to a corresponding amount of ten millions, “ The alienation of these woods should take place successively, throughout a period of ten years, in such a way as to proportionate each year the resources obtained by the sale of woods on the plain to the allocations granted to the budget for replanting the mountains with woods. The Forest Administration should be charged with the double operation, and the Minister of Finance should be charged to see that the advances made from the treasury be covered by the payments received in the year. “For the success of the operation of replanting, as well as for the successful operation of the alienation of woods, it is not needful to urge on precipitately either the works to be executed, on the one hand, or, on the other hand, the sales to be effected. An allocation of a million per annum, devoted to replanting, is sufficient for the distribution of subventions and important premiums, and for the undertaking of somewhat considerable sowings and plantations within the exceptional boundaries specified by the Imperial Decrees. The corresponding annual alienations of woods to the value of a million can occasion no perturbations in the sales of landed pro- perty, or of fellings of timber. Hitherto, the success of alienations of woods has always been neutralised by the mass of operations going on at the time to meet the urgent requirements of a period of crisis. The alienation which will take place in carrying into execution the present law will be made in circumstances much more favourable, and there may be anticipated good results. “The woods of which the projected law proposes the alienation are those 152 LEGISLATION ON TORRENTS. comprised in Table I. of the law of the 5th March 1855; so the alienation of them has already been authorised by the Corps Législatif, as the sales authorised towards the raising of fifteen millions did not amount to more than about a sum of six millions. The woods designated in that table are, moreover, in the conditions determined by the programme of your Majesty. They are, in general, in lots of moderate contents situated in fertile plains, or woods, the clearing away of which has been already authorised. From the point of view of forest. economy, alienations limited to woods so circumstanced presents no inconvenience, while the reconstruction of extensive masses of woods on the mountains is seen to be of the first importance. “Such, Sire, is the general purport of the projet de loi, which I propose to your Majesty to submit to the consideration and examination of the Council of State. The eminent men who compose that Council will know how to improve the arrangements of that law. I have endeavoured, in the preparation of it, to enter into the spirit of the great foresight which deter- mined your Majesty to grant the concurrence of the State to the important work of the reboisement of the mountains.—I am, with the most profound respect, Sire, your Majesty’s most humble, most obedient servant and faith- ful subject, P. MAGNE.” In accordance with usage, the projet de loi, or draft of the Jaw proposed, was submitted to a Committee, along with an Exposé des motifs, or state- ment of reasons for its enactment, to which they were required to give consideration. And, in accordance with a report made by them, the law was enacted in the following terms :— “Law, of the 28th July 1860, on the Reboisement of the Mountains. “ Art. 1, Subventions may be granted to communes, to public bodies, and to private individuals, for the replanting with woods of lands situated on the summits or on the declivities of mountains, “Art, 2. These subventions may be made in grants of seeds, or of seedlings, or in premiums of money. “ These to be granted on account of the utility of the works, in view of the general interest ; and in the case of communes and public bodies, regard is to be had to their resources, to the sacrifices they have made, and to their need, and also to the sums granted by general councils for reforesting. “ Art. 3. Premiums in money, awarded to private individuals, cannot be delivered until after the execution of the works. “ Art. 4, In any case in which the public interest requires that the work of reforesting be made obligatory, in consequenee of the state of the ground, and the dangers resulting from this to lower-lying lands, this is done thus : “ Art. 5. An Imperial’ decree, issued through the Council of State, declares the public utility of the works, determines the boundary of the lands in which it is deemed necessary to carry out the work of reforesting, and limits the time within which the work must be done. ‘This decree is preceded by (1) an open inquest or inquiry in each of the communes interested in the works; (2) a deliberative discussion of the subject by the municipal councils of these communes, together with those of the more important of those which are circumjacent ; (3) the opinion of a special commission, composed of the prefect of the department, or his delegate, a member of the general council, a member of the council of the arrondisement or district, and two of the landed proprietors of the Law oF 28TH JULY 1860, 153. communes concerned ; (4) the opinionof tue council of the Arrondissement, and that of the General Council. “The procés-verbal, or attested minute specifying the lands, the diagram, or chart of the lands, and the specification of the works proposed, prepared by the Forest Administration with the co-operation and approval of an engineer of roads and bridges or mines, are to remain deposited in the office of the mayor during the inquest or inquiry, the duration of which is limited to a month, dating from the time of the prefectoral resolution, which prescribes the opening of the inquest and the convocation of the municipal council. “ Art. 6. The Imperial decree is to be published and posted up in the communes concerned. “The prefect, moreover, is to serve on the communes, on the public establishments, and on the private individuals concerned, extracts of the Imperial decree, containing severally what therein relates to the lands belonging to them. “The notification made to them is to state the limit of time within which the works of redoisement should be completed, and, if there be occasion for it, the subvention granted by the Administration, or the advances which they are prepared to make. “ Art. 7. If the lands comprised within the boundary determined by the Imperial decree belong to private individuals, these are required to declare if they intend themselves to effect the reborsement, and in that case they are held bound to execute the works within the period fixed by the decree. “ In case of refusal to do so, or of failure of execution of the engagement undertaken, it is competent to proceed to expropriation on the ground of public utility, observing the formalities prescribed by the Title II. and those following of the law of 3rd May 1841. “The proprietor expropriated in the execution of this Article has a right to obtain reintegration in his property after the reforesting, on repayment of the expense of the expropriation, and of the works, principal and interest ; or he may relieve himself of repayment of the expense of reboisement by ceding half of the property. “ Art. 8. If the communes or public establishments refuse to execute the works on lands belonging to them, or if it be impossible for them to execute these in whole or in part, the State may do so, either by amicably obtaining possession of the part of the lands which they do not wish, or are unable, to reforest, or by undertaking the whole of the works at its own expense. In the latter case it retains the administration and the use of the reforested lands until the advances made have been reimbursed, principal and interest. But while this is the case, the commune will enjoy the right of pasturage on the reforested lands as soon as the woods shall have been sufficiently protected from injury. ‘Art. 9. The communes and public establishments can, in every case, exonerate themselves from repayment to the State by giving up their right of property in half of the re-wooded lands. This cession of right of property must be made, on pain of forfeiture of privilege, within a period of ten years from the notification of the completion of the works. “ Art. 10. The sowing or replanting in each commune cannot be made on more than on one-twentieth of the extent of the lands annually, unless a resolution of the municipal council authorise the works being carried on on a more extensive scale. 154 LEGISLATION ON TOKRENTS, “ Art, 11. Forest warders of the State may be appointed to the surveil- lance of the sowings and plantations within the boundaries fixed by the Imperial decrees. Offences within these boundaries, proved by these guards, are to be prosecuted as offences committed in the woods subjected to forest régime; and the execution of the sentence is to be enforced conformably to the Articles 209, 211, 212, and to the §§ 1 and 2 of Art. 210 of the Code forestiére. “ Art. 12. The first paragraph of Art. 224 of the Code forestiére is not applicable to reboisements effected with subvention or premium granted by the State in execution of the present law. “The proprietors of lands replanted with woods, with premium or sub- vention of the State, cannot depasture these without a special authority from the Forest Administration, until such time as the woods shall have been recognised by the said Administration as sufficiently protected. “ Art. 13. A regulation by the Public Administration shall determine— (1) the measures to be taken for the determination of the boundary indicated in Article 5 of the present law ; (2) the rules to be observed for the execution and conservation of works of reboisement ; (3) the mode of determining the advances to be made by the State, the proper measures for securing the reimbursement of these, principal and interest, and the rules to be followed for giving up proprietorship of lands which Article 9 authorises communes to cede to the State. “ Art. 14. A sum of 10,000,000 [francs] is appropriated to the payment of expenditure authorised by the present law, to the extent of 1,000,000 per anium. “ The Minister of Finance is authorised to alienate, with power of uprooting if necessary, woods belonging to the State, to the value of 5,000,000 of francs. “These woods cannot be taken except from amongst those entered in table B. annexed to the present law. The alienations may be made successively within a period which shall not exceed’ ten years, reckoning from Ist Jan. 1861. “The Minister of Finance is in like manner authorised to sell the above-mentioned woods to communes on an approved valuation, and on conditions determined by a regulation of the public Administration. “The 5,000,000 of francs, necessary to complete provision for the expenditure authorised by the present law, shall be provided by means of extraordinary fellings of wood, and, if necessary, from the ordinary resources of the budget.” On the same day was enacted a land improvement law, entitled Lot sur la mise en valeur des communaux, providing for the utilization of commons by means of State aid in the drainage, or other measures required to fit for agricultural or sylvicultural operations, uncultivated lands and marshes belonging to communes, or sections of communes, the utilization of which might be deemed beneficial. Under date of 17th August 1860, M. Vicaire, director-general of the Forest Administration, addressed to the Forest Conservators a circular relative to reboisement, of which the following is a translation :— “The question of the replanting of mountains with woods, so important in view of inundations, is about to receive a practical solution. The Tmperial Government, which does not shrink from any expense required to cIncULAR or 177TH aveust 1860, 155 give legitimate satisfaction to the wishes of the country, is of opinion that the time has come to bring to a close the discussions to which this grave question has given rise in scientific societies and in general councils. “ His Excellency the Minister of Finance, faithfully following the Imperial programme of 5th January 1860, has shown, in a remarkable report of the 3rd February following, the necessity of replanting the mountains with woods, and the measures to be adopted to effect this. Shortly thereafter, the Council of State, adopting the views of the minister, presented a projet de lov, which has been adopted, with marked approval, both by the Corps Legislative and by the Senate, after careful consideration. The ardour with which the Legislature of the State has set about realising the generous thought of the Emperor testifies to the greatness of the enterprise, and to the great interest taken in it by the country. “To the Forest Administration is assigned the honour of carrying this into execution, and it will not, I feel assured, come short of its mission. “The mode of execution being to be made the subject of a regulation issued by the public Administration, it becomes of importance that there should be obtained forthwith the data needed for its preparation. I therefore invite you to consider carefully the provisions which it may appear to you it should contain. “ As is the case with all new laws, it may be, the law for the replanting of the mountains with woods will, on its first application, give rise to some difficulties. May I ask of you to consider well those which you may con- sider it likely to give rise to in your district, and to point out to me the best means of removing them. “It cannot be expected that until after the publication of the regulation by the public Administration you should be able to write me fully on this matter. At present, therfore, I limit myself to soliciting your attention to provisions of the law, the execution of which is independent of that regulation, and to measures which should precede the application of the regulations which may be issued. “ Your first endeavour should be to determine the localities in which the work of reboisement will be most useful ; and it should not be allowed to escape your attention that, according to the prescriptions of the law, Government aid should be given exclusively to the replanting of lands situated on the summits or the declivities of mountains. “The Administration cannot extend the resources placed at its command to all the lands which may fulfil these conditions; you should, therefore, endeavour to ascertain to which a preference should be given. In what relates to the works entrusted to your consideration you should avoid making choice, in the commencement of the enterprise, of lands the replanting of which would present an excess of difficulties, that you may not bring the enterprise into contempt, which might result in cooling the zeal of communes and of private landholders. “ You should select as much as may be possible, according to the climate, the nature of the soil, and the exposure of the lands, the kinds of trees of which the successful growth would be most certain, and the propagation of which would be most useful, and prescribe only the culture which would be most suitable for them. “Tt may be it will only be after many trials, which may be like groping in the dark, that you will be able to make your final selection ; and I cannot 156 LEGISLATION ON TORRENTS, too strongly recommend to you to multiply your experimental trials and to make them with all necessary care. “Tt is desirable, for instance, that you should carry on your operations on a great many different spots. “The work of replanting woods can only be carried out successfully if it secure the sympathy of the people of the locality, and nothing likely to secure this should be neglected. “Tt is then necessary that you should make yourself well acquainted with the wants of the communes, and lay yourself out to reconcile with ‘these, as far as possible, the measures to be adopted ; and if present profit cannot be combined with the interests of the future, to sacrifice these ; it is nevertheless necessary to give due consideration to this, and to reckon it a matter of no small importance. “ According to the idea of the Legislature, the encouragements given should be given as much as possible in the form of grants of seed and of plants. “The Administration is already engaged in carrying out drainage and forming sécheries [for the drying of seeds], wherever it is practicable to do so with advantage. “The case of establishing nurseries pertains more especially to you. You will be supplied with all the funds needed to make these in sufficient numbers and under the most favourable conditions. “You cannot give too much attention tu the extension, diffusion, and development of these valuable works, whether they be carried out on account of communes or be executed on account of the State. “ Whenever lands of a certain extent are to be replanted with woods, it will always be found useful to locate one or more nurseries near to these, so as to avoid the risk of failure consequent on too prolonged transport of the plants. : _ “ Article 2 of the law bears, that in the distribution of subventions to communes and public bodies, regard is to be had to their resources, to their sacrifices, and to their wants, and also to the amount granted by the General Councils for reboisement. “The application of this provision will require, on your part, much care, discernment, and tact. “The distribution of subventions will give occasion for the forest officials entering into frequent communication with the representatives of communes and of public bodies; I need scarcely remind you that all your communica- tions should be characterised by the greatest cordiality and amity. “The General Councils will be led to consider whether, in carrying out the views of Government, they ought not to devote a portion of their resources to the work of reboisement. Instructions, which may be necessary to their giving a deliverance on this subject, you should supply without loss of time to the prefects, and, if necessary, take the initiative in communica- tions of this kind. “The law divides itself into two distinct parts, relating severally to encouragement and to coercion ; we have only to do with the first of these here. “The happy results which may be obtained by encouragement may render the application of coercive measures the more rare. This is a _ consideration which should lead you to see that nothing be neglected which at first sight gives assurance of success. STATUTE OF 27TH APRIL 1861. 157 “The whole country will watch with the greatest solicitude the results of the new law. It reckons on your zeal; we must not disappoint the expectation. “JT shall annually report to the Minister the works executed each year, in accordance with the law ; it will be a pleasure to me, in doing so, to make special mention to His Excellency of your zeal, and of that of the agents who shall have best seconded you in this work, which is so important.” The following decree, embodying the statute of the Public Administration for the enforcement of the law of 28th July 1860, was issued 27th April 1861. “Cuap., 1—Or Regorsement Facunratirs, on SaNcTIONED AND AIDED OPERATIONS. “ Arts 1, 2, 8, and 12 of the law of 28th July 1860. “ Art. 1. Proprietors of lands situated on the suramits or the declivities of mountains who desire to avail themselves of the subventions granted by the State, in terms of Arts. 1 and 2 of the law of 28th July 1860, should address their demand to the Forest Conservator. “Tf it be a commune ora public body, the demand should be addressed to the prefect, who will transmit it to the conservator, with a letter of advice. “ Art. 2. Lands belonging to communes or public bodies, on which works of reboisement are undertaken by help of subventions granted by the State, are subjected to the régime forestiére. “The works on these, as well as those of conservation, or of full main- tenance, are to be executed under the control and surveillance of the forest officials. “Tf the lands belong to several communes, and it be necessary to the successful prosecution of the rebowsement that the work be carried on simul- taneously in all of these, there is to be created, conformable to Arts. 70, 71, and 72 of the law of 18th July 1837, a syndic council for the purpose of effecting an execution of the works. “In case of the non-execution, or of the bad execution, of the works certified by the forest officials, the prefect passes a resolution enjoining the restitution to the State of the subventions which have been allowed. « Art, 3. Premiums in money, obtained by private proprietors after the execution of the works, are to be paid on presentation of a minute of acceptance of works, drawn up by the local forest official in the form of minutes of acceptance of works of improvement in the State forests, and on the advice of the inspector and the conservator. “ Subventions in seeds, or in plants, delivered to private proprietors before the execution of the works, are to be ‘estimated at their money value. The valuation is to be notified to the proprietor, and accepted by him. The amount of this is to be repaid to the State in case of the non-execution of the works, the misappropriation of the seeds or plants, or of the bad execu- tion of the work certified, as has been prescribed in Art. 2 of the present regulations. “Art. 4, The allocation of subventions exceeding in amount 500 francs is to be made by the Minister of Finance ; the allocation of subventions under 500 francs in amount is to be made by the Director-General of Forests. “Art. 5. When works of replanting have been executed on lands belonging to private proprietors by help of subventions, the proprietors, 158 LEGISLATION ON TORRENTS. before admitting cattle into the plantation, must address an application for permission to do so to the conservator, who is to cause the state of the young woods to be ascertained by the forest official, and to determine accordingly, under power of appeal to the Minister of Finance. “Tf the proprietor fail to conform himself to the decision given, the whole or part of the subventions granted may be charged against the proprietor, “ Cuap. [].—Or REBoISEMENTS OBLIGATOIRES, OR ENJOINED REPLANTINGS. “ The determination of the boundaries within which it is necessary to execute the reboisement. “ Act. 6. When the Forest Administration considers that it is proper to pro- ceed to determine the boundaries of the lands on which it is necessary to execute works of reboisement, the Director-General of Forests is to give notice to the prefect of the forest agents designated for the preparation of the minute of specification of the lands, the diagram, or plan of the places, and the pro- posed project of the works to be executed. “The prefect is to designate the engineer of roads and bridges, or of mines, whose consent to the operation is required. “ Art. 7. The minute of specifications is to be accompanied by a descrip- tive memoir, indicating the object of the enterprise, and the benefits expected to attend it. “The diagram, or plan of the place, is to be prepared in accordance with the land-register of the district. It is to indicate, in regard to each plot, the number specifying it in that register; the superficial contents; the name of the proprietor ; and if it belong to a commune, or to a public body, the sum total of the superficial contents of lands belonging to the commune, or to the public body. “The project of works to be executed is to indicate the lands which it is designed to replant ; it fixes the time within which the works should be executed ; and it contains (1) an approximate estimate of the expense, and a project of the partition of this expense among the different proprietors ; (2) an indication of the subventions which might be offered to each pro- prietor ; (3) a valuation of the actual revenue from each lot, of the value of the ground, and of the value of the crop ; (4) any other statistical informa- tion which might be useful, if known. “Art, 8, The documents spoken of in the preceding Article are to be addressed by the Forest Administration to the prefect, who is to proceed to institute in each commune the inquest prescribed by Art. 5 of the law of 28th July 1860. “The project of operations is to remain deposited in the mayor’s office for a month ; at the expiry of this time a commissioner, designated by the prefect, is to receive, at the mayor’s office, during three successive days, declarations from inhabitiants regarding the public utility of the projected works. These days are reckoned from the advertisement, given by means of publication, and posted notices. The authority for such advertisement, and the publication of the order of the prefect which appoints the opening of the inquest, must be a certificate from the mayor. : “After having closed and signed the register of the declarations, the commissioner is to transmit this immediately to the prefect, with advice, and the other documents of instruction which have served as a ground for the inquest, STATUTE OF 27TH ApRit 1861, 153 “ Art. 9. The Municipal Council of each commune concerned, summoned for the purpose by injunction from the prefect, is to examine the documents in question, and, after a delay of a month, to give its opinion by a resolution adopted in conjunction with the prescribed addition of others, equal in number to that of the officiating members of the municipal council. This resolution is to declare, if such be the case, whether the municipal council authorises the works of replanting to be carried out to a still greater extent than that specified by Art. 10 of law of 28th July 1860. The minute of this resolution is to be added to the documents connected with the inquest. “Art. 10. The commission instituted by the second paragraph of Art. 5 of the law of 28th July 1860 is formed by the prefect in each of the depart- ments traversed by the line of works. “ This commission meets at the place indicated by the prefectoral resolu- tion, and on the fifteenth day from the date of that decree. It examines the documents giving the requisite instructions, and the declarations delivered to the registrar of the inquest ; and, after having deliberated on these in company with any persons whom they may consider it would be well to consult, and with the information which they consider necessary, they give their opinion both on the utility of the undertaking, and on the various questions submitted by the Administration. “These different proceedings, of which a minute is to be prepared, must be completed within another period of one month. “ Art. 11. The prefect, after having taken the opinions of the Council of the Arrondissement and of the General Council, is to forward all the docu- ments relative to the case, together with his own opinion, to the Minister of Finance, who, after having previously consulted with the Minister of Agriculture, of Commerce, and of Public Works, and the Minister of the Interior, if there be occasion for it, is to submit to us his report. “A deliverance will then be given by us on the question of the public utility of the works, our Council of State having heard the case. “ Art. 12. A duplicate of the decree which declares the public utility of the works is to be transmitted by the Director-General of Forests to the prefect, who is charged with the fulfilment of the formalities prescribed by Art. 6 of the law of 28th July 1860. “ At the same time the Forest Administration is to notify to the prefect, in regard to each plot in the register, the works to be accomplished, the conditions under which they are to be executed, and the time within which this must be done, the offers of subvention made by the Administration, and the advances of money to which they are prepared to consent. “Cap. I[].—Or toe Execution anD MAINTENANCE OF THE WORKS. “Cap. 1.—Lands belonging to priate proprietors comprised within the boundaries specified by the decretal declarative of public utility. é “ Art. 13. Within a period of one month reckoned from the notification which is made to him of the decreet declarative of the public utility, the private proprietor of the lands comprised within the boundary shall declare whether he intends to execute the works himself, or to give up the execu- tion of them to the Forest Administration. “This declaration is to be made in duplicate, and transmitted to the sub-prefecture of the locality in which the places are situated, or in which 160 LEGISLATION ON TORRENTS, they are registered. These duplicate declarations are revised by the sub- prefect, who is to return one to the party by whom the declaration is made, and to transmit the other immediately to the prefect. “Tf the private proprietor wishes to execute the works himself, his declaration is to contain, in addition, proof of his possessing means of doing so. ‘‘ Art. 14, Failing the deliverance of this declaration, the private proprietor is to be held to have refused to undertake the works at his own expense. “ Art. 15, The works executed by the private proprietor, with or without subvention, are to be subject to the surveillance of the Forest Adminis- tration. “ Art. 16. The Forest Administration is to proceed to the execution of the works to be carried on on the lands of the expropriated proprietors. “The completion of the works is to be notified by the Forest Adminis- tration to the expropriated proprietor. The notification is to contain, moreover,—(1) a detailed account of the amount, principal and interest, of the cost of the works executed from the period of expropriation ; (2) an estimate of the annual expenditure deemed necessary for the con- servation and maintenance of them. : “ Art. 17. When, in accordance with Act. 7 of the law of 28th July 1860 the expropriated proprietor wishes to avail himself of the right to obtain reintegration, he is to make the declaration to the sub-prefecture within the five years following the notification made to him, in terms of the preceding article, and to notify in this deed whether he intends to obtain his reintegra- tion by reimbursing to the State the advances made, or by giving up to the State a half of the property. “ These declarations are to be registered, and of thisa certificateisto begiven. “ Art. 18. If the proprietor makes choice of reimbursing the advances made by the State, he is to produce, in support of his declarations, the necessary proof that he is in circumstances to reimburse the indemnity of expropriation, and the expense of the works, both in their first establishment and their maintenance—principal and interest. “This declaration and documents in support of it are to be addressed within a month to the Minister of Finance, who is to decree and determine the forms, and the time within which the proprietor shall be reintegrated. “ Art. 19. If the proprietor offers to give up to the State one-half of the property, proceedings are to be taken by a forest agent, and by the pro- prietor, or his delegate, to divide the land into two lots of equal value. “Tn case of dispute in regard to the formation of these lots, it is to be determined by a third party, a skilled umpire, named by the president of the tribunal. “The appropriation of the lots is to be determined by drawing of lots, if the parties cannot come to an amicable arrangement. “Tf a part of the works has been executed by the proprietor, this is to be taken into account in making the division, by a proportional deduction being made from the lot which falls to the possession of the State. “CHap. 2.—Lands belonging to communes or to public bodies comprised within the boundary specified by the decretals declarative of public utility. “Sgor. lst.—The execution of works to be carried on on the lands belonging to communes or public bodies, “ Art. 20. Within a month from the date of the decreet declarative of STATUTH OF 277TH APRIL 1861, 161 public utility, communes and public bodies, proprietors of lands, comprised within the boundary, are to notify to the prefect, by an explanatory declara- tion, whether their intention be to execute the works with their own resources, in whole or in part, on the prescribed conditions ; or to leave to the State the care of charging itself with the works, at its own expense, subject to reimbursement ; or, in fine, amicably to cede to the State, in whole or in part, lands belonging to them comprised within the boundary. “ Failing the communes or public bodies notifying their intentions within the period stated, the State is to undertake the works at its own charge, conformably to the provisions of Art. 8 of the law of 28th July 1860. “Art, 21. Lands belonging to communes or to public bodies, comprised within the boundary specified by the decreet declarative of public utility, are to be subject absolutely to the régime forestiére. “ Art, 22. When the commune or the public body shall have notified its intention to execute the works, the Municipal Council, or the Administra- tive Commission, is to grant each year the funds judged necessary for the execution of new works, and for the maintenance of works accomplished. “Art, 23. The execution of the works is to take place under the surveillance of the forest agents. “In case of non-execution, or of bad execution, certified by the conserva- tor, a decision by the Minister of Finance is to ordain, if the measure be proper, that the State shall undertake the work at its own charge, in terms of Art. 8. of the law of 28th July 1860. “When the lands belong to several communes, and the successful prosecution of reboisement requires the works to be carried on together, there is to be created, if all the Municipal Councils charge themselves with the undertaking, a syndical commission for the prosecution of the execution of the works, conformably to Arts. 70, 71, and 72 of the law of July 18, 1837. “Sror, 2np.—Determination of the advances made by the State to communes or to public bodies, and measures proper to secure the reimbursement of these. “ Art. 24, When the communes or public establishments decide to leave the works to the charge of the State, the Forest Administration is to cause them to be executed in accordance with the forms used in the matter of works of amelioration in the forests of the State. “The statements of expenses are to be prepared conformably to the rules of office accounts in the Forest Administration. “In the same forms are to be prepared the statement of annual expenses of maintenance. “ Art. 25. Ifthe works concern several communes, the partition of the expense is to be made according to the form required by Art. 72 of the law of 28th July 1837. “Every year there is to be delivered to each of the parties interested a statement of the expenses incurred on account of the party by the Administration. “ After the completion of the works, an account-general of the expendi- ture is to be ordered by the Minister of Finance, and a copy is to be delivered to each of the parties interested. “The sums forming the amount of this account, and constituting principal, are to bear a charge of simple interest at 5 per cent. from the completion of the works. i “Art, 26, The works effected by the State are to be maintained by the 8 162 LEGISLATION ON TORRENTS, care of the Forest Administration. The advances of the State for this object, ordered each year by the Minister of Finance, are to bear interest at 5 per cent. per annum. “A copy of the account is to be delivered to the parties concerned, along with the statement of the expenses previously incurred. « Art, 27. Demands of revision or rectification of the annual accounts of the expenses of the establishment, or of the maintenance of the works, should, on pain of forfeiture of right to these, be brought before the Councils of Prefecture within six months of the notification of said accounts. After that’time the accounts become fixed. “ Art, 28. The accounts of these products, and that of the expenses, are to be made out and approved each year by the Minister of Finance, and a copy is to be certified to the parties concerned. Within six months after this notification the parties concerned can, as in the case of the account of works, make the demand indicated in the preceding article. “The value of these products is to be deducted from the interest due to the State, or otherwise, in the next place, from the principal constituted by the expenses incurred in the establishment and the maintenance of the works. “ Art. 29, When the State is entirely reimbursed, the advances made by it—be it by products gathered by it, or be it by payments made by the parties concerned—these are forthwith to be put again in possession of the lands administered for them by the State, under such reservations as result from their being subjected to the régime forestiére. Snot. 3np.—Rules to be followed in giving up of lands which Art. 9 of the aw of 28th July 1860 authorises communes to cede to the State. “ Art. 30. If the commune, or the public body, relieve themselves of all repayment by ceding a half of the lands replanted, the Municipal Council of the Administrative Commissions is to adopt a resolution to this effect, which is to be notified to the prefect within the period indicated by the second paragraph of Art. 9 of the law of 20th July 1860. “ Art. 31. Proceedings are forthwith to be taken by a skilled person nominated by the prefect, and a Forest Agent designated by the Forest Administration, to divide the same into two lots of equal value. “The appropriation of the lots is to take place by drawing of lots, if the parties concerned cannot come to an amicable arrangement of this. This proceeding is to take place in the presence of the sub-prefect of the Arrondissement. “Tf a part of the works has been executed by the commune or the public body, this is to be taken into account in the division, and a proportionate reduction is to be made in the share which falls to the lot of the State. “ CHap. 3.—General directions. “Art. 32. Before commencing the works within the extent of the boundaries fixed by the Imperial decrees, there is to be made, at the expense of the State, a determination of the boundaries, and, if need be, a marking off of the said boundaries on the ground.” In order that the superior local officers of the Forest Administration might be fully acquainted with what it was desired should be done in the carrying out of the decree, the Director-General of the Forest Administration, CIRCULAR OF 1st suNE 1861. 163 M. Vicaire, subsequently issued the following explanations, in a circular addressed to forest conservators, under date of Ist June 1861 :— “Part J.—REBOISEMENTS FacuLTaTirs, OR SANCTIONED AND AIDED OPERATIONS. “The Ist Article traces out the course to be followed by private pro- prietors, the communes, or the public establishments, in the applications for aid that they may have to make. By the terms of Art. 2 of the law of 28th July 1860, the aid in the reforesting of the lands situated on the summits or the slopes of mountains is granted on account of the utility of the work as regards the general good, having respect, in reference to the communes and the public establishments, to their resources, their sacrifices, and their need, as well as to the sums allotted by the General Councils for , reforesting. The communes, whose territory is situated in the regions where the reboisement of the mountains is in the highest degree important to the public good are in general very poor, and often they have no other resources than what they derive from pasturage. Every reduction in the extent of the lands free to all excites among the inhabitants of these regions great appre- hension. Great efforts in the initiative could not, therefore, be expected from them, and it is better in such cases to be lavish with encouragement. The Government will contribute very largely to the expense of the work, whenever the communes placed in these circumstances show their good- will to the work. ‘ “When, on the other hand, the lands belong to proprietors more advan- tageously situated in regard to pecuniary resources, it is better to be less ready in giving aid, and to apportion this more strictly to the efforts and sacrifices of the proprietors. “The law for the reboisement of mountains is essentially a law of general interest, and it is in this point of view that it is necessary to regard it in considering the demands for aid. ‘‘ With a view to securing proper order and regularity in the consideration of such demands, they ought to be given in before the 15th of July of the year previous to that in which the aid is required. Those which arrive subsequently to that time will be carried over to the next year, excepting, however, cases in which you may decide that it is better to proceed without delay to the decision. The requests will be summed up in the form of ordinary reconnaissances, and must reach the Government before the 1st of September, with your observations and information, at the same time with the accounts of the demands for seeds which you annually furnish for re- sowing void places in the Government forests. It is not necessary to say that the rule in regard to this can only be followed out when the demands for aid shall have been established in an orderly manner. The demands which reach you this year, or at the commencement of the next, will be attended to with the least possible delay. “It is necessary to take every precaution to insure the proper application of the aid. ‘To this effect the demands should be made out upon formulas, conformed to the models 1 and 2 hereto annexed. Notice should be given of the granting of the aid, in the form of models Nos. 3, 4, 5, and 6. As you will see, these different formulas have been arranged so as to make known to the parties for whom the aid is destined the obligations to which they are subjected, and at the same time to give to the Government the right of exercising, in case of need, its right to reimbursement, 164 LEGISLATION ON TORRENTS, “ The preceding directions are only applicable to the authorised replanting of woods for which demands for aid may in future be sent in. The works already undertaken, by the help of credit placed at your disposal upon the ‘fund appropriated to the expenses of the replanting of the mountains with woods, will be continued according to the plan on which they were commenced. “‘ Article 2 relates to the work to be done in the lands belonging to the communes, or to the public establishments. These lands being by clear title subject to the forest department, it will not be necessary to get for them special applications ; it will suffice that you address to the Administra- tion, at a fit opportunity, the necessary instructions, in order that they may be inscribed upon the roll of the communal woods or public establishments subject to the Forest Administration. “‘ When there may be occasion to form a municipal commission, you will “make known to the Government the measures taken to this effect. Aid will only be granted when the said commission shall have been regularly constituted, “You will take care that the control and supervision of works by the forest agents shall be efficiently maintained. “The aids for the execution of works of reforesting on lands belonging to private proprietors are principally granted in kind. But aid in money can be granted to private proprietors under the head of money advanced, The exposée des motifs, or explanation of the grounds of the law of 28th July 1860, says, on this subject, that the private proprietors themselves shall be admitted to the benefit of aid in money, at least in certain exceptional cases, where the actual expense would be too great compared with the profits, necessarly remote, and in which the work should present a character of public utility sufficiently obvious in order to its appearing just on the part of the State to support outlays, of which the public would in part reap the fruit, “ When a private proprietor shall have framed a request, the same form will be followed as in the demand for aid in kind. The agents will visit the localities, certify the state of the property, appraise the expenses of the work, as well as their utility in regard to the public interest, and estimate, principally as regards the latter point, the amount of aid to be allowed, ‘“‘The third Article traces the course to be pursued in the payment of this, “ As regards the payments in kind, the model formula No 3, has been so prepared that the deed of notification forms, between the Adminstration and the receiver of the aid, a contract of akind supplying a reciprocal guarantee on behalf of the subsidised proprietor, and on behalf of the general interest. * Articles 4 and 5 have no need of explanation. “When the staff of agents and employés of the ordinary service shall be acknowledged to be insufficient to insure the execution of measures relative - to the replanting of woods, further measures must be taken for this object. Already, at a certain number of points, posts of brigadiers and warders have been created for this special object. I recommend to you to see that the persons appointed to these posts shall render all the services rightly required of them. ‘Part I],—REBOISEMENTS OBLIGATOIRES, OR ENJOINED OPERATIONS. “ Specification of the boundaries of the lands on which tt is necessary that reborsement be effected, “ Article 6 gives to the Administration of Forests the charge of marking out the lands on which it is necessary to execute the work of rebosement. CIRCULAR OF Ist sun» 1861. 165 “ Of all the measures which are prescribed for the execution of the law of the 28th July 1860, there are none to refer to which is more important than the marking out of these. I call your special attention to this point. The object of the law is the protection of the soil against the ravages of inunda- tions, and the falling away of the slopes. In order that the work of reboise- ment toay have any efficacy as tegards hydraulic results, and the retention of the soil, it is indispensable that they should not be limited to scattered points. The overflow of the water-courses during storms or heavy rains is caused, as you know, by the sudden flowing in of the waters into the beds of rivers and torrents, These water-courses are formed by the union of the streams, more or less considerable, which rise in the bosom of the mountains. If the surface of the inclines where the streams rise were properly clothed with vegetation, the water, restrained on all sides in its progress, would flow without violence into the bed of the river, which would only overflow in those rare and exceptional circumstances, in which occur great meteorological phenomena, against which all obstacles are powerless. “ By an analogous operation the presence of vegetation on the surface of an incline prevents its falling away, by dividing the lesser courses of water and preventing their augmentation. According to these considerations, which I cannot avoid mentioning here, but which your experience of moun- tainous regions must enable you to appreciate, you will understand that the consideration of the lands on which it is necessary to undertake such works, ought, with a view to securing the important result desired, to be directed to both of these aspects of the effects anticipated. “In every case the operation must be determined by circumstances relating it may be to the water-courses, or relating it may be to the moun- tain declivity ; and it will be for you to judge and decide at what point it is most urgently required that a commencement should be made. * Article 6 bears that ‘the Director General of Forests shall make known to the prefect the forest agents designated to prepare the report on the character and condition of the lands, the chart of the localities, and the specification of the works proposed.’ “The operations must be carried on in general by special agents, who shall enjoy the same advantages as the agents composing the Commissioners of the Cantonment, or of Management of Forests. “The forest agent shall have for associate the engineer of roads and bridges, or of the mines, designated by the prefect. I do not require to recommend to the agents of the Forest Administration to maintain in their relations with the agents of the Administration of roads and bridges, or of mines, the spirit of cordial co-operation which ought to animate all the functionaries of the State in their common efforts for the advancement of the public interest. “Art. 7, The report of the inspector, the descriptive memoir, the plan of the localities, and the scheme of projected works, form conjointly and exclu- sively the basis of operations. In terms of article 5th of the law of 28th July 1860, this work, first submitted for examination for a month, during which period all parties interested may become acquainted with it, and then presented for the discussion of the Municipal Councils, is to be examined in succession by a special commission, by the Council of the Arrondissement, and by the General Council. It is not until after the Ministry of Agricul- ture, of Commerce, and of Public Works, and the Ministry of the Interior, if such there be, have been consulted that the Ministry of Finances is to 166 LHGISLATION ON TORRENTS, submit it to the Emperor the order to be issued, the Council of State having been heard on the question of the public utility of the works. It is of importance then that the work be prepared with due care, and contain suffi- cient indications, that in passing through this long process of examination no considerable element of defect may appear. “T cannot prescribe any determined form to be followed in these docu- ments, the instructions which would be necessary would vary with the special circumstances of each country. “Tt would be, besides, premature to lay down at the outset of an operation regulations so important, which experience had given no opportunity of ratifying. I leave to the agents to consider, under your direction and in concert with the engineers, what may be the most convenient manner of presenting the different elements of the work. I consider, however, that I ought to address to you on this subject some general observations. “ T have stated to you above the considerations in accordance with which ought to be carried out the inspection of the lands which it is necessary to cover with vegetation, to accomplish the object of the law on the reboise- ment of the mountains. Amongst these lands, doubtless, many, through their state of complete denudation, cannot be converted immediately into what can properly be called woods, The agents ought to make known by what preparation, be it by putting them totally or partially under enclosure for a time more or less prolonged, or be it that by the natural or artificial production of vegetation of any inferior kind, they may be rendered fit for the reception of seeds or of plantations. This indispensable preparation comes directly within the range of the works of reboisement, “There are also lands which by reason of their situation appear naturally destined for use as pasturage. The conversion of these lands into woods would be of no utility, as preserved in the condition of pasturage they ren- der to the inhabitants the least expensive and best services possible in what therein concerns the general interest, and the maintenance of these pasturages in good condition suffices in many cases to retain the water, and the land, The scheme of operation ought then to divide the lands into three classes, namely,—(1) Those in which we may proceed immediately to direct works of reborsement ; (2) those in which these works ought to be preceded by a natural or artificial preparation ; (3) in fine, those which ought to be left free for the growth of pasturage, subject to appropriate regula- tions. The two first classes alone are subject to the application of the law of 28th July 1860, on seboisement. “Tt will suffice to indicate in regard to lands of the third category, the regulations to which it would be well to subject the exercise of pasturage, “Tn relation to the subvention which might be offered to each proprietor for the execution of the works within the prescribed limits required by public utility, you have only to take into account the resources of the parties interested, their requirements, the sacrifices which they are disposed to make, and the amount of the sums allocated by the General Council. “ Article 10, of 28th July 1860, bears, ‘that the sowings or plantations cannot be made annually in each commune over more than the twentieth part at most of the area of these lands, unless a decision of the Municipal Council authorise works over a more considerable extent,’ “When an area surveyed comprises more than the twentieth of the lands belonging to a commune, if this commune refuse to allow the execution of works over a more extended area, it will be well to select and indicate the CIRCULAR OF Ist suNE 1861. 167 portion of the lands on which it will be of most utility to execute these works. “ Article 8 indicates the manner in which ought to be conducted the examination prescribed by article 5 of the law of 28th July 1860. Measures to this effect are to be taken by the prefect, when he is supplied by the Administration of Forest with the papers enumerated in article 7. You will address these papers to the Administration when the work for any one complete undertaking shall be finished, whatever may be the importance of the work, be it for a water-course from a river, from a secondary affluent, or even from a torrent, or, what’ is better still, be it for a mountain declivity. “ Articles 9, 10,11, and 12 require no explanation. I shall only call your attention to the institution of the commission, of which article 10 de- fines the powers. According to the terms of section 2 of article 5 of the law of 28th July 1860, it is required that one member of that commission shall be a forest agent. You will understand the necessity of not desig- nating to the prefect for that important mission any but an agent capable of worthily representing the Administration, if you do not judge it proper to reserve it for yourself, because of the interest attaching to the projected works. “ Parr [1].—Or tae EXECUTION AND OF THE MAINTENANCE OF THE WORKS. “Cuap. 1.—Lands belonging to private proprietors, comprised within the boundaries specified by the decree declarative of public utility. “The Administration will forward to the prefects, with the documents mentioned in section 2nd of article 12, formulas in accordance with the models Nos. 9 and 10, hereto annexed, in order that they may be enabled to furnish particulars, at the same time calling their attention, in accor- dance with section 2nd of article 6 of the law of 28th July 1860, to the extract of the Imperial decree, containing the indications relative to the lands belonging to them. “ Article 13 gives to private proprietors the option of undertaking the immediate execution of the works under their own superintendence, and at their own expense, with the subventions granted by the State, if there be any, or of giving up to the State the execution of the said works. “In the first case, advice must be given to the party interested of the allocation of the subvention in the formulas 8 and 9 hereto annexed. “ According to the terms of paragraph 4th of article 13, the private proprietor who wishes himself to execute the works ought to give proof of his possession of the means of doing so. The public interest being sufficiently protected by the power given to the State by article 7 of the law of 28th July 1860, to recover by expropriation of the property, in case of non-fulfilment of the engagement made, there is no occasion to be offensively exacting in requiring the production of such proof. A declara- tion from the mayor of the commune, agreeably to the indications borne by the form No. 7, it appears to me, may be considered in most cases a sufficient guarantee. “‘ When the private proprietor has declared his intention to give up the execution of the works to the State, it is done by the Administration in the same form as that for the communal lands and those of public establish- ments, in which the State proceeds directly to the works; and the re-entry on 168 LEGISLATION ON TORRENTS, possession of the said private proprietor takes place according to the same mode, and on the same conditions. “The operation is considered an amicable one between the State and the party interested, and is not to take the legal form of expropriation, excepting in cases of disagreement. ' & Articles 14 and 15 require no explanation. “ Articles 16, 17, 18, and 19 detail the course to be followed in case of expropriation, in terms of sec. 3, 4, and 5 of article 7 of the law of 28th July 1860. It is but very rarely that there will be occasion to have recourse to this measure. The exposition of the motives of the law on reboisement bears, in regard to this subject, ‘ That this exceptional remedy of the expropriation of private property shall be a rare and exceptional appliance.’ It has not been without great reluctance and repugnance that the legislative body has consented to introduce into our code a new case of expropriation. “ When the Administration shall meet with a refusal, or with an insufii- ciency of resources of a private proprietor for the execution of the works, and all attempts at persuasion, and all the offers of subvention, have come to nought, against a declared opposition, or an absolute inability, it will become necessary to have recourse to expropriation, But every time that this shall occur you shall refer to the Administration, which will address to you timeously the instructions of which you have need. It will consequently . ke of no advantage to indicate here general rules in relation to this, “Qnap, 3.—Lands belonging to communes or public bodies, comprised within the boundaries specified by the decretals declarative of public utility. “ Szotion 1.—The execution of works to be carried on on such lands. “The Administration will address to the prefects the documents mentioned in 2nd section of article 12 of the decree of 27th April last, formulas conformable to the forms 11, 14, and 15 hereto annexed, in order that they may be able to transmit them to the Municipal Councils, or to the Administrative Commissions, directing their attention, in execution of the arrangements of par. 2nd of article 6 of the law of 28th July 1860, to the extract of the Imperial decree containing the indications relative to the Jands which belong to them. “Art. 20 indicates three different courses which may be followed in carrying out the work on communal lands, or the lands of public establish- ments within the limits. The commune, or public establishment, which does not wish to submit the whole of its lands to the same régime, ought to make as many special declarations as,this land contains of portions destined to have a different course adopted in the execution of the work upon it. “In case of allocation of a subvention, advice is to be given to the party interested, according to the forms Nos. 12 and 13. “The amicable cession to the State of communal lands, or the lands of public establishments, in terms of the article 8 of the law of 28th July 1860, will present in many cases great advantages. On one hand the State will thus find facilities resulting from the suppression of pasturages, and from exclusive direction, without disputes in regard to the works; on the other hand, poor communes will thus have the means of deriving advantage from Jands which procure for them at present only insignificant resources, and of Which the reboigement would entail expenses which perhaps they would never be able to reimburse, | CIROULAR OF Ist JUNE 1861. 169 “Tn such cases you should use all your influence with the Municipal Councils, and call in that of the prefect to induce them to treat amicably with the State. “ Communal lands, or the lands of public establishments within the limits, being subjected absolutely to the forest régime, in terms of Article 21, it will suffice that you address to the Administration, at the proper time, the infor- mation necessary to have those lands inscribed among the communal woods, or the woods of public establishments subjected to the forest régime. “ Articles 22 and 23 need no explanation. ‘“‘Szotion 2.—Specifications of the advances made by the State to the communes, or to the public bodies, and measures proper to secure the re- imbursement of these : “Works at the expense of the State on lands belonging to communes and to public establishments differ in nothing from the works carried on by the Forest Administration on the grounds belonging to-the State. The agents directly superintend and maintain these works, without any intervention of the Municipal Councils, or of the Administrative Commissions. “ It is only required to keep a separate account of the expenses relative to each commune, or to each public establishment, up to the time when the State being completely reimbursed the advances made to the commune, or to the public establishment, they re-enter on possession of the lands subject to the forest régime. “ There will be sent to you timeously, if there be need, more detailed instructions for the keeping of this account, and for the annual notification to the parties interested of the expenses incurred on their behalf by the Administration. “ Sgotion 3.—Rules to be followed in the giving up of lands which Art. 9 of the law of 28th July 1860 authorises communes to cede to the State : “Tn terms of Art. 9 of the law of 28th July 1860, the communes and the public establisments may, in any case, relieve themselves of repayment to the State by ceding the proprietorship of half of the lands re-wooded. “ Articles 30 and 31 of the decree of 27th April 1861 prescribe the course to be followed in such a case. “ The execution of these dispositions ought not to take place but in a future pretty distant. I reserve to myself to give to you, in good time, the instructions which you may then require, “ Coap. 4—General Directions. “ Art, 32. It is necessary that the bounds of the lands comprised within the limits fixed by the Imperial decrees should be determined in such a manner as to prevent all subsequent dispute, This end may doubtless be attained in both cases without its being necessary to proceed very stringently to work. : “Tn order to avoid long delays, and the expense inseparable from such, it will almost always suffice to proceed to a conjoint reconoissance in a manner almost analogous to that of the partial determination of boundaries, “The deeds concerning the communes and the public establishments are neither subject to the formality of official seal nor to that of registration. “In what relates to private proprietors, the demand for subvention, like T 170 LEGISLATION ON TORRENTS, as do all petitions, requires the official seal. The petitioners are authorised, by express exception, on paying ready money, to get the official seal applied to those formulas, either before or after the examination of the demand, provided in every case that this be before the despatch of the document to the conservator. In regard to deeds, entitled ‘Advice of allocation of a subvention,’ copies are exempt from seal and registration. Despatches which shall be delivered otherwise than to the public functionaries, for the service of the Administration, and with notice of this destination, must be written on stamped paper at 1 franc 25 cents per sheet. “The instructions which I have just given you for the execution of the principal arrangements of the law on the reboisement of the mountains may possibly prove incomplete. If the preceding explanations do not appear to you sufficient, I shall supplement them by special instructions. “The season being already very much advanced it is of impoitance to set to work immediately. The watchmen belonging to the State or to communes, on duty in the districts where the works are carried on, shall be put at the disposal of the agents whenever you judge this to be necessary. These overseers, by reason of their knowledge of the localities, will be for the material portion of the works very useful auxiliaries. “When the number of the overseers shall be insufficient, you can pro- pose to create for the object to which it refers the special employment of watchmen, or of brigadiers, who shall be ultimately appointed to the over- sight of the sowings and plantations, in terms of article 11 of the law of 28th July 1860, , “T have already had occasion to point out to you the great importance which the Administration attaches to the work of reboisement. I shall not insist on this matter. “The agents and the overseers who take part in the works in an active and useful way shall acquire special titles at the good pleasure of the Administration. Every time also that the work of reboisement, whatever be its nature, shall occasf6n to them extraordinary fatigue or expense, there shall be allowed to them either in the form of special indemnity, or in the form of an annual gratuity, a remuneration proportionate to the burdens borne and to the services rendered. ; “Tn order to keep the Administration acquainted with the progress of the works, you should cause to be sent to them, in the months of July and January, statements in the forms Nos. 16 and 17 hereto annexed, in which shall be given information relative to the works done during the preceding half-year.” It has not been deemed necessary to append the schedules referred to, ‘It may have been observed that care was taken not to run counter to the Prejudices and feelings of those who were likely to be benefited more im- Mediately by the operations proposed ; and by a ministerial decision of the 21st November 1861, there were instituted annual conferences of the agents employed in the superintendence and execution of the works of reboisement. The following is a réswmé of the first of these conferences which was held on the 9th, 10th, and 11th of December of that year, at Valence, for the region of the Alps ; at Aurillac, for the region of the mountains of Central France j and at Tarbes, for the region of the Pyrenees. There are stated the questions discussed, and the annotations of the Administration, the whole being arranged under different headings, RESUME OF CONFERENCES 1N 186], 171, Résumi, ETO. :— “ DISPOSITIONS MANIFESTED BY THE POPULATION OF THH DIFFERENT DISTRICTS, __ ©The inhabitants of the mountains, chiefly preoccupied with the interest of pasturage, do not welcome in general, but with a certain apprehension, any measures relative to reboisement. Nevertheless, the personal proceed- ings of the agents, with the concurrence of the prefectoral authority, have already overcome much of the resistance of the Municipal Councils, In many departments, amongst which may be cited the Cantal, l’Aridge, Vancluse, a good many of the communes have voted subventions for the replenishment of denuded mountain lands belonging to them. In the Arrondissement of Saint-Girons seventeen communes, according to the specifications of the inspector, have given up in 1860 and in 1861 either the “twentieth part of the price of the fellings sold, or the proceeds of damages, or amends pronounced by the civil courts in their favour, to be employed in works of reboisement. There has been occasion to remark that on many points the mass of the population is favourable to the operation, and that resistance is offered only by some more or less influential members of the local Administrations having a personal interest in securing that the pasture lands be not diminished. ; “There is reason also to acknowledge that the rapidity of the success of the works has had the good effect of bringing the communes to enter into the scheme of reboisements. This result has been notably the case in the Puy-de-Déme, where important works of reboisement have been com- pleted for some years, and where the Administration meets now but rarely with opposition, and this opposition is overcome without difficulty. “ As for private parties, they hesitate generally to undertake works of reboisement, the fruits of which they can only reap after long delay. They dread the expense of the works, and the difficulties of surveillance, and they are kept back by their ignorance of what means to employ to accomplish conveniently the replenishments. A great many of them, more especially in the Loire, have manifested a desire to see the direction of works of reboisement on their properties entrusted to the agents of the Forest Administration, and the example in this matter is found to be contagious. The fact has been established in the Ardéche, where some private parties, having made demands for subventions on the invitation of the forest agents, have been speedily followed by many proprietors. The number of demands of this kind in the department in question has risen to no less than 365 in 1861. “ REMARKS.—The report given of the state of mind in the mountainous regions, relative to reboisement, indicates the means to be employed to enlist the sympathies of the population in the operations, To multiply the personal proceedings,—to make a good selection of ground for first experiments, in order to arrest the eye, and to con- vince the indifferent and the incredulous,—to call in the conjoint action of the prefectoral authority at all times when resistance, re- sulting from personal interest, is shown in the Municipal Councils— such are the general means which may be employed by the agents, The Administration on its part will support their proceedings, and will be liberal in encouragement whenever the general interest may appear to demand the powerful concurrence of the State. “To act on such minds too much cannot be done to diffuse information of the advantages realized by reboisement. The commune of Bourg, 172 LEGISLATION ON TORRENTS, Lastic, in the Puy-de-Déme, possessed a piece of ground of 64 hectares, covered with heaths, which they could not dispose of in 1834 at the price of 7,000 francs. At this time a sowing of the ground with Scotch firs was undertaken, at the expense of the commune, with the assistance of the departmental treasury. The expense was not great. To-day the ground is valued at 70,000 francs, and the commune begins to obtain from it products which in a few years will be very considerable. The commune of Durtol, in the same department, possessed a wood of 47 hectares, planted with Scotch fir some fifteen or seventeen years before, in which they have lately carried out a thinning which has brought into the communal chest a sum of nearly 16,000 francs. Such cases are of a character to remove hesitation. “ As regards private proprietors, the applications for subventions, which have been made successively in the Ardéche, are an indication of what will occur, most likely, everywhere where the bite has been given. The Administration will agree, moreover, to cause the works of reboisement to be directed and superintended by its agents or by special overseers, whenever a certain number of private proprietors, resident in the same district, shall express a desire for this, and the measure shall appear necessary to the success of the works, aud to their development. “ REBOISEMENTS F'ACULTATIFS, OR SANCTIONED REBOISEMENTS. “The opinion was expressed that no applications for subventions should be entertained which are made by private proprietors for the planting of small widely separated pieces of ground, and which would requirethe Admini- stration to expend money unprofitably, without the possibility of superin- tending and controlling such widely scattered replenishings. ‘“ RemarKs.—Certain rules, most assuredly, ought to be observed in the allocation of subventions. The rebotisement of a territory which is not attached to any similar operation completed or to be under- taken, in most cases, will be of no advantage to the general interest, and will not be of such a nature as to be encouraged by the State. It will therefore be well, in case of requests for subventions, to find out in what way the projected rebotsement is related to the public interest, and to keep this relation in view, when allocations of money, seed, or plants are in question. Of course, at the begin- ning of the enterprise, operations aided by the State will be a good deal apart; it cannot be expected that all the proprietors in a given area will resolve to effect these repeuplements contiguously. But it is necessary to prevent the distances being so great as to make the control of the subventions and the superintendence of the works too difficult. “Tt was proposed that rewards should be given to communes or to private proprietors who shall be the first to enclose their lands, “Romarks,—The law regarding mountain rebotsement limits its opera- tion to works of reboisement strictly so-called. No portion of the funds devoted to this work can be employed as premiums to pro- prietors who may take the initiative in the enclosure of all, or of a part, of their estates. But this can be always done as regards the communes, by appealing to the law concerning bringing in the waste communal lands. RESUME OF CONFERENCES In 1861, 178 “The proposal can be made at the proper time to the Superior Com- mission charged with presiding over the combined operation of the aforesaid law, and the law of rebotsement. “Questions relating to forest improvement have remained till now, and especially in the south, too much confined to a narrow circle. It is very important to make them known in every possible way. A periodical publi- cation has just appeared under the title of Revue agricole et forestiere de la Provence. Everything relating to forests, and especially the question of the reboisement des montagnes, are to be therein treated of, with the necessary developments. An appeal has been made for help from those who wish to popularise forest science. “ RemaRKs.—Government cannot hesitate to encourage the enlighten- ment of the popular mind respecting questions connected with the prosperity of the forests. A subvention of 500 francs has been granted to the Revue agricole et forestiere dela Provence from the funds for ‘mountain reboisement. It is desirable that the employés should lend their help to this work of enlightenment. REBOISEMENTS OBLIGATOIRES, OR ENJOINED REBOISEMENTS, “Important rebovsements have been effected in certain departments, more especially in the Puy-de-Déme, and in the Haute-Loire, with the help of the enactments in the last paragraph of Article 90 of the forest code. Those employed have enquired if they may not continue to proceed in the same way wherever it is possible. Government will thus possess an additional means of carrying on mountain reboisements. “ Remargs.—The law of 28th July 1860 has not abrogated any of the enactments of the forest code, and there is nothing to hinder Article 90 from being applied wherever this means of reboisement can be advantageously employed. ; “The agents employed have usually agreed upon the best way of finding out where compulsory reboisements ought to be effected. For example, suppose a river, resembling a torrent like the Durance, the flow of which it is necessary to restrain: the first thing done is to study the whole basin, beginning at the source of the stream, attentively following its course, ‘either on the spot or on a map furnishing sufficient details of the principal and second tributaries ; and after this preliminary study, operations are projected at different points in the basin in the order of urgency. They have proceeded in this way in the Basses-Alpes, in the Hautes-Alpes, in La Dréme, where all the operations, either projected or in the course of execu- tion, aim at regulating the flow of the Durance and its tributaries, such as the Ubage, the Bléone, the Asse, the Buech; in La Dréme, L’Aigue, L’Ouvers, Le Bez. “RemaRrKs.—If it be necessary to concentrate operations in reborsement where they are only sanctioned, this proceeding is much more important when they are declared to be of public utility. Isolated observations should not be made, but on the contrary all should be connected with a plan of operations converging to the same end. It is very essential to demonstrate by facts the advantage of these operations. It is necessary, where the examination of a given area is determined, that it should be pursued through all parts of the area where the rush of water is to be restrained, so that when the enterprise is completed the demonstration of the effect of the reboise- ment should be perfect and conclusive, ‘ 174 LEGISLATION ON TORRENTS, “ A question has been raised as to the relative importance of reboisement and gazonnement for the consolidation of the soil and the creation of obstacles to the sudden overflow of streams. Several engineers, especially in the Alps, appear disposed to think that gazonnement is often the most suitable means of attaining the proposed end. Other experts are of opinion that if in certain cases gazonnement may appear enough, rebovsement will more slowly but more completely and durably effect a result. “ Remarks.—There seems to be attributed to gazonnement, especially in the Hautes-Alpes, in L’Isére, and in the La Dréme, a power almost as great as that of rebovsement for restraining torrents. This is a little exaggeration. The Administration does not deny the utility of restoring the turf, but works of this kind should be undertaken on the vast bare surfaces which extend above the region of forest vege- tation. Executed simultaneously with repeuplements, they give powerful aid in hindering the rush of torrents into the valleys; in order to seek this result by a double means, the Administration has promoted the formation of a higher commission for the simultaneous execution of the two laws on reboisement and reclaiming of waste communal lands. But everywhere where repeuplement is practicable this latter seems to promise to be the most efficacious means. The employés are mistaken if they think themselves obliged every- where to propose immediate rebovsements with valuable trees. When the soil is nearly exhausted, and requires to be renewed before being fit for the production of forest trees, it should be planted with bushes or hardy shrubs, such as exist here and there on the barest parts of the mountains. This work is included in the category of repeuple- ments, properly so called, and constitutes a real reboisement. The circular No. 806 contains, on this point, pages 7 and 8, all the necessary hints. According to the enactments of this circular, the examination of ground for compulsory reboisement should include grounds to be rebotséd either with permanent trees or with prepara- tory plantations, and grounds on which it is necessary to carry out works of gazonnement. “The replenishings with woods may be effected through the operation of the law for bringing in the waste communal lands, These under- takings should furnish all necessary hints; and those of them which include operations belonging to both categories will be handed over to the high commission appointed by the decree of 7th November 1861. “In La Haute-Leire, the employés entrusted with the survey of districts for compulsory reboisement have declared that they are often at a logs, on account of the peculiarities of the soil, consisting of waste pasture, partly wooded, but forming no greater obstacle to the torrents than if it were entirely bare. They have asked the conferenee to decide whether districts of this kind, which do not cover less than 65,000 hectares in the depart- ment, may be included in the périmétres obligatoires. The employés, assembled in conference at Aurillac, did not hesitate to answer in the affirmative, at the same time referring the question to the Administration. “ RemarKs.—The principal object of the law of 28th July 1860 ig the creation of barriers to the sudden descent of torrents into the valleys. There is no doubt that districts sparsely covered with trees, having no hydraulic effect, should be included in the extent RESUME OF CONFERENCES IN 1861. 175 to be reboiséd when there is an opportunity for fixing or determining a périmétre obligatoire or area of enjoined reboisement. “The form to be given to enterprises of compulsory reboisement has been the subjeet of a detailed examination. It has been acknowledged that up to this time these enterprises differ very slightly, and that experience will supply the most useful indications for the simplification and modification of these projects. “ RemaRKs.—It does not seem that the proper time has come for pre- scribing a determinate form to enterprises of compulsory reboisement. The number of those examined by the Administration, up to this date, is not large enough to enable one to decide on the best form for these undertakings. On the other hand, no great difference has been observed in the plans presented by the officials of the different dis- tricts. The only remark that there is any need to make is that some officials have assigned too long a time—10 or 20 years—for the completion of the work. The Administration has pointed out that such a delay is incompatible with the rapidity which, from every point of view, is seen to be very desirable. It has just repeated that, when reboisement with long-lived trees is not immediately possible, the ground can be stocked with shrubs of an inferior order : an opera- tion which can almost always be effected at once, and which is really included in the category of reboisements, properly so-called. “Tt should be added to the instructions given—(1) That when a pro prietor possesses several pieces of ground in the périmétre, these pieces may be grouped together if they fall under the application of similar measures ; (2) That it is not necessary to point out the sub- vention to be allotted to each piece, but that those pieces may be grouped together for which the same proportionate subvention is proposed, and the importance of each group may be known by the proportional per cent. of the expense ; and (3) That pieces may be grouped together, the value of which has been fixed by their yielding the same amount yearly. ‘ SUBVENTIONS. “ Various observations have been made upon the allocations of Govern- ment subyentions for works of reboisement. One employé has expressed the opinion that it will be difficult, according to circumstances and according to locality, to grant subventions of variable importance, and to absolve in certain cases, the communes from all expense, on account of considering, as a direct participation in the expense of the reborsement, the allocation of a subvention from the treasury of the Department. This employé has, in fine, requested that a maximum should be fixed, for example, say 80 per cent. of the expense for the communes, and 60 per cent. for private individuals, a maximum which must not in any case be exceeded in the offers of subventions from the State or from the Department. “‘ Rumarcs.—The subvention is in its very nature variable. It depends on the importance of the repeuplement, or restocking, with regard to the public interest, the attitude of the public mind in the district with regard to mountain reboisement, the more or less easy position of the proprietors, and on various other analogous circumstances which it does not appear necesssary to detail. From thence it follows that the Administration should specially reserve the power 176 LEGISLATION ON TORRENTS, of taking into consideration on each demand, the amount of the subvention to be granted. A maximum cannot therefore be fixed. As regards the communes, the Administration intends, where required, to consider the subventions voted by the General Councils of the departments as a direct participation in bearing the expense of the works. | “ Several employés have given an opinion that subventions ought to be offered in preference to proprietors whose land is included in the périmétres, 80 as especially to encourage reboisements of acknowledged public utility. “ Remargs.—The law grants subventiuns in cases of sanctioned reboise- ment, and in cases of compulsory reborsement; the Administration will proportion in both these cases the amount of the subventions to the expected result of the enterprise, regard being had principally to the public interest. “ METHOD OF CARRYING ON OPERATIONS. “ Nursertes.—After different opinions had been expressed in regard to the extent which should be given to nurseries, it was agreed that this should depend on the yield of the nursery and the extent of territory to be reboiséd, “There were various opinions expressed upon the point, whether it would be better to form great central nurseries which would cost less and be more easily superintended, or to form a great number of small nurseries scattered over the district to be reboiséd, which would have the advantage of placing plants more within the reach of the districts to be re-wooded. “ RemaRKs.—The chief effect of establishing large central nurseries in close proximity to the great populous centres, is to attract public attention, and by degrees to invite the proprietors of waste mountain land to reboisement, by the facilities which are offered them for pro- curing all that is needful for the operation. Nurseries of this kind can also be better and more cheaply taken care of. Atthe same time nothing is absolutely fixed on this point, and there is no reason to prefer one system to the other. “There were also diverse opinions expressed in regard to how nursery ground should be selected. Some thought that nurseries ought to be formed on the best soil of the district to be reboiséd, so as to produce healthy plants. Others were of opinion that nurseries should be formed where there were average conditions of climate, fertility, and altitude, so as to produce plants which would run no risk of dying from a too rapid change when transplanted. “From the same view, an opinion was expressed that in general it was not good to manure the soil; but that in cases where manure appeared necessary to pulverise the soil or to repair its losses, vegetable compost should be used, and more especially that which was collected in the woods. “ Remarxs.—If the nursery can be placed where the soil is good and at a moderate distance from the districts to be reboiséd, it will evidently be of advantage to the State to become its proprietor. There are nearly always dangers in fixing the position of a nursery, if care be not taken to stipulate in the leases the guarantees necessary to pro- tect the interests of the State. There is reason to believe that in most cases the purchase is of greater importance than the situation since the State can always, when necessary, sell the land which has been improved by culture, when it becomes useless as a nursery, RESUME OF CONFERENCES IN 1861. 177 “Tt is agreed that the ground should be thoroughly pulverised and dug to at least the depth of 30 centimétres, or 12 inches. All were not of one opinion as to the quantity of seed necessary for stocking a nursery. As to pine seeds, such as are principally made use of in mountain reboisement, the calculation towards which most opinions seemed to converge, was from 8 to 10 kilogrammes of seed per are. “ Sowing the entire nursery, and extracting the plants from a third of the extent at the end of two years, with an immediate re-sowing of the ground, and so on for the two other thirds, appeared to some an economical plan, yielding satisfactory results. By this system the plants would be used without being previously planted out. “Others thought that with regard to nurseries there should be less thought of the expense than of the benefit to be expected ; and that it was, above all things, necessary, especially at the beginning of a great enterprise, to employ all possible means to ensure its success ; and that, with this in view, the ground should be divided into strips, which should alternately be sown and left unoccupied; that the young trees should be planted out carefully, to allow of a proper development of the root ; and finally, that the sowings should be graduated in such a way as to obtain a difference of age favourable fur transplantation. “ Remarks.—The idea underlying this suggestion is a sound one. Attention should be given primarily to the efficiency of the nursery, and the question of saving expense be considered secondary to this. “ For stocking the nurseries, it has appeared right to employ, as muchas possible, seed grown in the locality, or in the immediate neighbourhood. It has been thought good to employ shelter of every kind,—branches, stretched out cloth, straw quilted between canvas or cord, fern, and screens of arbor vitae. Some were of opinion that the plants should be watered, but with much caution; and it was thought that, although in certain localities indispensable, there was in most cases the inconvenience of accustoming . the plants toa moisture which would not always be maintained, and of thus making them more sensitive to the action of heat. “Other operations, such as binage and hoeing, were considered by every one to be indispensable. “ All were also unanimously of opinion that the nursery should be enclosed, and that nurseries of any extent should be provided with a hut as a shelter and tool-house. “ RumarKs.—There have been recoramended, as sufficient and econo- mical fences, either simple ditches, wide enough to present obstacles to the incursions of animals, or parallel lines of wire fencing, fixed at regular distances to wooden posts. “ As a, useful precaution in transporting, it was recommended to cover the roots with a mixture of clay and cow-dung. “Opinions were very various as to the season for sowing, mode of culture, and several details as to keeping in proper order. “‘ RemaRKs.—Experience alone can provide useful hints as to what is most suitable to each locality. “ CHorce or TREES. « The employés have not been able as yet to submit well prepared returns as to the kind of trees to be used in mountain reboisement. Up to this date, the trees principally used have been the épicéa, or Norway fir, the U 178 LEGISLATION ON TORRENTS. Scotch fir, the black Austrian pine, the pine of Aleppo, the Corsican pine, and the ailanthus, which have generally succeeded,—the larch, which has failed in certain places because the ground was too damp and the elevation too low,—and the acacia, which has failed when planted at too great an{eleva- tion, but has succeeded lower down. The Atlas cedar has been used in several districts. “ Deciduous trees, such as the white oak, the green oak, the Liege oak, the chestnut, the willow, the white poplar, and the birch, have been success- fully planted in several places ; shrubs, such as ?’'amél, anchier, the sumach, the hazel, &c., have already afforded gqod results in preparing the soil for a stock of valuable trees. “ RemarKs.—lIt is well to attend to the indications supplied by Nature in each locality, especially where there is any question of replanting with shrubs or inferior vegetation. There is nothing to hinder a trial of new essences, or kinds of trees, when this is made with requisite caution. Thus, the ailanthus, recently tried in several places, has everywhere yielded good results. The same can be said of the Austrian pine, which almost universally succeeds in calcareous soil, and at the most varied altitudes. It will be only after a number of experiments that it will be possible to classify with any amount of precision the kinds of trees, by regions and by zones of altitude. “Tn Germany, a mixture of Norway firs and larches is generally considered a good one. “ A mixture of oak and Scotch fir is also recommended at points where the former has a chance of succeeding. “ One cause of the failure in sowing larches is having placed the seed at too great a depth. Larch sced should be covered very lightly with earth. “ Mops oF Execution or Works oF REBOISEMENT. “ After preparing the ground—in doing which, especially on the slopes, great care should be taken not to disturb the soil too much—it is necessary to proceed with the work of repeuplement, or restocking with trees. Opinions are divided as to whether sowing should be preferred to planting, or vice vers. “Many are inclined to think that sowing should be employed, as more economical in temperate districts, where success is sure, but that planting is to be preferred at greater altitudes. “ There is, moreover, a mode of sowing, known as semis @ la niege, which has been several times employed successfully, and which will facilitate the stocking of large surfaces at the smal] outlay of from 25 to 30 francs per hectare. “ Sowings of larch seed on the snow have several times succeeded in the Hautes Alpes, and in the Basses Alpes, and it is proposed to make similar experiments in these districts with other seeds. “ When the ordinary mode of sowing is employed, it is advantageous to sow early, that is to say, at the beginning of spring, so as to avoid the too sudden effects of the summer heat. “ Sowing by means of potets placettes has appeared most suitable for clothing uneven surfaces, or friable soil. The quantity of seed to be used is calculated, on an average, at 3 hectolitres of mast per hectare, at 6 or 8 RESUME OF CONFERENCES IN 1861. 179 kilogrammes of Scotch fir, or of similar seed, and at 6 kilogrammes of larch. This quantity ought to be doubled when the sowing is done in strips. These quantities are, besides, essentially variable, according to circum- stances and locality. . “ Remarks.—The Administration thinks it proper to recommend the sowing of seed upon the snows. Although its success has not yet been tested in a sufficient number of places, there is reason sufficient to employ it with different kinds of seeds, and in different places, where it may be likely to succeed. It is not necessary to enlarge on the advantages of so simple and economical a mode of repeuplement, “Qn volcanic soil, covered with scanty heath, good results have been obtained by sowing broadcast, without any further preparation than a simple ecobwage when the long thistle heath hinders the seed from reaching the ground. “The necessity for early sowing cannot be too much insisted on,—in March, for example, when they can profit by a few fine days, often very soon followed by snow and rain. Germination then takes place under favourable conditions, and the young plant is able to resist the great heat, which would have killed it if the sowing had been deferred until the last snow had melted. “Tt is desirable to form artificial shelter wherever it is possible. When planting is the mode chosen, the season chosen is not the same in every district. Opinions are not agreed on this point. In Provence it has appeared that almost invariably planting in autumn is to be preferred, because of the early season of the droughts, and on account of the scarcity of workmen who are resuming their agricultural employments. “The age at which plants should be used is very variable. In the high regions of the Dréme and the Isére, it has been remarked that plants should be strong in proportion to the elevation of the district. It is good at such points only to plant trees which are four or five years old at the least. “The quantity of plants per hectare is necessarily variable, only strictly local indications can be given on the point. “ The expense of the stocking per hectare has not yet received a sufficiently approximate calculation. Experience alone can furnish the data necessary. “Several employés have considered the question, whether the mode of working by contract might not be advantageous and economical for the pre- paration of the soil ; without being quite decided, they are inclined to think that this mode of proceeding may be useful. “ Remarks.—It does not appear that there are as yet sufficient grounds for throwing open the operations to private speculation. It is onl: after they have been for a long time carried on economically that it will be advisable to substitute contract for Government management. “The scarcity of workmen in certain districts, and especially in the Alps, has engaged the attention of the agents, who have expressed a wish that the Administration would interfere and obtain from the Minister of War the paid assistance of military workmen when circumstances permit. “Remarks.—The Administration will most willingly negotiate this matter with the Minister of War when it becomes necessary. But to do this it must be able to specify and define the proposal, and let him know the situation and extent of the operations, their duration, the time when they will take place, the number of workmen required, 180 LEGISLATION ON TORRENTS. the point from which they should be sent, the pay which they will receive, &c. “Several employés are of opinion that the special staff of the reboisements should be in keeping with the increasing development of the operations, and that the employés composing this staff be entrusted with the execution of the enterprises which they have suggested, with the assistance of the local employés, during the ¢'sposable time left to these latter employés by the requirements of their ordinary duties. “ RemaRks.—The Administration proposes to entrust special agenta with the work of reboisement, not only in what regards the prepara- tion for the undertaking, bu: also the execution. This service will also be placed in due time in a position to grapple with new exigencies as they may present themselves. “At the same time, the Administration does not intend that the employés of the ordinary service shall consider themselves relieved from all participation in the operation in question. “ Negotiations with proprietors of waste mountain land, for the purpose of engaging them in rebotsement,—the giving due notice in regard to the demands for subventions for reboisements facultatifs,—the super- vision of execution of operations of repeuplement,—the giving of assist- ance in operations of enjoined reboisement when they take place,—will be a part of the functions and duties of the officials attached to the ordinary service. The Administration has pleasure in believing that all the officials will assist the enterprise with all necessary zeal and devotion. “Such are the principal questions which have occupied the employés assembled in conference on the 9th, 10th, and 11th December, at Valence, Aurillac, and Tarbes. “ These agents have, moreover, given a concise account of the operations already completed, and of those which are projected. The repetition here of this account would be uninteresting. Concerning the completed works, the Administration will find more circumstantial details in the statements Nos. 16 and 17, which should be produced, in accordance with the circular No. 806. As to the projected operations, special notes will be supplied by the conservators, each regarding what concerns his own circuit. “(Signed )—H. Vicarrn, Director-General of Forest Administration. “Paris, 10th January 1862.” The following is a résumé, or abstract, of the official report of operations carried on in 1861 submitted by the Administration :— “A. Reboisements facultatifs, or sanctioned operations. “Tf the comparative unimportance of the greater part of the works, and if the wide dispersion of these do not permit them to be included to-day in the general system of defence against torrents, they tend at least efficaciously to accomplish the object which the Legislature had in view. “These reboisements, though partial, are in effect creating woods, which, though now isolated, by successively effected combinations will prepare for the future, masses of important forests. On the other hand, the rendering productive lands which have remained until this time unproductive consti- tutes a true agricultural progress. “There have been received, in 1861, 695 demands for subventions, ABSTRACT REPORT 1861. 181 almost all of which have been approved. And the communes have com- peted energetically with private proprietors. “The extent of communal lands rewooded by aid of subventions is 2653 hectares. The regions of the Alps, and the Pyrenees, and the central plateau, have been the sites of the greater part of these reboisements. The lands replanted with woods by private proprietors comprise 584 hectares. “ Besides, there have been executed works of reboisement on 1402 hectares of State lands on the mountains. “In all, 4639 hectares. The expenses have been 372,000 francs, or 80 francs per hectare; the proportion of this paid by the State has been 200,000 francs. “ B. Reboisements obligatoires, or enjoined reboisements. “ Of 1,100,000 hectares of lands capable of being rewooded, the resources put at the disposal of the Forest Administration did not admit of actual reboisement over an area of more than 80,000 hectares. It has been necessary first of all to determine what were the localities where the works were most urgently required, and it is towards the origin or source of the water-courses that the explorations have been directed. “There were taken into consideration 129 projects of redoisement, embracing 107,474 hectares of land situated in the Alps, the Pyrenees, and the mountains of central France. These lands are not all designed to be replanted with trees; a portion will require to be preserved as pasturage, subject to regulation of trespass ; the remaindermay be successively replanted in definite portions annually, either immediately or after the preparation of the soil by the erection of fences, and by the natural or artificial production of vegetation of an inferior order.” A second conference of agents employed was held in 1862, on 8th September, and following days, at Clermont-Ferrand, for the regions of the mountains of Central France; at the same time, at Carpentras, for the region of the Alps ; and on 15th September, and following days, at Foix, for the region of the Pyrenees. Of these conferences, the following is a résumé, with annotations by the Administration :— “J, REBOISEMENTS FacuLTaTirs, SANCTIONED REBOISEMENTS. “ First Questron. “Up to the present time numerous applications for aid in carrying out sanctioned works of reboisement have been made by communes, by public bodies, and by private proprietors. The Administration has reason to believe that the parties for whom this aid is desired, and more especially the private proprietors, do not always possess the information necessary to enable them to make the most of such aid. “The Administration has reason to believe that it can in general rely with confidence only on works of restocking woods effected by itself, or under its direction. Again, looking at the subject from another point of view, the reboisement carried out on scattered patches, and often very imperfectly, will not effect the object in view excepting in so far as they shall by combination form, sooner or later, a sufficient and effective protec- tion to the soil. “In accordance with these views, it is not unreasonable to enquire 182 LEGISLATION ON TORRENTS. whether it would not be desirable to specify zones, beyond which aid shall not be given for vebovsements facultatifs, excepting in special cases of con- siderable extent, presenting an indisputable character of public utility, and holding out in every way a probability of success. Within these zones the work would be carried on under the superintendence of the overseers actually employed in the vicinity, or of special overseers, the number of which it will be necessary to determine. “ Opinions and Propositions of the Agents, “The members of the conference at Clermont were not altogether agreed as to the circumstances in which the specifying of such zones should be carried out. Some were of opinion that the measure, though unneces- sary in regard to communal lands—for the reforesting of which the Admini- stration is furnished with sufficient authority—would produce good effects in its application to private lands. Others have alleged, against the proposed measure, the difficulty of its application. And the conference, without pro- nouncing finally upon the question, has expressed the opinion that the creation of such zones might be considered a very useful measure ; but it was remarked that the measure should not have the effect of binding agents, or fettering their personal action, so as to prevent this aid being given to demands relating to lands situated out of the zones, when the reforesting of these lands should present a marked character of public utility. “ The agents of the conference at Foix expressed the opinion that it is useless, and would be inconvenient, to establish zones for communal reforesting. ‘The members of the conference at Carpentras acknowledged that it is indispensable, in order to the good use of subventions, that sanctioned works of reforesting should be carried out by the Administration, and that consequently it would be desirable to fix the zones. They think, however, that the grounds are not yet sufficiently explored, nor the spirit of the population sufficiently known, for this demarcation to be possible at present. The agents were desirous also that, except in exceptional cases in sanctioned works of reforesting, a minimum extent—say, for example, of 10 hectares— should be specified for every one operation, whether on land belonging to one proprietor or to more. “ Remarks and Instructions of the Administration. “The Administration does not think proper to insist on the reboisements facultatifs. “The work of reboisement on the mountains is so recent that it is deemed desirable still to allow every latitude in framing the demands for aid. “Every demand brought forward will, as heretofore, be the object of a special examination, without there being fixed a minimum of operations. “Only, the demands being for the most part called forth by the direct intervention of the agents with the proprietors, the measures ought to be directed as much as possible in such a way that the works effected, or to be effected in the same region, should concur to a common object. With these views it would not be possible to estimate at present the number of persons whom it would be necessary to appoint over the works. The creation of new employments of the guard for reforesting will go on. The creation of new employ- ments for those engaged as puards in connection with rebodsenent RESUME OF CONFERENCES In 1862. 183 will go on as heretofore, and, until fresh orders, according to the present scale and the requirements of the service. “ Second Question. “Hitherto the applications for aid have been transmittéd to the Adminis- tration as fast as their submission by the proprietors of the reforested lands. The number of these applications having now become considerable, it appears necessary now to group them so as to send up several at one time. “Tt is desirable to ascertain at what time the transmission of these should take place, so as to secure at the proper season the execution of the works. “ Opinions and Proposals of the Agents. “The agents at the conference at Clermont advised that the applications for aid in reforesting by communities should be produced before the 15th July for the autumnal labours of the same year and the succeeding spring, and that these demands should reach the Administration by September Ist. “ At the conference at Foix the agents deemed that the demands relating to the works in spring might be drawn up before October Ist, and sent at that date to the Administration, and that for the reforesting in autumn they should be sent in by May Ist. “The conference was of opinion that no date should be fixed for sending the requests to the agent, but that the latter should be authorised to put ‘off till the following year the preparation of every demand which might not reach him two months before the general despatch relating to the season for executing the works. . “ According to the opinion of the conference at Carpentras, it is better to fix two dates for sending off the reports—z.e. 1st October, for the works to be carried on in the spring of the following year, and June 1st for those of the autumn of the same year. “ Remarks and Instructions of the Administration. “Tt seems to be well to fix upon two periods for forwarding collected applications for aid on sanctioned reboisements to the Administration, accompanied by a report on the same—that is to say, June lst for- the autumn works ; October 1st for the works of the ensuing spring. Any demand which shall not reach the superintendent of the depart- ment a month before each of these fixed times may be carried over by the chief of the department to the following season, or following year ; and this chief will be the judge in the case in which a demand for aid should be separately sent in to the Administration out of the prescribed periods. “Third Question. “The Administration has caused to be prepared a form of report for instruction on applications for aid. It is desirable to ascertain whether this formula embraces all the points on which information is required. “ Opinions, éc., of the Agents. “The three conferences have proposed to adopt the formula proposed by the Administration, with some slight modifications. “ Remarks and Instructions of the Administration. “The model of the report has been sent to the conservators by the Administration in sufficient number of copies for the requirements of the service. “When an agent shall have to send at one time a number of applica- 184 LEGISLATION ON TORRENTS. tions, it will be unnecessary to add to each a special report. The attestation of the requests oan be verified by a collective statement in writing, conformably to the directions of the formula. “TI. REBOISEMENTS OBLIGATOIRES, OR ENJOINED REBOISEMENTS. “ Fourth question. “Tn the plans for enjoined reforesting, the estimate of the expense of the works, as well as the division of this expense among the parties interested, the fixing of the subsidy, and the estimation of the revenue and of the value of the lots, can be given approximately. If further simplifications should be desirable, the agents are desired to prepare a statement of these, after having discussed the subject in conference. “ Opinions, &e., of the Agents. “ The conference at Clermont remarks that, in a certain number of projects already presented, it has been thought best to unite in one group the different lots belonging to the same proprietor. This measure, which is tedious and laborious, does not appear to the agents to be of much use. “The same conference remarks that the Administration has returned several plans of enjoined reforesting, on account of stipulutions for too long a delay in the execution of the works. The agents think that a con- siderable latitude should be left in this respect, as well as for the other details of execution. “ Remarks, &e., of the Administration. “The union of different lots belonging to the same proprietor, useful in certain cases, is not prescribed absolutely. The Administration leaves to the agents to decide whether or not there be reason for doing so. “The Administration considers that it is desirable to push on energet- ically the execution of the works, and that, in this point of view, it is inconvenient to stipulate in the plans for the long delays which interested parties may desire the Administration to sanction. “Tt is certainly necessary to allow all possible discretion in execution ; but it is necessary also to avoid raising hindrances of a kind to paralyse the effort of the Administration, and to hinder it in giving, or trying to give, a fresh impulse to the progress of the works, as circumstances may require. “The agents submit to the Administration the question—Whether the directions, relative to the designation of two proprietors as members of the special commission, instituted by the fifth Article of the law of the 28th July 1860, should be understood of two proprietors of each commune comprised within the area of reboisement, or only of two proprietors for all the communes? The agents of the conference at Foix have not pointed out any further simplification required. “The composition of the commission lies with the prefect ; it belongs, then, to this magistrate to interpret, according to his judgment, the directions of the law in this respect. “The Administration deems that in appointing two proprietors to take part in the commission, the Legislature had in view to introduce into this commission members possessing knowledge of localities and their requirements, and not of persons directly interested in the operation only. : RESUME OF CONFERENCES IN 1862. 185 “With this view two proprietors would suffice not only for one périmétre, or area of reboisement, but also for several périmétres in the same district. “In the conference at Carpentras, the agents have expressed the opinion that it is better to leave as much latitude as possible to the verbal report, and to the written account of the examination of the land, and that the specifications of the works proposed for execution should be on printed forms, supplied by the Administration, : “ Remarks, &c., of the Administration. “The form of the specification of works proposed for execution being susceptible of variation according to circumstances, it does not appear desirable to provide a separate form for this any more than for the report of survey and descriptive memoir. “Some agents have expressed an opinion that it would help the full understanding of the report if there were indicated on the charts the lay, or inclination of the land, the general water-shed, and the flow of the waters. “ Remarks, &c., of the Administration, “These suggestions are valuable, and the Administration strongly recommends to the agents to carry them out in the preparation of plans for projected works. “< Fifth Question. “Tt should be ascertained whether it would not be well to prepare for every périmétre, or specified area of reboisement, a detached statement, in which shall be anticipated all the cases mentioned in chaps. i. and ii. (secs. 1 and 2) of part iii. of the decree, regulating the reforesting, of April 27 1861. In this statement should be classed in order all the lots included in the périmétre, with indications of the course followed with each of them, and of the expense of the same. In it especially should be included all the necessary elements for establishing the annual accounts mentioned in Arts. 26, 27, and 28 of the above-mentioned decree. “ Opinions, de., of the Agents. “The agents of the conference at Clermont expressed the opinion that it is impossible, in the case of a périmétre composed of a great number of separate lots of small extent, to keep a separate account for each lot of the quantity of seed and of the manual labour employed ; that it is only necessary to keep one account of the whole of the lots requiring the same expenditure in execution of the work reforested the same year ; and that it would be easy to estimate from this account, at the end of the year, the cost per hectare of each parcel, as well as the expense to each proprietor. “ Some agents proposed the keeping of two statements for each périmétre-— the one to contain statements of all the lots included in the périmétre, and in which account would be kept of the changes effected on each lot by each proprietor ; the other, which should be destined for the total of the lots reforested the same year, supplying all the information relative to this reforesting. “The conference expressed definitively the opinion, that on account of the variety of conditicns occurring in different districts, the Administration cannot well prescribe the use of the same form of account in all; and that at present uniformity should only be required in half-yearly estimates, to be transmitted to the Administration in accordance with the circular No, 806. x 186 LEGISLATION ON TORRENTS. “The agents of the conference at Foix proposed the formation of a state- ment comprising seven principal divisions, each corresponding to ‘one of the seven cases provided for in chapters I. and II. of title III. of the decree of 1861’; each one of these principal divisions to be divided into columns, corresponding yearly to the different details of the work. “The conference at Carpentras submitted a form of statement which it considered would meet the case. “ Remarks, &c., of the Administration. “The different forms of statements presented by the conferences have not appeared sufficiently definite to produce a form adequately simple and clear to meet all the instructions proposed. This is naturally explained by the fact that, as the works of obligatory reforesting have scarcely begun to be executed, the progress of these works has not yet presented the opportunity of these being studied. In these ‘circumstances, the Administration does not feel called on to prescribe a uniform rule, which probably would require to undergo numerous modifications in the course of its workiug. “The Administration thinks it proper to pospone the settlement of this question till it shall be more-enlightened in regard to details to which the question relates. At present it confines itself to recom- mending to the agents to supply all the information likely to be useful, whether this be done in the form of a statement, the substance of which is optional, or under the form of instructions, prepared with care and method, in the file of papers supplied for each périmétre. ‘As to what relates to the determining of expenses, as it would be impossible, as the agents of the conference of Aurillac have deemed it to be, to keep an account in detail of the expenses belonging to each lot, the expenses will be calculated annually, when there is occasion so to do, from the account of the expense established by hectare for the whole of the lands comprised in the périmétre, “ Sixth Question. “Tt will be desirable to consider, if it would not be well to establish, for each périmétre, a statement in which the periodical phases of the operation of reforesting shall be recorded. “ Opinions, &e., of the Agents. “The agents presented different forms of statements intended to meet the requirements of the question. © “ Remarks, d&e., of the Administration. “The same remarks and instructions as have been given in relation to the preceding question, are applicable. “TIT, Exzourion oF tan Works. « Seventh Question. “In what cases is it proper to proceed to the restocking of woods by planting? and in what by sowing? “ Opinions of Agents. “‘ According to the agents at the conference at Clermont, the sowing, being more economical than plantations, making more certain the retaining of the land and opposing greater obstacles to the flow of waters, ought to be preferred to plantations in view of the object of the law of 1860 ; but when the works RESUME OF CONFERENOES IN 1862, 187 are at great altitudes on steep declivities, not well adapted for retaining the seed, and in certain soils, such as the chalks of La Bresse, or the calcarious schists of La Lozére, it will be necessary to have recourse to plantation... “ At Foix, the agents express the opinion, that, it. is better to. proceed exclusively by means of plantation in the elevated parts, and only to employ sowing in connection with planting in the places of medium sie oi and low parts, where frosts are less to be feared. “ At Carpentras, the agents were of opinion that plantation j is preferable to sowing, looking, and looking only, to culture; but that sowing, being more economical, it is better to employ it when it appears to offer sufficient chances of success. “ Remarks, dc., of the Administration. “ Without its being possible to point out exactly the cases in which the one or the other of the two modes of procedure should be followed, it seems expedient to admit, as a rule, that plantations, being aubject to fewer destructive agencies than seed-beds, it is better to plant under rigorous and peculiar conditions of climate, locality, or soil. The essential point is to ensure the success of the reforesting of the locality. The question of economy ought undoubtedly to be one of great consideration, but whenever success appears to he certain by one mode and to be doubtful by another, there should be no Meaitte tion in employing the former. “ Bighth Question. “Discuss the kinds of trees selected ; the mode of plantation, singly, or in clumps, &c. ; the number of plants. per hectare; the season best for the execution of the work ; the expense, per hectare, of restocking woods. “ Opinions, &c., of the Agents. “The agents attending the conference at Clermont have experimented successfully with the larch, in reforesting bare lands. “The Norway pine and the pine of the country have given rests which are pretty satisfactory, and they appear to be such trees as should be employed in regions of medium altitude. “The oak, planted but only-to a limited extent in the Puy-de-déme and in the Haute-Loire, has succeeded well. “The ash, whether planted in large clumps, or intermixed with resinous trees, promises to succeed well in the Haute-Loire. ; “ Remarks, &c., of the Administration. “The indications reported by the agents are based. on experiments actually made, and the Administration has nothing to. add to the contrary. It can only recommend to the ‘agents carefully to note all the facts observed in the different regions, with a view to obtain- ing, when requisite, instruction from these. It is by continual experimenting that the Administration will gradually come to give the operation a more and more satisfactory direction. Hitherto planting single trees has alone been attempted, and this has succeeded very well. It is only from next year that the nurseries of Arpajon, of the Puy, and of the Mende, will present sufficient. resources to permit of the experiment of planting thickets being made. In any case this latter mode could not be at great altitudes, plants of three, four, and five years growth alone succeeding under such ‘conditions. “The number of plants ranges from 7,000 to 11,000, according to the 188 LEGISLATION ON TORRENTS. conditions of soil, exposure, inclination, &c. The most favourable season is spring, in climates where the winters are very severe. In the middle, or low lying districts, autumn seems preferable, on account of its permitting the young plant time to get strength to resist the great heats of summer. The spring seems to suit better for the plantations of resinous trees. There is reason to believe that plantations of these, when the sap begins to move, succeed more certainly. Broad-leaved plants seem to accommodate them- selves better to the autumn planting. “The expense of carrying on the work of plantation amounts, for the hand labour, to 70 francs, by the hectare, in the Loire, to 57 francs in the Haute-Loire, to 48 francs in the Cantal, to 38 francs in Puy-de-Déme. “ Seedlings brought from the depths of forests, and planted in various localities experimentally, with a view to determining the economical importance of such a procedure, have not given satisfactory results. “ Remarks, &c., of the Administration. “ The Administration is aware that plants from the source mentioned have no great value. But in order to avoid the expense of purchase, it was necessary to try to derive some advantages from the resources offered by the forests, until such time as the nurseries shall yield plants. “The conference at Foix was of opinion that it is best to employ the indigenous products of the Pyrenees—such as the Mugho, or dwarf pine, the Scotch fir, the birch, the silver fir, the ash, the beech, the oak, the evergreen oak, the great maple, and the chesnut; and to continue the experiments which had been made with plantations of the Norway pine, the Austrian pine, the acacia, the silver fir, the ailanthus, the larch, the pine of Aleppo, and the mountain pine. These kinds to be distributed according to the altitude, to the local conditions, and to the results of experience. “The planting in separate holes plants transplanted from nurseries seems to offer the best chances of success. The planting in clumps is, however, preferable, when disposing of very young plants taken from a plantation near the lands to be reforested. “The number of plants on each hectare may vary from 10,000 to 2,500, this last number being applicable more especially to saplings, and to the chesnuts, if it be desired to obtain from them poles of good growth at an early age. The season of spring being almost unknown on the mountains, where great heat succeeds, almost always without interval, to the cold of winter, the autumn is in all cases the most convenient season for planting. The price of hand-labour varies from 50 to 100 francs per hectare. The purchase of plants has occasioned an expense of not less than 10, 15, and 25 francs per thousand plants. * Remarks, dc., of the Administration. “The minimum of 2,500 plants per heotare appears very small. The reforesting of the mountains having especially for its object to cover the soil, independently of the addition of future produce, it is better to avoid planting the trees separately, at great distances apart. “The nurseries belonging to the Administration promise soon to supply plants at less expense than that at which at present they can be obtained “The agents at the conference at Carpentras stated that they had employed, on L’Isére, and the High and the Low Alps, the white oak up to 1000 métres of altitude, the acacia up to 900 matres, in all exposures. The RESUME OF CONFERENCES IN 1862, 189 ailanthus had as yet given too little experience for deducing from its use any certain remarks. The Scotch fir, the Norway fir, the Mugho, and the larch, have been employed with success in different situations. In the departments of Vancluse, of the Gard, of the Bouches-du-Rhone, of the Var, of the Maritime Alps, and of L’Herault, there was reason to think that the trees which should be used principally were the white oak, the green oak, the acacia, the maritime pine, the Norway fir, and the larch—at all altitudes, and in situations pointed out by experience. .The planting in holes, taking the precaution to disturb the soil very little, and to procure for the young trees natural shelter—such as bushes, rocks, and the stones which are found on the land—seemed to be the most suitable system of planting. “The mode of planting in clumps, which is very costly, should only be used for resinous trees, and in situations where to secure success is difficult. But this proceeding will always be most advantageous when it is not necessary to regard the question of economy. The best plants are generally transplanted plants of two or three years, “ Remarks, d&c., of the Administration. “The last mentioned method has been made the subject of experi- ment with success. It is not well to attach too much importance to the expense which it occasions: in the first place, the plants being very small, their price is not great ; in the second place, the prepara- tion of the soil is very easy ; finally, as this process is almost always successful, it must be employed without fear in difficult situations, apart in some measure from the question of expense, — “The number of plants per hectare to be employed varies from 10,000 to 16,000 for separate plants, according to the conditions of exposure and soil, , and the kind of tree, etc. For planting in clumps, the number would be - from 30,000 at the rate of 3 plants per hole, and 10,000 holes per hectare. © The planting i in autumn is generally preferable, as giving time for the plants to be in a state to resist the spring frosts and the early heats. “The cost of manual labour varies from 40 to 100 francs. The cost of plants varies too much to allow of an estimate approximately correct being made. “ Ninth Question. “ Sowing.—Discuss the choice of kinds of trees, hi fitness of each mode of sowing, (sowing in rows, in holes, in the open bed, etc.,) the quantity of seed to be used per hectare, the fit season for carrying on the works, the expense of the work per hectare, etc. “ Opinions, d&c., of the Agents. “The agents of the conference at Clermont reckoned that in the central region, wherever the climate is mild, and the altitude a medium one, (800 métres and under,) the oak and chesnut should be employed in preference to every other tree, and if the soil is of poor quality, the resinous trees, the acacia, and ailanthus. “Tn the regions where the climate is more severe, and the altitude greater, | recourse should be had to the Scotch fir, the Austrian pine, the Corsican | pine, the mountain pine, the Norway fir, and the larch. The Atlas cedar, | the larch, and the Siberian cedar can be used for the greatest heights, “No tree, except perhaps the fir-tree and the beech, ought to be rejected in so far as the sowings are made in loco. ” “The least costly and most simple method of sowing, practised for a long 190 LEGISLATION ON TORRENTS. time in the Puy-de-Déme, is sowing at hap-hazard on short heath, or after écobuage if the heath be too high. But this system is not practicable every- where. The method of sowing most usually employed is sowing in rows, or in holes, according to circumstances. In both cases much disturb- ance of the soil is to be avoided. “The quantities of seeds necessary are, for the oak and chesnut, 6 to 10 double décalitres ; for resineous seeds of small size, 10 to 12 kilogrammes, on ordinary land, and a third more if. the conditions be unfavourable ; for the Austrian pine, 12 to 15 kilogrammes ; for the maritime pine, 20 to 25, “The most favourable time for sowing is the autumn for broad-leaved trees, and spring for the resinous. “The spring sowing should be as early as possible in February or March. The cost of hand-labour is, for sowing in bandes, from 30 to 35 francs, per hectare ; and for sowing in potets, from 25 to 30. Reforesting in resinous seeds costs on an average, in central regions, 70 or 80 frances per hectare.. At Foix, the members of the conference were of opinion, that the choice of trees depending essentially on the nature of the land, and on its exposure and altitude, nothing decisive can be pronounced on this head. At the same time it may be concluded, that in elevated regions there will be used with success, the Norway fir, the larch, and the black Austrian pine; in the regions of medium altitude. the pine, the Norway fir, the beech, and the pine intermixed with the beech ; in lower regions, broad-leaved trees in general, the chesnut, the green oak, the ash, and the ailanthus. q “The method of sowing in potets seems to be the most advantageous. The quantity of seed to be used is from 10 to 15 kilogrammes per hectare. “Spring in general is the best season for sowing, especially for resinous seeds. The expense of sowing can be approximately, and in a general way, reported at 100 francs per hectare—z. ¢., 60 francs for manual labour, 36 for the purchase of the seeds, 4 for unforscen expenses. “ At the conference at Carpentras, the agents estimated, that for sowings the trees to be preferred are generally the same as those pointed out for planting, with the addition of the Corsican pine, the cedar, the pine of Aleppo, and the shrubs intended for the preparation of certain soils, or for the prevention of erosion of hill sides, such .as the box-tree, l’argousster Vamélanchier, the barberry, the juniper tree, etc. In L’Ardéche, the sowings of the Norway fir do not offer sufficient chances of success. “Sowing by bandes is preferable whenever it can be employed, but it has the inconvenient disadvantage of loosening the soil too much on the inclines. The method of sowing in potets will be more generally employed. Com- plete or full sowing is the only method possible on rocks, on ground difficult of access, stony parts, and volcanic scorie. The quantity of seed to be employed per hectare is from 7 to 10 kilogrammes for resinous trees, and 3 to 6 hectolitres for the oak. Opinion was much divided on the choice of season. The result appeared, however, to be generally that for resinous trees, and in friable earth, spring ought to be preferred ; whilst autumn appears to suit better for the oak. “The expense of manual labour may be estimated at 60 francs per hectare for sowings par bandes, at 35 francs for sowings par potets. “The price of seeds being approximately, on an average, 3 francs per kilogrammes, the expense will be from 70 to 100 francs per hectare. “ Remarks, dc., of the Administration. “The quantities of seed mentioned by the agents at the conference RESUME OF CONFERENCES In 1862. 191 at Clermont will require to be increased, in so far as larch is con- cerned, the seed of which in general only succeeds in the proportion of 40 to 50. “ Sowing in potets, or drills, seems generally recognised to be the most advantageous. “There is a mode of sowing called semi a la niege, which consists in sowing seeds broadcast on the snow, which melting away deposits these on the soil, anc causes them in some measure to sink partially into the ground. “ Opumions, ke., of the Agents. “No trial of sowing a la mege, as it is called, has yet been made in the central region ; and all experiments in the Pyrenees have failed. In the Alps it was that this mode of sowing was first intoduced, some fifteen or eighteen years ago. The experiment was made in the department of the Basses-Alpes, on a calcareous soil, for a long time unused and covered with grass, and with a northerly exposure ; it succeeded perfectly. The experi- ment was renewed in 1862, in the same department, on 200 hectares, and in the Hautes-Alpes on 40 hectares, with fir, larch, cedar, Norway fir, and Scotch fir. The fir did not succeed ; the larch succeeded only in part on grass lands, and with a northerly exposure ; the cedar succeeded well; as to the Norway fir and Scotch fir the result has not been established. “There were used from 6 to 8 kilogrammes of seeds per hectare; the manual labour cost only 2 francs. “ An attempt made in the Dréme, at 700 métres of altitude, on limy soil, and in a northeast exposure, with the maritime pine, succeeded to a medium extent. “The sowing should be made on soft snow, and in a settled temperature, in order to avoid the floodings caused by the southerly winds and warm rains. “ Remarks, dc., by the Adminstration. “he so-called seme a la niege is very economical, and for this reason one might be tempted to employ this method for the reforesting of largé surfaces. But experience in this matter gives reason to conclude that the results, always uncertain, are generally unsatisfactory. It does not appear that there is any reason for classing this kind of sowing in the category of regular modes of reforesting. But it may be considered as an expedient capable of being employed with success in certain cases. The attempts made up to this time are, however, too few for a certain deduction to be drawn on this point. It might be usful to try further experiments when the conditions shall appear more favourable. Manual labour being at a very low price, there would be no difficulty in increasing the quantity of seed sown, which appears to have been too small in the attempts made in the Basses-Alpes. “TY. Preparatory WoRKS IN REFORESTING. “ Tenth Question. “ Nurseries.—A moderate number of nurseries, of which some are of great importance, have been created by the forest agents, with all the care and intelligence necessary. “Tt is desirable to discuss the processes of extracting and packing the plants, as well as the precautions to be taken at their despatch and receipt, in order to insure their growth ; to study the method of sowing adopted in 192 LEGISLATION ON TORRENTS. the nurseries (in bandes or in potets)—the quantity of seed used per hectare,—the means used for protection,—the expenses of the works. The system of repeated transplanting may be discussed. As soon as the beds produce plants fit to be used, it will be important to have kept, by the official specially charged with the nursery, a register, in which shall be inscribed the number of disposable plants, and the numbers taken away and sent off ; and the conference is to consider the plan that should be adopted in keeping this register, of which an extract shall be periodically addressed to the Administration, that it may know the number of plants ready for use. “ Opinions, &e., of the Agents, “At the conference at Clermont very circumstantial details were pre- sented—taking, for example, the nursery of Arpajon, the creation of which has been attended to with great care, and the state of which is very satis- factory. It may not be uninteresting to reproduce details which answer to the questions put by the Administration, which may serve as useful indications of what may advantageously be done. “Before being sown the bed should be prepared. The preparation con- sists, after having cleared and cleaned the ground, in mixing the natural earth with heath mould for leaf trees, and in adding to the soil some kind of manure. The ground is then carefully broken up. “ Remarks, &c., of the Administration. “Tf the ground be encumbered with weeds it may be well to raise on it a crop of potatoes to secure the destruction of the weeds before appropriating it to the growth of forest seeds. And too much . digging, or displacement of the soil, should be avoided. % “The ground may then be divided into beds, a métre, or 40 inches, in breadth, raised above the level of the ground, and separated by footpaths ; and the beds about 8 or 10 métres long must then be surrounded by sheltering screens or fences of the Chinese arbor vite. While these shelters are growing to a convenient height, their place is supplied by artificial shelters, either formed of straw, or of osier, or hazel lattice work placed nearly vertically, or linen stretched over boards. The sowing is done in the first 15 days of April, or later, if possible, in moist weather. It does not seem necessary to cover the seeds with earth, it is enough to pass the roller over the bed after scattering the seed, and it is covered with moss reduced to small pieces and watered. The quantity of seed to be used per are is 12 kilogrammes for pines with small seeds; 15 to 18 for larch trees, the Norway fir, the black pine of Austria ; 26 to 30 for the fir; for the oak 1 hectolitre ; for the chesnut 6 double decalitres. |The seeds gathered in the country have given much better results than those obtained from purchased seeds. The beds must usually be watered every day until the plants have gained some strength. After the first year the plants can be used. They are then, according to the expression used by the nursery-men, in the con- dition of pourettes. They cost little, 1 to 2 francs the thousand, are easily dug up, and are removed at little expense. But the chances of such young plants taking root being necessarily limited, it is only prudent to use them in moderate conditions of soil and altitude. “ Remarks, é&e. “The lifting of pourettes in the way described is employed with advantage in planting in tufts. The earth raised is divided into clods containing each a certain number of plants, and these plants are conveyed in the clod to the place in which they are to be planted ; RESUME OF CONFERENCES IN 1862, 193 fragments, containing two, three, or four plants, to be put into the. place together, are broken off, and at least one of these almost always grows. : “To obtain hardier plants more likely to take root under severer condi- tions, it is necessary to wait nearly three years, and to have them. trans- planted. The design of this operation is to place the young plants in circumstances favourable for the development of the fibrous root. It is employed for plants of a year old, and should be done in spring, in order not to expose the young subjects to the risk of being raised above the ground by the effects of frost. “Tt has been attempted to avoid the expense of this difficult and costly operation. As regards the oak, one agent has mentioned a process which it may not be uninteresting to bring under the notice of the agents. This process consists in artificially causing the acorns to germinate during the winter, to cut off the radicle and to sow in the seed-beed the acorn thus mutilated. It has been remarked, that the extinguishing of the radicle led to the formation of lateral roots, and to suppress the growth of the descend- ing taproot. “ Remarks, de. “Transplanting does not appear to be always necessary. In the nurseries it is practised at different periods of the plants growth. If, when the plants are required, the best and most fibrous-rooted alone are made choice of, the removal of these will have the effect of relieving the others, and so favouring their development ; in this way plants of different stages of development may be successively removed, and this kind of periodical thinning has for its result, to permit the plants of inferior growth to acquire sufficient strength. This removal is facilitated by the arrangement of the plants being sown in furrows on the flat beds. When it is necessary to thin the plants, there is dug along the furrow a hollow into which the plants are turned ; the proper choice is then very easily made, and the plants remaining in the furrow are easily re-arranged. Finally, the operation of transplanting can sometimes be replaced by the cutting off of the root in the ground, by the use of the spade used at Hagenau (coupe-pivot), which ends in a diamond- shaped edge. ; “The cutting of the root has for its effect to favour the development of a fibrous root This economical and beneficial operation, however, can only be practised in the earths into which the edge of the spade easily penetrates. It has not been attempted in the case of resinous trees ; it would not be without interest to make some attempts in this direction. “The sowings in the nurseries are exposed to ravages by rats, field mice, mole crickets, moles, birds, &c. It does not appear to be necessary to enter into the details of the methods employed to combat these various enemies. The methods followed, moreover, have succeeded only imperfectly,.and it will be necessary to devise others more efficacious. To prepare the plants for sending away, a dry day must be chosen, the digging must be done with the spade, 100 plants are united in one clod, the roots of which are immersed in a bath of well-tempered clayey earth, and they are covered with dry moss; they are then placed in layers in a box with open bars, the spars of which are covered with dry straw. A rapid conveyance is chosen, Y 194 LEGISLATION ON TORRENTS. in order not to leave the plants for more than five or at most seven days in the boxes. On arrival, the plants are immediately unbound and sorted. “ Remarks, &e. “Tt is by the spongeoles or extremities of the fibres that the roots draw from the earth the nourishment of the plant. It is therefore in the highest degree necessary to protect these delicate organs. For this purpose the bath of tempered clay is a very useful precaution. Before putting the plants into the earth, it will be well to leave the roots nearly 24 hours in urine. “This operation has the effect of singularly reviving the vegetative power of the plant. “‘To show the importance of the services that the nurseries are expected to render, the conference at Clermont cited the results of the nursery of Arpajon, formed scarcely two years before. It appeared from the accounts, kept with care in this nursery, that it would contain 32,489,000 plants of various kinds, of the value at a commercial valuation of 159,622 francs. “The details given render necessary a similar circumstantial account of the observations made by the agents at the conferences at Foix and Carpen- tras on the subject of nurseries. “The principal points of the discussion, with those which have called forth differing opinions, will alone be requisite. “ At Foix, the agents considered that the operation of transplanting is too expensive, and requires too great an extent of land, to be followed. A method of taking up plants analogous to that which has been above des- cribed, in the opinions and instructions of the Administrations, seems to be almost sufficient to take the place of transplanting. “Watering appears necessary to be practised with moderation, on account of the expense which it causes. At Foix and at Carpentras, the observations relative to the digging up and packing of plants, as well as the precautions to be taken at their despatch and receipt, do not differ from those presented at the conference at Clermont, and reproduced above. At Carpentras the sowing in furrows has seemed, in all points of view, that deserving to be preferred for nurseries. The quantity of seed necessary to be used has been estimated at 10 or 15 kilogrammes per are for the resinous plants, at 1 or 2 hectolitres for the oak, and at 10 or 15 kilogrammes for the acacia and ailanthus. : “The agents have unanimously expressed the opinion thas it is advisable to diminish the sheltering fences as soon as the plants acquire strength, and that it is necessary to make them always sufficiently low to enable the light to reach easily the plants. The transplanting, which appears to the agents at the conference at Carpentras indispensable for the oak, is considered less necessary for pines and the Norway fir. “Watering, if not indispensable, is at least useful to the resinous trees, and it must, when once commenced, be assiduously pursued. “The agents of the three conferences have presented plans of a register for the record of the plants ready for sending out, and those sent out. “ Remarks, &e. “The form to be adopted temporarily for this register is the following, which must be tried upon formulas prepared in writing in each conservatory till the time when a definitive model, made from ex- periments, shall be adopted -— RESUME OF CONFERENCES IN 1862. 195 NURSERY OF —, PLANTS FIT TO BE DISPOSED OF, . Black Pine of : ‘ Scotch Fir. ‘Anetra. Norway Fir. Observations. . mn mR 5 wa mn . wa nm 5 wm a #6618 88/8 23/8 8 8 mB mh Pm ob BS > mB Bl eR wR B® re aN oO Sa N inn} ri N Er) = NX for) PLANTS SENT OFF, 2 - Black Pine of : F Scotch Fir. Aasieie. Norway Fir. Observations. ° m2 m ° m mn . m Rm . Dm 28 /¢ 59/22 8)8 6 § p> mb B > BB BB Rl] RR OB 5 on nN CO a fo ion) ce NN inn} Sal AN oD The date of des- patch and destina- tion are marked in this column. “This register will be kept by the official in charge of the nursery under the inspection of the chief of the district, “ At the end of every month the work will be repeated by making an entry in each column of the plants then fit to be disposed of, and of those despatched. “ An extract of this register is to be sent to the Administration at the periods to be hereafter specified. * 196 LEGISLATION ON TORRENTS. “ Eleventh Question. : “ Sécherics.—The Administration having ascertained that seeds prepared in the Government drying booths are superior in quality to seeds obtained by purchase, it is desirable to consider whether it be not desirable to erect additional drying-booths (sécheries), or seed depdts. “ Opinions, ke., of the Agents. “The agents at the conference at Clermont have observed that the seeds furnished by the Goverment sécheries, or drying-booths, of Murat (Cantal), or gathered in the country, are incomparably superior to the seed purchased. This sécheric furnishes only 4000 kilogrammes of seeds yearly, which is a quantity much below the requirements of the departments of La Lozére, of Puy-de-Déme, of Cantal, of the Haute-Loire, and of the Loire ; the quantity required annually being estimated at 10,000 kilogrammes, it is desirable to establish a new sécheric. This the conference proposes should be located at Puy. Subsequently another might be constructed at Marvejols. “A member of the conference at Clermont showed that the Corsican pine might be advantageously employed in reboisement,—that the price of the seed of this species is from 7 to 12 francs per kilogramme,—and that, without doubt, it would be possible to establish in Corsica one or two séoheries, by which the seed of the Corsican pine would be furnished at the cost of 4 francs at most. “ The agents at the conference at Foix state that the sécherie of La Lagonne is capable of furnishing annually 4000 kilogrammes of seeds. They think that it would be desirable to establish in the inspection district of Simoux, within reach of the nurseries, a sécherie for fir-tree seeds. “ At Carpentras the agents expressed in general terms the opinion that there would be great advantage in erecting sécherves, or seed depéts, where- ever the existence of extensive masses of forest admit of this being done. “ Remark of the Administration. “Notes have been taken of the different opinions expressed by the agents on the question of establishing new Government sécheries. “ Twelfth Question. “ Examine, and say whether it would not be desirable to gather seeds in the Government forests under the charge of the local officials, and to have them put into places of deposit, from which at a fit time they might be sent off to the places to be reforested. “This measure promises to the agents of the three conferences to be productive of advantageous results. The agents of the conference at Car- pentras express the wish that the gathering should also be made in the communal forests. ‘V, MEASURES FOR SECURING ORDER. “Thirteenth Question. “ Discuss the measures taken to insure the thorough execution of the works, and to justify the use made of the credit accounts opened by the Gavernment. Opinions, dc., of the Agents. “ At Clermont, the conference expressed the opinion that the first condi- tion of the success of the works of veboisement is, that the direction and over- sight of these works should be entrusted exclusively to the agents, and that RESUME OF CONFERENCES IN 1862. 497 it is necessary that a guard should be constantly stationed at the wood-yard of the works. This obligation necessarily causing heavy expenses to the officials, it is desirable to extend the arrangements of circular No. 708 to each official compelled to sleep away from home. “ Remarks, &c., of ,the Administration. : “The Administration is of opinion that the works being executed under the direction of agents gives the only security for success. It does not seem possible always to exact the presence of an official on the spot. This ought, however, to be secured whenever it is possible. The Government has the intention to remunerate in a suitable degree the officials who accomplish onerous duties, and who render important service. In this respect no absolute rule can be fixed, the rewards must vary with circumstances. “ Special propositions on this head may be sent in; and, in order to + prevent these coming at all times of the year, (which occasions serious loss of time to the Administration) it is desirable, hencefor- ward, to collect them into two despatches, added to’the forms ordered, Nos. 16 and 17 (Circular 806). “Tn justification of the credits opened, the agents stated that in the delay of a month, which occurred in the settlement of accounts, the agents have produced tables with margins of the accounts of the day’s work of the labourers, as a return for the sums put to their account ; for the supplies, they have presented receipted bills, all according to the rules of debit and credit. “The conference at Clermont submitted to the Administration the following question : When the aid granted, according to the estimate of the works, exceeds that estimate, should the extra sum be granted to the appli- cant, and if the expense is less than the allotted aid, should a credit for that extra sum be demanded ? “ Repiy, &c.—The estimate of the expenses of the works can only be an approximate one. Consequently, when the aid is greater than the actual expense, the course to be pursued is to extend the works over a space proportionate to the excess ; or, if that extension is imprac- ticable, to leave unemployed the said excess in money, which will thus be disposable for other works. If the aid granted be less than the expense would be, the works should be reduced by an extent corresponding to the difference of means. “The agents at the conference at Foix proposed that the good or bad execution of the works should be established by a minute declarative of the facts, and to extend the application of this measure to the sanctioned reboisements of communal lands, when undertaken by individuals with the grant in aid. “ Remarks, de. : “Nothing would be gained by the establishment of the good execution of the works by such a minute ; and in regard to the bad execution of the work, it is already prescribed by the regulation to supply grounds for exacting repayment, in whole or in part, of the grant made. “The agents at the conference at Carpentras, in giving account of the means employed to insure the good execution of the works, and the pay- ment of expenses, stated, in regard to delivery of orders, that where this is done it is by small coupons, which has facilitated payment and rectification 198 LEGISLATION ON TORRENTS. of accounts, and has rendered unnecessary the making of advances, and repayments of these, which it is always desirable to avoid in accounts. “ Remark. “To this there is nothing to object, but the fear that it may lead to too great complication of accounts. “ Fourteenth Question. “The allotting of aid having, up to this time, been made as fast as the production of the demands, the Administration have been obliged to leave to each conservator the care of procuring by purchase the seed required, and the necessary plants. It would seem to be more simple, more convenient, more regular, and doubtless more economical, that the Government should centralize the orders for, and the despatch of, these seeds and plants ; Discuss the means of effecting this centralization, if it does not appear to the agents better to leave the ordering of seeds and plants to be done directly, as heretofore, by the agents. “ Opinions, dc., of the Agents. “The agents of the conference at Clermont considered that the centraliza- tion would be very useful, and proposed, for this purpose, the mode of organization which seemed to them most convenient. “The agents of the conference at Foix expressed the same opinion, and presented their proposals. “ At Carpentras the conference expressed the opinion, that, whenever the articles required can only be obtained by purchase, the centralization of the orders for these supplies will be more simple, more convenient, and more regular, but not always more economical: (1) because the seeds purchased are generally inferior in quality to those bought on the spot by the agents themselves ; (2) because the expenses of carriage are great in the one case and nothing in the other. The centralization of orders does not then appear in all cases to offer the advantages to be desired, and ought to be restricted in the one case to species rare in France, such as cedars, Austrian pines, Corsican pines, and in the other, to supplies of seed which cannot be had in the locality. “ Remarks, &e., of the Administration. “The ordering of seeds from merchants at a favourable time for the procuring of the supply, and the ordering of these in large quantities are favourable conditions for obtaining them on the most favourable terms possible. But notwithstanding this, the Administration does not intend to prevent in any way the agents from taking advantage of local supplies. To this end, at the periods for the despatch, of the collective demands for aid, the agents will add to these demands the following information : (1) the quantity of seeds or plants of each kind necessary to meet the said demands, which can be delivered at their destination by the direct care of the conservator through the local resources ; and let the destination of these seeds be stated ; (2) Quantity of seeds or plants presumed to be necessary for the reboisements obligatoires during the season following the despatch of the information. In this let the quantity and species of plants and seeds to be sent by the Government be indicated, also the place of destination and time at which they are required ; (3) Extract from the register of the nursery. Let each conservator state the number of plants required by him and their destinations ; (4) Situation of RESUME OF CONFERENCES IN 1862. 199 the sécheries. And let each conservator report the quantity of seeds required by him, and their destinations. “By help of this information the Administration will be able to give to the trade the necessary orders, and to provide for the direct trans- mission to their destination of the seeds and plants which cannot be obtained in the locality. “ Various Questions DiscussED BY THE AGENTS IN ADDITION TO THOSE SUBMITTED BY THE ADMINISTRATION, “The questions discussed by the agents, in addition to the programme, do not appear to present in general other than purely local interest, and consequently it would be useless to reproduce the whole of them in the present summary. There are, however, some of those questions, which, on account of their wider interest, will be mentioned here. “ Opinions, &e., of the Agents. “The agents of the conference at Carpentras have remarked, that the method of reboisement by strips and by clumps seems a desirable one to practise in cer- tain regions, especially in the departments of the L’Izére and the Hautes-Alps. Clumps of larch would suit well for the high mountain pasture lands. “ Remarks, &c., of the Administration. “This method of reboisement would only be efficacious in so far as it was practised concurrently with the works for improving pasture, and it is necessary to have it kept in mind, that the law for the reboisement of mountains limits its action to works of reboisement properly so called. Besides this, reboisement by clumps would have the effect of extending the defences to embrace very vast areas during the whole period of the first growth of the new plants, and during the successive periods of rebowsement. “The question of the mixture of different kinds of trees in the reboise- ment was under discussion at the conference at Carpentras, but the discus- sion elicited nothing new. “ Remarks, dc. “ There has not been obtained as yet a sufficiency of results to decide this question. “At Foix, an agent said he had tried the effect of sulphur upon seed- beds of laburnum, of ailanthus, and of pines of Aleppo. It brought only to the laburnum a sensible augmentation in vigour of vegetation. The sulphur was only applied at the period of the August sap. The attention of the conference was called to the operation, which might be made the subject of interesting experiments. “ Remarks, é&c. “ The operation of applying sulphur, which is pretty expensive, seems here to have had no other effect than to increase the power of vege- tation in the plants of the seed-beds. It does not appear certain that important advantages result from its use. It will not be with- out use, nevertheless, to make experiments in this direction when a good opportunity may present itself. “A proprietor of the department of L’Arie¢ge had proposed to the Administration to grant to him land for the establishment of a central place for trials, experiments, and observations, in forest, pastoral, and hydrological matters, in relation to the reboisement of mountains, 200 LEGISLATION ON TORRENTS. “ The agents deemed that such a field of experiments, however useful for the district in which it might be placed, would not be capable of furnishing certain information for other regions, and that, in this point of view, the proposed establishment does not present the promise of adequate general interest. “ Remarks, ke. “The Administration shares the opinion of the agents at the conference at Foix. “ Desrres EXPRESSED BY THE AGENTS ASSEMBLED IN CONFERENCE. “The Agents at the conference at Foix expressed the wish that the Administration of Forests should be ‘charged with the mise en valeur, or improvement, and the reboisement of the communal lands situated on the- mountains. “The execution of the law on the mise en valeur of the communal uncul- tivated lands lies with the prefects. There is nothing to prevent the execution of such works of this character, as have for their object reboisement, taking place under the care of the forest agents. It is thus that the law in question is applied in the department of the Vosges. The conservators will consider whether they ought not in this matter to advise with the depart- mental administrations. “The agents at the conference at Carpentras have expressed the following wishes : (1) That in future the programme of the conference should be sent to each agent at least a month in advance ; (2) That the members appointed should bring with them samples, models of instruments, &c. ; (3) That they should put down beforehand in writing, as far as possible, their answers to the questions on the programme, and their observations. “ (Signed) H. Vicarre, Director-General of the Forest Administration. “ Paris, January 10, 1862.” The following is an Abstract of Report of operations in 1862 :— In 1861 the expense of the reboisement of the mountains was settled as follows :— Subventions for rebowsements facultatifs, or sanctioned opera- tions, granted to communes and private individuals for labour upon Crown lands, for nurseries, for sécheries (or places for collecting and drying seeds), for keeping up the works, and for various kinds of labour, Frances, 548,855,30 Support of agents and overseers, 3 46,718.94 Indemnities to agents, overseers, and assistants, a 42,439.40 Francs, 638,013,64 A. Reboisements Facultatifs. In 1862 the demands for subventions have been as follows :— By communes and public establishments, 730 \ 1498 By private people, 698 - Of which only 40 have been rejected, as not falling withinthe scope of the law. These demands came from 39 departments in all. The areas reforested were, for what had been done by 742 communes and public establishments, 5,774 58a ; by 394 private individuals, 1,714u 154—total, 7,488u 73a 00. It was in the departments of Puy-de-Déme and of Vancluse that there was the largest extent of communal reboisements. ABSTRACT REPORT 1862. 201 Subventions in money and in kind, amounting to 280,000 francs, representing about two-thirds of the total expense of the works, The reboisement of private property has been most extensively carried out in the departments of the Gard and the Dréme, where the subventions amounted to 70,000 francs, representing about 40 per cent, of the total expense of the works. The discovery, it is stated, is being made, that rebotsement is an opera- tion much more fruitful in immediate advantages than had been generally believed, : The report cites two examples of these advantages : A commune possessed a district of 64 hectares covered with heath, which had not been sold, though in 1844 offered for sale at 7000 francs, At this time a sowing of pin sylvestre was undertaken, at the expense of the municipal chest ; there was little additional expense ; and now this district is valued at more than 70,000 francs, Another commune possesses a wood of 47 hectares in extent, planted with pins sylvestres about 15 or 16 years old. Lately a thinning was effected, which produced 16,000 francs. These well-known facts have not a little contributed to the favour with which the works of rebotsement are regarded in the departments in which they had been carried out. Joint stock companies, or associations of capital, are now very advan- tageously employed for the exploctation of different branches of industry. The acquisition of mountain districts on generally very moderate terms, and their replenishment with wood by the help of large subventions, seems to form the basis of a speculation which is both productive and exempt from risk of loss. The restocking of the mountain Crown lands had extended, in 1862, over 1866uH. 03 ares, at an expense of 146,747 fr. 51 ct. B. Reboisements Obligatoires, or Enjoined Reboisements. In all cases in which public safety demands the creation of such hinder- ances as reboisement can offer to the irregular action of rivers or floods, or to the crumbling of the ground, and where the safety of the inhabitants, the condition of the roads, and the culture of the lower declivities, are most threatened by torrents and avalanches, the law has commanded the formation of woods; the extent of these is in proportion to the hydraulic effects they are designed to produce. The Administration has carefully considered the condition of the dis- tricts where veboisement seemed to be most urgently required. These careful inquiries in 1861 and 1862 extended over 21 departments, and gave rise to the origination of 269 enterprises, comprehending 136,756 hectares. 89 undertakings, extending over an area of 59,833H. 28a. have been offi- cially inspected. The projects have encountered a good deal of opposition, “Tt is necessary clearly to define the character of this opposition,” says the Director General of Forests, ‘in order to exhibit the influence of the operation of reboisement upon the condition of the mountain population. “Tn most cases the herds of cattle do not belong to the poorer inhabit- ants. The flocks of sheep belong toa certain number of local owners, who make all they can out of the communal lands, or to people from a distance, whose immense flocks, known by the name of transhumant flocks, every year cover the mountains leased from the communal bodies, at usually a very moderate rent. A + 202 LEGISLATION ON TORRENTS. “The operation of reboisement, far from introducing new restrictions into the already straitened circumstances of the poor inhabitants, would, on the neotrary, be a source of numerous advantages. Without mentioning one of these advantages which can only be realised in the more or less distant future, there can be pointed out as an immediate and direct result, the unusual comfort diffused over these poor districts by the money devoted to the execution of the works in the form of wages, purchase of seeds and plants, and other outlays of various kinds. “ There is reason to think that the mountaineers, with their characteristic mental quickness, have already come to appreciate the operation of reboise- ment, and that the opposition which has arisen in several cases is only an expression of personal and isolated interests. “It is, moreover, only through mistake that the pastoral population takes alarm at the undertakings of the Forest Administration, the greatest number have been in favour of this industry. Besides the immense tracts known by the name of pastoral mountains, which lie above the zone of forest vegeta- tion, and of which the destination indicated by the nature of things cannot be modified, the actual sheep runs are in many cases not only preserved but improved from the double point of view of the pastoral interest and the preservation of the turf.” Nearly all the commissioners charged with the direction of these inquiries have earnestly approved of the projected reboisement, and in all cases the special commissioners, the Councils of the Arrondissement, the General Councils, and the prefects have adopted these projects. Besides, the General Councils have voted subsidies in favour of the reboisements. These subsidies, 20,000 francs in 1860 rose to 40,000 francs in 1861, and to 71,000 in 1862. The gradual increase of these sums, more than their absolute importance, iy an indication of the increasing movement of public opinion in favour of the operation. Reboisements obligatoirs, or enjoined reboisements, had extended in 1862 into three departments, and into seven périméters, or defined areas, of over 2061 hectares 87 ares, and has cost the State 69,576 francs 21 cents. ne the reboisements effected in 1862 amount in all to 11,416 hectares ares. C. Sécheries and Nurseries. The reborsement in 1862 has been effected, by means of sowings, upon 8344H. 264.—by means of planting, upon 3072H. 37a. For the sowings 95,403 kilogrammes of the seeds of different trees have been used. For the plantations there have been used 22,137,500 plants of different sorts of trees, besides those transplanted from the woods. The pin sylvestre, or Scotch fir, épicéa, or Norway fir, and the larch, have been most generally employed. Other trees have also been used—as the oak, the Austrian pine, the Mugho, the Aleppo pine, the cedar, the ailanthus, which are introduced gradually in proportion as new experiments are tried. The selection of trees has generally been directed by local indications. Four sécheries were formed in 1861; two others were established in 1862. These supply from 15,000 to 20,000 kilogrammes of seed, corres- ponding to the reboisement of 2000 hectares, Tne outlay in 1862 amounted to 38,515,24 francs. ABSTRACT REPORT 1863. 203 The Administration has, morover, in 1862, set agoing the collecting of seed in the Crown forests, and has collected considerable quantities at a very moderate expense. In 1861 there had been formed 473 nurseries, 330 hectares in extent, and capable of supplying about 60 millions of plants per annum. In 1862 there had been formed 359 new nurseries, covering 272 hectares 96 ares, capable of producing annually about 40 millions of plants. Many of these nurseries are of small extent, and are designed to supply plants for restocking the immediate vicinity. But in several cases central nurseries of considerable importance have been formed, situated in suitable districts, which had been bought or rented with a special view to the work in hand. These nurseries have been the object of the greatest care, they are 14 in number, and are spread over ten departments. It is calculated that 5000 hectares is the extent annually reforested by means of planting, and that 40 millions is the necessary supply of plants. At the market price this quantity of plants would cost 240,000 francs. In 1852 the expense for the formation of new nurseries, and the keeping up of the old ones, amounted to 153,772 franes. D. Administrative Measures, A new district under a forest conservator has been formed. Annual conferences, attended by those taking a part in mountain reboisement, have been instituted. The Director of the Government School of Forests has been appointed to visit the works of reboisement in the Pyrenees, the Alps, and the moun- tains of Central France. The object of this visitation is to encourage the efforts of those employed, to secure everywhere good methods of culture, and to report to Government upon the execution of the works and the result obtained. According to the preamble to the law of 28th July 1860, the expense of rebotsement was estimated at 180 francs per hectare. In 1861 and 1862 160,055 hectares 63 ares had been reforested. The expense during these two years had been 1,738,000 francs, or 180 francs per hectare, without taking into consideration the part of the above mentioned expense incurred in the preparation for enjoined reboisements, the formation of sécheries, the purchase of Jand, and other expenses not directly belonging to the work of replanting, properly so-called. The expense per hectare reforested will be still further reduced through use being made of the extensive resources supplied by the nurseries and sécheries, and of experience acquired by practice in the execution of the works. AxssTRacT OF REPORT FoR 1863 :— According to the detailed accounts of expenditure on the work in 1862, the expense has been as follows :— Subventions, - Frances, 350,000,00 Purchase of Property, 5 ee 231, 300 Execution and Superintendence of the Works, ss 761, "957, 31 eee Total Francs, 1,125,188,31 204 LEGISLATION ON TORRENTS. A. Reboisements Facultatifs, or Sanctioned Reboisements. Subventions have been granted to 450 communes, or public establish- ments, and to 983 private individuals. These reboisements are extended over communal lands, 7,073H. 24a. ; private property, 2,157. 05a. ; crown lands, 1,750n. 88a. ; total 10,981x. 174. Outlay, at the Government expense, 595,000 francs, besides the expense of keeping up the sanctioned reboisements of former years, 81,800 francs. When requested by proprietors, the Forest Administration have carried on the work of reboisement under the superintendence of its agents and guards, and they will continue to keep them up and develope them, so far as possible, till success appears assured. The works have been spread over 40 departments. The report specially mentions an experiment of reboisement in the Crown forest of the Luberon, situated on the formation called neocomien, belonging to the lower portion of the chalk formations, where the bare places are covered by enormous heaps of rocks, burnt by the sun, and entirely destitute of vegetable mould. Such is the district of which the forest agents have not been afraid to attempt the reboisement. Nothing has been neglected to ensure the success of this bold enterprise. After several attempts at plantation, which proved either fruitless or else too costly, the agents fixed on the method of replenishment by sowing, principally with the seed of the pine of Aleppo. The small quantity of vegetable mould still remaining between the rocks was gathered together into narrow ridges, and prevented from falling down by layers of stones. Upon soil prepared in this manner the sowings were most successfully effected. In the month of September, after the trial of an exceptionally dry and hot summer, the young plants appeared quite flourishing. Toone who has seen the sowings of Luberon, (says the report) no reboisement will appear impossible, Among private individuals the taste for forest improvement seems to have a tendency to increase wonderfully. The number of private pro- prietors who had received subventions, which was 394 in 1862, ‘1 1863 amounted to 983, B. Reboisements Obligatoires, or Hnjoined Reboisements, On the 1st January 1864, the districts comprehended in the Government undertakings were to be found in 23 departments, Digests have been prepared of 264 enterprises, of which 77, embracing about 60,000 hectares, have been approved, with decrees declaring their public utility. The works of rebotsement then in course of execution in 26 circles ex- tended over a surface of 1,853n. 57. The expense has been 154,850 francs, besides 13,100 francs for keeping up the works already effected. This outlay, however, is only a Government loan in terms of Articles 8 and 9 of the law of 28th July 1860. Tn cases where direct reboisement did not present a sufficient probability of success, because of the absence of vegetable mould, it has been preceded by the restoration of the soil, by means of planting or sowing herbs or bushes. The principal plants growing spontaneously on the mountains are juniper, barberry, Vargoussier, l’amélanchier, which are chiefly found in the rockiest places, white fescue grass, whose luxuriant tufts appear on the steepest parts of the ravines, ‘the sainfoin and lucerne, the long matted roots of which are well fitted to retain the soil upon the slopes. ABSTRACT REPORT 1863. 205 A considerable number of rustic barriers have been formed on the upper branches of the torrents. Instead of a large work of art constructed at the mouth of the ravine, which nearly always gives way, the system of defence consists in the formation of a number of dams across its ramifications throughout the upper portion of its course. The small furrows which form the highest branches of the torrents are dammed by simple faggots fastened with stakes. In the larger branches, and where the presence of rocks or any other circumstance appears to favour the construction, there are formed dams made of hurdles and boughs, or walls of stones placed one upon _. another strongly attached to the banks, or by rude carpenter work, the whole being completed by interweaving quantities of willow and osier wands into the banks, and into collections of earth which accumulate above the barricade. “The success of these simple and economical works is remarkable. The water, arrested everywhere in its descent, falls with much less violence and rapidity ; a great part of the materials which it bears along are stopped by the barricades, and no longer spread themselves over the villages and lands situated at the foot of the mountain; finally, the accumulation of these materials, joined to the quick growth of the willow wands, tends to efface the effects of the torrent between the successive barricades, and in some measure to lessen the torrent by stopping up the ramified furrows of which it was composed.” Total extent of rebovsements effected in 1863, was 12,8345, 74a, C. Preparatory Works. The question, which of the two methods of replenishment, sowing or planting, should be preferred, does not admit of absolute solution. “In planting, two principal dangers are to be dreaded : The swelling up or upheaval of the soil in spring, produced by the alternations of frost and thaw, the effect of which is to lay bare the roots, and even to throw out the plants,—and the drought in summer. These dangers may often be averted or escaped, by placing, when circumstances permit, at the root of the plant one or two stones, intended at the same time to hinder the swelling of the soil and to keep the surface of the ground cool. When the trees are planted amongst herbage, after a turf is cut, for the purpose of planting a young tree, it is cut in two and placed at the root, either in the position which it occupied before the operation, or turning the grass side towards the ground. “ Autumn has been preferred for planting, spring for sowing ; but experi- ence has proved that sowings completed after the greatest heat of summer are the most successful; the young plant appears before the cold, then comes the snow to cover and protect it till the return of spring ; it then resumes its scarcely interrupted growth, and when summer arrives it is robust enough to resist the heat.” D. Nurseries. Since the beginning of the enterprise of the reboisement of the moun- tains, Government has felt the necessity of getting rid of the obligation to have recourse to purchase, because the outlay is great and the produc- tions are not always to be depended upon. The harvest of the fruit of this foresight is now beginning to be reaped. Two kinds of nurseries have been formed. (1) Small nurseries, scattered over the district where the reboise- 206 LEGISLATION ON TORRENTS. ments are of small extent ; (2) More important nurseries, intended to supply subventions of plants to communes and to private individuals, as well as the reboisements obligatoires of specified périmétres. The first-mentioned nurseries, containing less than 50 ares, are 355 in number, and cover in all 41 hectares 42 ares. The second, of greater extent, containing more than 50 ares, are 97 in number, and cover in all 144 hectares 72 ares. The expense of the nurseries, for establishment and keeping up, has been 163,000 francs. The following is an account of the expense and returns of two nurseries of the second class, those of Arpajon (Cantal) and of Bourg (Ain) :—The first, 7 hectares 43 ares in extent, has cost in all 51,252 fr. 60 ct. It has produced since its formation 4,365,310 resinous and broad-leaved plants, of the value of 42,712 fr. 60 ct., according to market value. The expense of keeping up will be from 10 to 12 thousand francs annually, and the return from 6 to 8 millions of plants, which, at an average price of ten francs per thousand, represent a value of from sixty to eighty thousand francs. The second nursery, 4 hectares in extent, has required an outlay of 29,107 fr. 53 ct., and it has supplied 2,050,000 plants, 20,000 francs in value. Its keeping up costs annually from 5 to 6 thousand francs, and it produces about two millions of plants, valued at 20,000 francs. E. Co-operation of the Departnents. The General Councils have approved of the greater part of the projects submitted to them, In 1863, 35 departments have granted sums amonuting to 98,000 frances. These subsidies have been in 180, 20,000 francs. ” 9 ” 161, 40,000 2”? ” ” ” 162, 71,000 ” ABSTRACT OF REPORT FoR 1864 :— In 1863 the expense of the reboisement of the mountains amounted to 1,316,652 fr. 15 ct., apportioned as follows :— Subventions to communes, to public establishments, and private proprietors, - Franes, 494,000.00 Purchase of land, - 5 23,879.13 Execution and superintendence of work, - _ 798,773.02 Total Francs, 1,316,652.15 In 1864 the expenses were, - i 1,401,822.48 A. Reboisements Facultatijs, or Sanctioned Reboisements. Tracts of land belonging to communes or public establishments.—458 com- munes or public establishments have received, in 1864, grants of seeds and plants, or of money, amounting to 352,210 francs 15 centimes, The tracts reboiséd with the help of these grants were, 6,164 hectares 32 ares in extent. According to results determined by forest officers, the sowings and plantings. succeeded in at least a proportion of from 60 to 80 per cent, Land belonging to private individwals—Government had in 1864 granted subventions to 739 private individuals for the reboisement of mountain terri- tory, covering an extent of 1,601 hectares, dispersed among 28 departments. ABSTRACT REPORT 1864. 207 Crown tands,—In the departments where the State possesses bare moun- tain territory, the Forest Administration has set the example of reboisement by sowing or planting every year areas more or less considerable. 1,834 hectares 70 ares of this kind of ground has been rewcoded in 1864. It is chiefly in the department of Ariége that the restockings of this kind have taken place during several years with remarkable success. Altogether the reborsements facultatyfs of evéry class, in 1864, covered 4,743 hectares 90 ares. B. Reboisements Obligatowres, or Enjoined Reboisements. At the end of 1864 the number of projected enjoined reboisements were 322, covering a total extent of 168,300 ares. Of this number, 84, covering 61,814 hectares, have been at the same time subjects of a decree declaring them to be of public utility, In the course of the same year, works have been executed in 65 péri- métres, These works have consisted of redoisements properly so called, the keeping up of reboisements effected in preceding years, sowings or planta- tions of herbs or bushes, construction of dams, lopping trees, and enclosures. These have cost 249,000 francs. The Government in 1864 hag only had recourse to expropriations in the cases of two tracts of ground, extending to 25 hectares, for which the price paid amounted to 9,476 francs 47 centimes. , It is with the utmost reluctance that Government makes use of the privilege accorded by the 2nd paragraph of Art. 7 of the law of 28th July 1860. Since the law has come into operation, there have only occurred some three cases in which it was needful in the public interest to proceed to ex- propriation. C. Conferences. Conferences held in cantons to determine what lands should be re- planted have continued to discharge this duty in a manner the most satisfactory. D. Résumé of Work executed in 1864. The total sum of reboisements effected in 1864 embraces an area of 12,193 hectares 32 ares. E. Kinds and quantities of Seeds and Plants used in 1864, and ways in which they have been apportioned. Of the 12,193 hectares 32 ares rewooded in 1864, 7632 hectares 44 ares have been sown with seed ; and 4559 hectares 88 ares have been planted. The principal kinds of trees thus used have been, as in years preceeding, le pin sylvestre, or Scotch fir; Pépicéa, or Norway fir; le pin maritime, or maritime pine ; Ze méléze, or larch ; le pin noir d’Autriche, or Austrian pine ; le pin laricio, or Corsican pine ; le pin & crochets, or Mugho pine ; le sapin, or silver fir; le chéne, or oak ; le chdtaigner, or chesnut ; le hétre, or beech ; le fréne, ov ash. It is with the greatest reserve that attempts have been made to introduce other kinds of tree, which are not indigenous, in such districts as have been rewooded. Of the 161,260 kilogrammes of seed used in 1864, 137,028 kilogrammes have been supplied by sécheries domamials. But the Administration has not found any great advantage in preparing their own seeds. 208 LEGISLATION ON TORRENTS. In regard to plants, of 55,740,000, 49,334,000 have been reared in nurseries belonging te the State; and the others, 6,408,000 have been obtained from nurseries belonging to private parties. The expenses of all kinds incurred in maintaining the State nurseries has amounted, in 1864, to 175,892 francs; and the value of the plants supplied from them in the course of the year, estimated at 6 francs per 1000, which is much below the average market price, amounts to about 300,000 frances. It is of some importance to add that, in regard to adapta- tion to their destination, the quality of the plants supplied from the State nurseries is in general much superior to that of the others; and, in the report it is added, there is reason to hope that the Administration will soon be in a position to dispense entirely with having recourse to purchase for the supply of plants. The principal nurseries of the Administration collectively cover an area of 257 hectares 34 ares, and can supply 93 millions of plants per annum. F. Co-operation of Departments. The amount of subventions voted by the departments in 1864 is nearly the same as in 1863, being 81,104 francs, as against 78,000. The following is a general résumé of what was effected in these first four years of the enterprise :— ; In these years there were replanted with woods 41,083 hectares 26 ares. Of these there were reboisements facultatifs, or sanctioned reboisements, on property belonging to private proprietors, 6056H 134 to communes, - 216655 84a to the domaine, 6853H 564 ; 34575H 53a Reborsements obligatoures, or enjoined reboisements, 65078 73a 41083H 264 The accomplishment of the work cost the State, in 1861, 638,013 fr. 64 ct. ; in 1862, 1,125,188 fr. 21 ct.; in 1863, 1,316,652 fr. 15 ct.; in 1864, 1,401,822 fr. 48 ct.,—total 4,481,676 fr. 48 ct., being, on an average, 102 francs per hectare. Thus far all seems to have gone on satisfactorily. Every thing had been done to carry public opinion, and the sympathies of those who were more immediately affected by the operations, with the enterprise. But it becomes necessary at this point to advert to the results of this commendable endeavour, and the supplementary legislation which this necessitated. From the first the work had been prosecuted with vigour, and it had the support of many of the more intelligent inhabitants of the district ; but after a time, as may be seen from these reports, a reaction began to mani- fest itself, and this became at length developed into strong opposition on the part of many. “ As may always be expected,” says Cézanne, “ difficulties which had not been taken into account began to make themselves apparent when the work was commenced, The word reboisement frightened the pastoral communities ; there was promised to them herbage growing under the trees in about EXPOS DES MOTIFS OF LAW OF 8TH JuNE 1864, 209 twenty years; but in awaiting this how were they to support the flocks, which supplied their only income? ‘The operation,’ cried they, ‘is a hey injustice ; they are ruining the mountains in order to enrich the plains.’ “The Administration saw that there was some foundation for this com- plaint, and they resolved to do what was right in the case; but the law spoke only of reboisement—their powers, and the funds placed at their disposal, related only to this; and something must be done to meet the case. “It was thought at first that this might be effected by the law, Sur la mise en valeur des biens communaus, for the improvement of communal pro- perties. The greater part of the lands to be replanted being communal lands, it was thought practicable to unite the two objects, and combine the two funds for a common action, and a mixed commission was nominated by the three ministerial departments interested ; but it was found that the two laws which they sought to combine in joint action had two very different objects: the law on reboisement had for its object to secure the public safety, the other to promote the national wealth; the former acted on decrees with credits and subventions, the second by prefectoral resolutions granting simple advances ; by the first the Agents des Eaux et Forets were charged with the reconstitution of communal property, to carry out the second the officials of Les Ponts et Chaussées labour to convert communal into national or personal property.” The Mixed Commission soon reported its powerlessness, and the Govern- ment had to follow up the law in regard to reboisement with one relative to gazonnement, The following is a translation of the Zuposé des Motifs, which accompanied the draft of this law, addressed to the councillors of State charged to support it before the Corps Legislatif :— “‘ GENTLEMEN,—When the law of the 28th July 1860, on the reboise. ment of the mountains, was submitted to the consideration of the Corps Legislatif, the honourable reporter, in the name of your commission, expressed himself in these words :— ““Tt may be well, then, to recognise the fact that the deboisement, or destruction of woods on our mountains, is not the only cause, or even the principal cause, of the disasters produced by the ravages of the waters, Along with this, as still more hurtful, must be classed as a disturbing cause degazonnement, or the destruction of herbage. ; “«Tn like manner, reboisement alone is not enough to remedy these evils, It would be impossible to replant with trees all the bare mountains, on account of the great expense. It would also be useless, as keeping up the turf is a sufficient preservative, the benefit of which has been proved by experience. It would also be difficult, looking at it from the stand-point of the wealth of the country, as it would substitute comparatively profitless forests for the magnificent pasturage, the destruction of which would ruin the population of the mountains. “But it is not the less true that, in conjunction with gazonnement, reboisement will have a most happy effect. “«The present law will only produce all the good effects which may be expected when it shall be supplemented by gazonnement, 2A 210 LEGISLATION ON TORRENTS, “¢The experience and the investigations of engineers have shown that in certain cases it is indispensable to arrest a daily increasing evil, for only in this way can possibly be preserved certain districts unfitted for pasturage, and threatened with approaching destruction. Reboisement will create a great protection, preserving even the pasture lands, regulating the flow of the water, and preventing the formation of avalanches, and exercising certain specific effects during atmospheric perturbations. “¢The measure which is now proposed is truly a law for the public welfare, and has a right to all our sympathy ; but it will not produce all the good that may be expected, until it shall be supplemented by measures for the protection of the herbage, and by measures repressing the increasing evils of depasturing. “© The commissioners appointed by you pray earnestly for these measures, regarding which they have no power to take the initiative.’ *« Goverment has not overlooked this view of matters in the preparation of the law of 1860. The Exposé des Motifs, or reasons assigned for this law, explained to the legislative body the various reasons which at that time led the Government to determine not to extend the action of the law to the restoration of herbage. One reads as follows, at page 17 :— ~ «¢We do not conceal, that, even looking at it from the point of view of hydraulic results, which is the stand-point of the law, the restoration of the herbage is fitted to give important help to reboisement. At the same time, it does not appear possible to extend so far the operation of the pro- posed measures, and that for several reasons. “¢ First, the financial resources which are at command are not adequate to meet the expense of the reboisement which it is desirable to encourage and execute, unless they be laid out with the greatest economy and wisdom ; no part, therefore, should be diverted to works of a different nature, or inferior utility. “<¢Second, reboisement, where executed intelligently, having solidified the soil, will also, in a certain degree, promote the natural restoration of herbage in certain places. “¢ Third, there is room to hope that, having before their eyes the reborse- ment executed by or under the influence of Government, communes, to whom depasturing offers immediate and individual advantages, will be easily induced to undertake for themselves the restoration of their pastures, now that it has become more easy and sure of success. “Finally, the legislative body is engaged on a special law for bringing under culture communal lands, which will’ serve in cases altogether excep- tional as a last resource.’ “The first reason which we have adduced still subsists; it is certain that it would be impossible to proceed with reboisement and with gazonne- ment simultaneously, and to a sufficient extent, with nothing but the resources created by the law of 1860; but the hindrances may speedily disappear should Government approve of the proposals which we shall shortly have the honour of presenting. “ As to the two last reasons, they rest upon conditions which it must be confessed have not yet been confirmed by experience. We shall later explain the causes which are opposed to the realisation of our hopes. “It is right that we should furnish the Corps Legislatif with a summary of the practical results of the law on reboisement, The success of this law may be confidently affirmed. EXPOSE DES MOTIFS OF LAW OF 8TH JUNE 1864. 211 “ Rebotsements facultatifs, that is to say those set a-going by the simple encouragement of State subventions, have extended,— In 1861, to - 3,237 hectares. In 1862, to Tate In 1863, to 9320 5 “ Reboisements effected on the Crown lands have replanted,— In 1861, 1,402 hectares. In 1862, 1436, In 1863, 1,750, “ As regards reboisement obligatcires, that is to say, what is done in the périmétre, or boundary, the replanting of which has been pronounced necessary for the public welfare, the operations have been necessarily retarded by the fulfilment of legal formalities, but investigations and instructions have been carried on with activity. “ At the end of 1863, 264 undertakings, comprehending 140,000 hectares, were made the subjects of special consideration, and 77 had been the subject of special decrees declaring their public utility. The operations were being executed in 26 périmétres, and over an extent of 1,853 hectares. “ At least 40 Departments are profiting by the operation of the law. ‘Several General Councils of Departments have desired to take part in the Government works. The sums voted have been,— 20,000 francs in 1860 40,000 , » - - 1861 7 1,000 , - 1862 92.000" 5. 1863 “The import of such a constant and rapid progress has not escaped the notice of Government. The net cost of the operations has not been less satisfactory. “The reasons assigned for the law of 1860, inspired by a very decided wish to avoid all illusions and chimerical promises, fixed the average expense of the work of repeuplement at 180 francs per hectare. What has been done in the average expense has not exceeded 108 francs, and the benefit of the law may thus extend to other and more extensive districts. “ Government has all along met with the greatest sympathy from the General Councils of Departments, Councils of Arrondissements, and Special Commissioners. “But now, as we approach a very important and very delicate point—the moral disposition of the population towards the measures taken to carry into effect the law of 1860—we meet facts which have induced Government to think that it is opportune, and perhaps necessary, to complete this law in accordance with the wishes expressed by the Commission of the Corps Legislatif, at least in so far as relates to the communal pasture lands. “The aim and consequences of the law relative to mountain reboisement has been but imperfectly understood and appreciated by Municipal Councils, and by the inhabitants of the communes most interested. “Those who have the rights of pasturage, accustomed to,the slender in- come derived from depasturing—and it must be admitted sometimes too poor to do without this, are disturbed by measures which temporarily restrain their individual privileges. Moreover, seeing that Government occupies itself exclusively with works of reboisement, they attribute to it the design of everywhere substituting forest for pasture, so as to progressively accom- plish the suppression of depasturing. 212 LEGISLATION ON TORRENTS. “The consequences have been these : on one hand, a pretty large number of decrees proclaiming the public utility of the measures have been published, contrary to the advice of the Municipal Councils and to the wishes expressed by witnesses at the inquiry ; on the other hand, the communes have refused to make the small sacrifices which would have been necessary for the restoration, in a future more or less distant, of pastures of which they believed they were destined to be deprived altogether. “Independently of these obstacles and these misunderstandings, we ought to add, that many communes are to be met with which are really too poor to undertake the operations at their own expense, however inexpensive they may be, or to endure being deprived, even for a short time, of the incomes which a number of them derive in one form or another. from the communal pastures. ‘Tn this predicament Government has seen the necessity of intervention, and the pressing duty of enlightening the inhabitants, of reassuring them, and especially of meeting their real necessities and their just desires, by seeking to make compensation for the diminution of their privileges, looking to the valuable possessions of the pastures. “ Before having recourse to a new law, Government has tried what effects would be produced by the combined co-operation of the law Sur la mise en valeur des biens communaua, with the law on reboisement. “ A High Commission has been created ‘for the purpose of finding out the best way to make the two laws co-operate towards a common end, and with the help of their mixed character to smooth away the difficulties which may arise between the two Ministerial Departments entrusted with the execution of these two laws—that of agriculture, commerce, and public works, and that of finance’. “This Commission has acknowledged the impossibility, or at least the extreme difficulty, of reaching the same end with the two instruments at its disposal. And in order to attain this end it is necessary, in the first place, to find out the mountain districts, the consolidation of which is demanded by the public interest; to distinguish between ground which must be reboiséd or replanted with woods, and ground which must be segazonnéd or planted with turf ; to mark out the périmétres with reference to these; and in these périmétres to determine the number and form of massive woods which are to retain the floods and protect the pasturage. It is necessary that the enactments prepared by Government should be submitted, as a whole and in their harmony, to the various authorities, to the Councils, and to the Com- missions, whose duty it is to give their advice in regard to the instructions issued. It is necessary that the subventions furnished by the State and the demands for local subsidies should be in proportion, on the one hand, to the public utility of the enterprise, and, on the other, to the advantages which would result to the local population ; finally, it is necessary that the temporary privation of privileges should in certain cases be compensated by grants of money, at least to the poorest communes. “Tt may be seen that this combination of circumstances, or conditions, can only be secured through a double operation—by means of two parallel codes of instructions, by means of two administrations, and by the applica- tion of two distinct laws. The difficulty is not wholly related to the truth, that to be useful an operation should have a single aim ; but also to this, that. the two laws, while presenting incontestable analogies, are, nevertheless, distinguished by notable differences. EXPOSE DES MOTIFS oF LAW OF 8TH JuNE 1864. 213 “The principal stand-point of the law of reboisement is the public safety, the regulation of the water-flow, and the protection of the low grounds. Economy is only secondary. “The stand-point of the law relative to bringing communal lands under culture is more especially economy, the improvement of the com- munal patrimony, the increase of the general food supply, and the increase of the municipal revenues. “ The formalities prescribed by these two laws are analogous ; but they are not identical. “ According to the law of reboisement the initiative should be taken by the Central Government ; according to the law Sur la mise en valeur des biens communaux the initiative is to be taken by the prefect. “The law on rebotsements sets agoing a very complicated machinery, more especially the special commissions ; the law Sur la mise en valeur des biens communaus does not require the interference of these commissions, ‘Tn another relation the law on reboisement offers two kinds of encourage- ment—fixed subventions and recoverable advances; the other law offers only recoverable advances. “Finally, the law Sur la mise en valeur des biens communaux, conform- ably to the nature of its aim, tends to withdraw the p-operty improved from the possession of the public ; it formally authorises the State to enact that the improvements shall be consolidated ; the law on reboisements, on the contrary, promises to throw open the ground for pasture whenever the trees are old enough, and the result expected from regazonnement is designed to be, as we have already said, to restore to the possessor a more valuable in the place of a more extended privilege. ‘“‘ These differences will explain how it is the High Commission has been led to think that there is no hope of great and regular development, the necessity of which is now clearly shown, through the conjoint operations of this double initiative, of these double instructions, and these different tendencies, whatever may be done to organise the simultaneous application of the laws. The High Commission has unanimously acknowledged that the only practical efficacious means of obtaining the desired combination of gazonnement and reboisement in the périmétres mixtes, is to entrust the initiative and instructions to be given, and the execution of these, to one single administration under identical conditions, with the performance of the same formalities, with a single enc in view, and that that which is arrived at by the law of reboisemenf, and of which a law simply supple- mentary to this would easily ensure the attainment. “ Government has adopted the proposal of the High Commission, and, the principle once admitted, the drawing up of the scheme presents few diffix culties, Nothing is needed but to extend to the renewal of pasture in the périmétres mixtes the arrangements already adopted for the forest repeuple- ment, and to add to the funds created by the law of 28th July 1860 the necessary supplement. “ Gentlemen, we have very little to say upon the different articles of the scheme, and we shall advert to them here very cursorily. “ Art. 1, in reproducing the definition of art. 4 of the law of 28th July 1860, aims at defining the object of the new law, and at demonstrating that it is only a supplement to the older one. And it should be thoroughly understood that the action of the Finance Department can never take the place of the Agricultural, Commercial, or Public Works Department ; that 214 LEGISLATION ON TORRENTS. the Forest Administration will only exert its power to investigate or to execute operations for restoring the sward on hilly ground, looking exclusively to the public utility in the regulation of the water-courses, and the consolida- tion of the soil—that is to say, in conditions identical with those which led to its being invested with the power of encouraging or executing the reboisements, “ Art, 2, for the arrangement of preparatory formalities, refers simply to the law of 28th July 1860 ; it could not do otherwise, for in most cases the question is, how to accomplish the formation of mixed périmétres composed of woods and tracts of new turf; the directions ought to be combined for this double object, and consequently should be subjected to the same regulations. “A temporary arrangement authorises the Forest Administration, in regard to ground included for the first time in the area of rebovsement obligatoire, to substitute operations for renewal of the turf for operations for reboisement in such measure as they my deem fit. “ Art. 3 relates to art. 9 of the law of 28th July 1860. This last article enacts that, in cases where the State executes operations of reboisement upon communal lands, the communes may relieve themselves of the burden of repayment by giving up the proprietorship of half of the lands rebovsed. It has appeared that, when operations of regazonnement only are in question, the proportion of one-half is nearly always too great, taking into considera- tion the expense of the work. Hence, an srrangement by which the communes may always get exemption, by giving up land in proportion to the advances made for their benefit. “ Art, 4 fixes the different executive measures which should be specified by regulation of the public administration, This statute should determine the mode of certifying the advances made by the State, and the measures necessary for securing the repayment of these; it should also lay down rules for the allocation and settlement of grants of money which it may be necessary to allot, to communes which are too poor to submit to even a temporary deprivation of pasture, though in the view of its improve- ment,—erants of money, which, besides in certain cases, will constitute the greatest part, or even the whole, of the expense of restoration, and which should only be granted in cases of absolute necessity by a decree declaring the public utility of the measure. “Finally, Art. 5 creates the financial resources required for the operation of the law. The Government is referred, for the specification of the nature of these, to the law of 28th July 1860, and in proposing to obtain these resources from extraordinary fellings it has only followed the line of action ‘indicated by your Commission four years ago. “Such, gentlemen, are the principal arrangements of the Project de lot which we have the honour to submit to you ; they have a special reference to the mountain lands, because the Forest Administration, with whom the execution of them will lie, has only, in what relates to the regeneration of pasture lands which are not wooded, for its work, to carry out measures complementary to the law Sur le Reboisement des Montagnes ; they have also a special reference to communal lands, because the improvement of meadows belonging to private proprietors have not appeared of a character to warrant either the application of coercive measures, or the employment of the funds of the State; these arrangements do not the less apply to numerous localties, and to areas of very great extent; they will produce Law oF 8TH JuNE 1864. 215 no small effect by their physical action, and they will not be without interest, in more than one locality, in regard to their influence in pacifying the mind. We hope, gentlemen, that they will meet with your approval.” The draft, or Projet de loi, with such modifications as were proposed by the Commission to which it was submitted, was adopted by a unanimous vote of the Corps Legislatif, and was issued in the following terms :— “ Law of 8th June 1864, completing, in what relates to gazonnement, the law of 28th July 1860, Sur le Reboisement des Montagnes. “Art. 1. Ground situated in the mountains, the consolidation of which is, by the terms of the law of 28th July 1860, recognised to be necessary on account of the state of the soil, and the dangers which may result to the lower ground, may be, according to the necessities of the public interest, either entirely returfed, or partly returfed and partly rebowséd, or entirely rebovséd. “ Art. 2. Applicable to the work of gazonnement, in so far as they contain nothing contrary to the present /o?, are the Articles 1 to 8, and Articles 11, of the law of 28th July 1860, on reborsement. “Everywhere, with regard to territory comprehended within the péri- métre of obligatory reboisements, previous to the publication of the present law, the Forest Administration is authorised, after consultation with the Municipal Councils of the interested communes, to substitute gazonnement for rebovsement, in such measure as they may judge necessary. “Communes and public institutions, and private proprietors, may call for this substitution. In case of refusal by the Forest Administration, it shall be decreed by the prefect in council, after the fulfilment of the formalities enacted by 3 and 4 of the second paragraph of Art. 5 of the law of 28th July 1860. “The decision of the prefect may be referred to the Minister of Finance, who shall make it law, after having taken the advice of the finance section of the Council of State. “ Art, 3, In every case, communes and public institutions maybe released of repayment to the State by giving up at most the half of the returfed land, during the time necessary to repay to the State, both principal and interest, the advances made for useful works ; or they have the alternative of giving up entirely a part of the land, not to exceed one-fourth, all being specified by professional surveyors. “Art. 4, There shall not be carried on the execution, at one time, of works of gazonnement and enclosure, on more than one-third of the surface to be gazonnéd in each commune, unless the Municipal Council shall authorise them being carried on over a more considerable extent. “ Art. 5, A proprietor expropriated by the execution of the present law has the right of recovering his estate after being gazonnéd, on condition of repaying the price of expropriation, and the expense of the operations, both principal and interest. He can exonerate himself from the repayment for the work executed by resigning one-fourth of his estate. “ Art, 6. An enactment of the public Administration shall determine (1) What measures are to be taken for selecting the portions pointed/out in Art. 1 of the present law ; (2) Rules to be observed for the execution and preservation of the gazonnement ; (3) The mode of determining the grants made by the State, the measures necessary for securing the repayment of principal and interest, and the rules to be followed for the cession or 216 LEGISLATION ON TORRENTS. resignation to the State of the possession and proprietorship of land ; (4) The mode of fixing and allocating grants of money, which, according to cir- cumstances, may be allotted to communes in case of the temporary deprivation of them of pasture on the communal lands which are, for the time being, the subjects of gazonnement or reboisement. “Art. 7. A sum of five millions is set apart to the payment of expenses authorised by the present law, amounting to 500,000 francs per annum. “ This shall be provided by means of extraordinary fellings in the Crown forests being made in aid of the ordinary resources of the treasury.” On the 10th November, in this year, was issued the Imperial Decree, embodying the regulation of the Administration for the execution of the laws of 28th July 1860, and the 8th June 1861, on the reboisement and the gazonnement of the mountains, in which, after the preamble stating what documents had been seen and considered, it is stated,— “We have decreed and decree what follows :— “MipRE I.—REBOISEMENTS ET GAZONNEMENTS FACULTATIFS. “Art. 1. The proprietors of land situated on mountain tops or declivities, who may wish to benefit by the subventions to be granted by the State in terms of Arts. 1 and 2 of the Jaw of 28th July 1860, and of paragraph 1 of Art. 2 of the law of 8th June 1864, should make their desires known to the Conservateur des Foréts. “When a commune or public institution is in question, the request should be made to the prefect, who transmits it to the conservateur, along with his opinion and reasons attached. “ Art, 2, Ground belonging to communes or public institutions on which operations of reborsement or gazonnement are undertaken, with the aid of State subventions, are for the time submitted absolutely, the parts reboiséd to the forest régime, the parts regazonnéd to the pasture regulations pre- scribed by article 21 of the present decree. “These operations, as well as the work necessary for preserving and keeping them up, are effected under the control and superintendence of the forest officials, “ Art. 3. If the ground belongs to several communes, and the success of the reborsements or gazonnements renders necessary combined operation, in accordance with Articles 70, 71, and 72 of the law of 18th July 1837, a Syndical Commission is appointed to attend to and carry on the operation, “Tn any case in which the work has not been done, or has been badly executed, according to attestation of the forest officials, through the com- munes or the public institutions neglecting to conform to the decrees for the regulation of the right of pasturage, the prefect takes out a summons commanding the restitution of the subventions which have been allotted by the State. Art. 4, The money premiums obtained by private individuals are paid after the work is performed, on presentation of a minute declarative of the works having been accepted, prepared by the local forest official in the form of the corresponding minute required on completion of operations for im- proving the crown lands, and on the advice of the inspector of the conser- vateur, “A valuation is made of the subventions of seed or plants which are IMPERIAL DECREE OF 10TH Nov, 1864. 217 given to private proprietors before the beginning of the operations. This valuation is notified to the proprietor, and accepted by him. The amount can be recovered by the State in cases where the work is undone, where there may be an embezzlement of part of the seed or plants, or where the work is badly executed. “ Art, 5, All subventions exceeding 500 francs in value shall be decreed by our Minister of Finance ; all subventions of the value of 500 francs and under shall be granted by the Director of Forests. “Titre II.—Computsory REBOISEMENTS AND GAZONNEMENTS—SETTLE- MENT OF THE PERIMETRES WITHIN WHICH REBOISEMENT AND GAZONNEMENT ARE NECESSARY. “ Art. 6. Whenever the Forest Administration deem it right to fix the périméetre of ground within which reboisement and gazonnement are required, the Director-General of Forests intimates to the prefect the names of the forest officials entrusted with the duty of drawing up the procés verbal of the survey of the grounds, the map of the district, and the plan of the pro- jected operations. “The prefect appoints the engineer of bridges and highways, or of mines, who is to lend assistance. “ Art. 7, The minute of reconnoissance is accompanied by an explanatory memorandum regarding the aim of the undertaking, and ‘the benefits which are to be expected. “The map of the district is prepared with the help of the registrar of lands. The number of the registral volume is given for each portion, also the extent, the proprietor’s name ; and in dealing with a commune or public institution, the total extent of land belonging to the commune or public institution. “The périmétre is marked by a continuous border of a uniform bright colour. The grounds to be regazonnéd or reboiséd are distinguished by flat ‘colours of different hues. “The prospectus of the operations intimates what land is to be reboiséd, and what to be regazonnéd, it also fixes the period within which the whole should be completed, and contains,—(1) An approximate estimate of'the expense, and a rough draft of the division of this expense among the ditferent proprietors ; (2) An indication of the subvention which should be offered to each proprietor; (3) An estimate of the actual value of each parcel, and its value in itself and in its superficies ; (4) When necessary, a note of the indemnity which may be awarded to each commune in cases where there is a temporary deprivation of the pasturing on land included in the périmétre ; (5) And all other necessary statistical information. “ Art. 8. The papers enumerated in the preceding article are forwarded by the Forest Administration to the prefect, who proceeds in each commune to make the enquiries prescribed by Art. 5 of the law of 28th July 1860, and paragraph 1 of Art. 2 of the law of 8th June 1864. «The draft lies at the mayoral office for a month, at the expiry of which time a commissioner, appointed by the prefect, receives at the mayoral office, during three consecutive days, the depositions of the inhabitants as to the public utility of the projected operations. The month specified dates from the time when the project is advertised by proclamation and hand-bills, 2B 218 LEGISLATION ON TORRENTS, “ A certificate from the mayor attests the performance of this formality, as well as the publication of the prefect’s decree requiring the members of the inquest to begin operations. « “ After having closed and signed the register of declarations, the com- missioner transmits it immediately to the prefect, along with his opinion and reasons annexed. He also sends the other papers which have served as a basis to the inquiries. “ Art. 9. The Municipal Council of each of the communes interested, called together by the prefect for the express purpose, shall examine the papers connected with the investigation, and at the end of a month shall give an opinion, by a resolution agreed to by them, along with the super- added assessors, in number equal to that of the acting municipal council- lors. If it is necessary, this resolution shall declare it; if the Municipal Council authorises operations of reboisement to a greater extent than that fixed by Art. 10 of the law of 28th July 1860, also operations of gazonne- ment and of enclosure to a greater extent than that fixed by Art. 4 of the law of 8th June 1864, the minute of this resolution is added to the papers connected with the inquiry. “ Art. 10, The Commission ordained by par. 2 of Art. 5 of the law of 28th July 1860, and par. 1 of the law of 8th. June 1864, is appointed by the prefect in all the departments traversed by the line of operations. “The Commission assembles, in the place pointed out by the prefect, on the fourteenth day after he has given intimation. The papers giving directions are examined, also the declarations handed in to the clerk of the investigation ; and after all necessary information has been collected from persons suitable to be consulted, the Commission gives its opinion, with reasons annexed, both concerning the utility of the enterprise and upon the different questions that have been submitted by Government. “These different proceedings, from which the procés verbal or minute is prepared, should be completed within the course of another month. * Art. 11. The prefect, after having taken advice from the Council of the Arrondissement, and from the General Council, shall forward all the docu- ments, with his own opinion and reasons annexed, to our Minister of Finance, who, after having consulted our Minister of Agriculture, Commerce, and of Public Works, and also, when necessary, our Minister of the Interior, shall lay his report before us. We afterwards, in conjunction with our Council of State, shall decide upon the public utility of the operation. “Art. 12. A duplicate of the decree declaring the public utility of the works is forwarded by the Director-General of Forests to the prefect, who is responsible for the performance of the formalities prescribed by Art. 6 of the law of 28th July 1860, and par. 1 of Art. 2 of the law of 8th June 1864, At the same time the Forest Administration intimates to the prefect, in regard to each registered lot, the operations to be effected, the conditions and time fixed for the completion of the offers of subventions by the State, or the advances they are disposed to give, and finally, if need be, the indemnities awarded for temporary deprivation of pasture. “Tren TI].—Tae Execution anp KEEpina uP OF THE Work. “Cuar. I—Lands belonging to Private Proprietors, included in the Périmétres, fined by decrees declaring their public utility. * Art, 18, At the end of one month, reckoned from the intimation made IMPERIAL DECREE oF 10TH Nov. 1864. 219 to him of the decree declarative of public utility, the proprietor of land included in the périmétre shall declare if he intends doing the work himself, or intends leaving it to the Forest Administration. “Two copies are made of this declaration, and forwarded to the sous- prefecture of the locality, where they are registered. “These copies are examined by the sous-prefect, who returns one to the proprietor, and sends the other immediately to the prefect. ; “Tf the proprietor wishes to do the work himself, his declaration shall contain, moreover, some proof that he has the means of doing so. “ Art. 14. When no declaration has been made within the specified time, it is taken for granted that the proprietor refuses to undertake the work. “ Art. 15. The work completed by a private proprietor, with or without the aid of a subvention, shall be subjected to the surveillance of the Forest Administration. “ Art. 16. The Forest Administration shall proceed to the execution of operations to be effected on expropriated lands. “The completion of the work is notified by the Forest Administration to the expropriated proprietor ; this notification besides contains, (1) a detailed account, principal and interest, of the cost of works executed from the date of expropriation ; (2) an estimate of the annual expense supposed to -be necessary for their preservation and maintenance. « Art. 17. When, in accordance with the Articles 7 of the law of 28th July 1860, and 5 of the law of 8th June 1864, the expropriated proprietor wishes to use his right of obtaining restitution, he makes a declaration to that effect at the sous-prefecture within five years of the notification having been made to him, in terms of the preceding Article. “In this declaration he makes it to be understood whether he wishes to obtain restitution by repaying the money advanced by Government, or by giving up the half of his property if reboisement is in question, or the quarter if gazonnement has been effected. “These declarations are registered and a deed is executed. “ Art. 18. If the proprietor decides on repaying the advances made by the State, he produces in support of his declarations necessary proof to establish that he is in a position to repay the expense of expropriation and the cost of the operations, both the execution and maintenance of them, both principal and interest. “The declaration and attesting proofs are to be addressed, within a month, to our Minister of Finance, who decrees and fixes the formalities and the period within which the proprietor shall have his rights restored. “ Art. 19. If the proprietor offers to resign the half or the quarter of his property, according as the ground has been reboiséd or regazonnéd, a forest official and the proprietor, or his deputy, proceed to the division of the ground—that is to say, if it has been reboiséd, it is divided into two lots of equal value, and if it has been gazonnéd, into two lots, one being three quarters, the other one quarter, of the value of the whole. “Tn case of dispute about the division of the lots, it is made by a third party, an expert, nominated by the President of the Tribunal. ; “Tf one part of the work has been done by the proprietor, he is re- imbursed by a proportionate deduction from the portion falling to the State. ‘Where the land has been reboiséd the division is made by drawing lots when the parties disagree. . 220 LEGISLATION ON TORRENTS. “Cnap. II.—Lands belonging to Communes or Public Institutions tnelucded in the Pérunétres fixed by decree declarative of public utility. “ Sectton Ist.—Execution of works on ground belonging to communes or public establishments. “ Art, 20. Within a month, reckoned from the issuing of the decree declar- ative of the public utility, the communes and public institutions possessing Jand situated within the périmétres inform the prefects, by a resolution, with reasons annexed, if they intend to execute, at their own expense, the whole or part of the work on the conditions prescribed; or leave the State to do it at its own expense, subject to repayment ; or finally, amicably to resign to the State the whole or part of the land included in the périmétre. “When the commune or public institution fail to make known their intention within the above mentioned period, the State undertakes the work in accordance with Art. 8 of the law of 28th July 1860, and of para- graph Ist of Art. 2 of the law of 8th June 1864. “Art. 21. Lands which have been reboiséd, or are to be~ reboiséd, belonging to communes or to public institutions included in the périmétres fixed by the decrees declarative of the public utility of the measure, are subject absolutely to the forest régime. “Ground that has been or is to be gazonnéd, included in the same péri- metres, falls under the application of the provisions and arrangements of the 8th section of Zvtre iii. of the forest code, and the 9th section of Titre ii. of the Act of Ist August 1807, which relate to the arrangements regarding pasture. “ Art, 22, When the commune or public institution has intimated its intention of carrying on the work, the Municipal Council, or the Adminis- trative Committee, annually allots the funds considered needful, either for the execution of new works or for keeping up those already campleted. “ Art, 23. The forest agents superintend the execution of the operations. In cases where the conservatewr has proved that the work has been left undone, or badly done, a decision of our Minister of Finance shall decree that the State shall take charge of the operations, in terms of Art. 8 of the law of 28th July 1860, and paragraph 1 of Art. 2 of the law of 8th June 1864. “When the ground belongs to several communes, and the success of the reboisements, or of the gazonnements, demands combined operations, if all the Municipal Council intimate their consent, a Syndical Commission is appointed to carry on the work in accordance with Art. 70, 71, and 72 of the law of 18th July 1837. “ Section 2nd.—Certification of the sums advanced by Government to the communes and public institutions, and the measures necessary to ensure repayment, “Art. 24, When communes or public institutions intimate that they leave the operations to be performed by Government, the Forest Adminis- tration causes them to be done in accordance with the formalities used when the improvement of the Crown lands is in question. “ The statements of expense are prepared in accordance with the rules of liabilities of the Forest Administration. “Tt is the same with the annual statements of the cost of maintenance. “Art, 25. When several communes are interested in the operations, the IMPERIAL DECREE OF 10TH Nov. 1864. 221 division of expense is made in the way prescribed by Art. 72 of the law of 18th July 1837. “Every year the parties interested receive a statement of the outlay on their behoof made by the State. After the completion of the works, the general account: of the outlay is closed by the Minister of Finance, copies being delivered to the parties interested. The principal, forming the total of the amount, bears simple interest at five per cent. from the date of the completion of the works. “Art. 26. The works effected by the State shall be kept up by the Forest Administration. ““The interest of the advances made by Government for this object, the account of which is closed annually by the Minister of Finance, is also five per cent. per annum. A copy of this account shall be delivered to all parties interested, along with a statement of the expense incurred. - “ Art 27. Appeals for revision or rectification of the yearly accounts of expenses for the completion and keeping up of the operations shall, under pain of forfeiture, be laid before the Prefectorial Councils within six months from the notification of the said accounts. When this time has elapsed the accounts are confirmed. “ Art. 28. A statement of the produce, and one of the expenses incurred, shall be made and closed every year by the Minister of Finance, copies of which are sent to the parties interested. ‘Within six months from this notification, parties interested may, as in the case of the expenses of the works, avail themselves of the privilege mentioned in the preceding Article. “The value of the produce is deducted from the interest due to Govern- ment, and, in subordination to this, from the expense of the completion or keeping up of the works. “ Art. 29. When the advances made by Government are entirely repaid, either by the produce or by payments made by the parties interested, the latter are immediately put in possession of the ground managed for them by Government, under the restrictions resulting from their being subjected to the forest régime as regards the portion reboséd, and with regard to the portion regazonnéd, subject to the regulation repeated in Art. 21 of the present law. “Tf the communes and public institutions wish to repay the sum total of the Government loan, they must prove that they can do so, and execute the necessary commissions. * Section Srd.—Rules to be followed when communes and public institutions give up the enjoyment or proprietorship of grounds, as authorised by Art. 9 of the law of 28th July 1860, and Art. 3 of the law of 8thJune 1864, “ Art. 30. Should a commune or public institution wish to release itself from all Government claims by giving up either the proprietorship cf the half of the ground reboiséd, or the use of not more than the half, or the proprietorship of a quarter at most of lands which have been regazonnéd, the Municipal Council, or the Administrative Commission, shall adopt a resolu- tion relating thereto, with reasons annexed, which resolution shall be notified to the prefect. “ Art, 31. As regards land which has been rebozséd, whien this is to be divided into two portions of equal value, this is done by an expert nominated by the prefect, and a forest agent nominated by the Forest Administration, 929, LEGISLATION ON TORRENTS. “The portions are assigned by lot, when the parties do not agree. This is done before the sous-prefect of the Arrondissement. “Tf a part of the work has been executed by the commune or public institution, this is made up to it in the division by a proportionate deduction from the portion which falls to the Government. “ Art. 32. With regard to ground which has been gazonnéd, the division is made by an expert nominated by the prefect, and an agent appointed by the Forest Administration, according to the valuation of works of public utility effected by the State, and also the settlement of which portions of ground are to be given up to it altogether, or only for a time. “ When there is any dispute, this shall be done by an expert chosen by the President of the Tribunal. “ Art. 33. An account is kept by the Forest Administration of the produce - of ground the use of which has been given up to the State. The enact- ments of section 2nd of chapter ii., T%tre iii, of the present law are appli- cable to this account. “ Section 4th.—Method of determining and allocating indemnities, which may have been granted to communes, when there has been a temporary privation of the right of pasturage on communal land which has been subjected to gazonnement or reboisement. “ Art. 34. In cases where the right of pasturage on communal lands which have been subjected to reboisement or gazonnement has been withdrawn for a time, indemnities are granted in proportion to the resources, to the sacrifices made by the communes, to the wants of the needy inhabitants, and to the sums granted by the General Councils for reboisements and gazonnements. “Regard is also had to any agreement made by any commune to suppress the keeping of goats, either wholly or in part. “ Art. 35, These indemnities are fixed by decrees declaring the public utility of the measure. They date from the day when the right of pasturage ceased, and they are paid into the communal treasury at the end of every year. These appear among the extraordinary receipts, under the name of accidental receipts, and the use to which they are to be put, regulated by the Municipal Council, in the form of sanctioned expenses (dépences Sacultatifs ). “ Cuap. IT],—General Enactments. “ Art. 36. Before beginning operations within the limits of the périmétres fixed by Imperial decree, the limits of the périmétres, and if need be the boundaries of the said périmétres, must be determined at the expense of the State. “ Art. 37. Our decree of 27th April 1861, containing enactments of the Public Administration for the execution of the law of 28th July 1860, on mountain reboisement, is renewed. “ Art, 38. Our Ministers—the Secretaries of State in the department of Finance, in the department of the Intetior, of Agriculture, of Commerce, of Public Works—are intrusted, each in his own sphere, with the execution of the present law. “Given at Compiégne, 10th November 1864.” In 1865 there came into operation the supplemental law in regard to ‘REPORTS OF OPERATIONS, 1865-1866. 223 gazonnement, but circumstances which will afterwards be stated prevented the issue of the official report of operations at the usual time, and the reports for 1865 and 1866 were issued conjointly. From these it appears that in these years nothing was done in gazonne- ments in connection with sanctioned works, or reboisements facultatefs ; but in connection with reboisement and gazonnement obligatoires, 37 new péri- métres, embracing a total area of 25,916 hectares, had been considered, and 31 périmétres, in regard to which the prescribed formalities had been fulfilled, had been decreed of public utility, Works had been cartied on during the same period over an area of 6491 hectares 3 ares, embracing 120 périmétres, of which 41 were new ones. Of these 6491 hectares, almost all had been situated at great elevations, and 1613 hectares 88 ares had been brought under gazonnement. A tabulated statement of all the works executed in 1865 and 1866 is given. And the report goes on to say :— “‘These works were executed at an expense of 924,122°64 francs, of which 55,978°34 francs were subventions, and 16,806°87 francs indemnities anted for. temporary deprivation of pasturage, and the balance— 851,407°43 francs—might be considered money advanced to communes and public bodies which had given up to the Administration the execution of the works, subject to reimbursement, according to one or other of the modes of reimbursement specified by Arts. 8 and 9 of the law of 28th July 1860, and Art. 2 of the law of 8th June 1864. “These indemnities for temporary deprivation of pasturage, provided for by Art. 6 of the law on gazonnement, were—in 1865, 4134°50 francs ; and 12,672°75 francs in 1866.” A tabulated statement, giving details of the expenses met by the State in 1865 and 1866 in these works of reboisement and gazonnement follows, and the report, summarising these, goes on to say :— “The reboisements obligatoires in 1865 and 1866 extended over a total area of 5,919 hectares, of which 1,276-9 hectares have been rebowséd by pro- prietors by aid of subventions, and 4,624°91 hectares by the State in their stead ; gazonnement has been applied during the same time to 2,195-9 hectares; and 91,645 barrages have been constructed within the périmétres, and, in combination with these, numerous lateral hurdles ; the expense of the two operations amounts to the sum total 6f 924,192°64 francs, which has been created thus :— “ Subventions, in kind and in money, allotted for works of reboisement and gazonnement decreed to be of public utility, - Franes, 55,978°34 “ Advances made by the State for reboisement and gazonnement, » 485,219°56 “ Advances by the State for works of maintenance, » 169,641°27 “ Advances by the State for barrages and various works, » 196,546°60 “ Indemnities allowed to communes for temporary de- privation of pasturage, - », 16,806°87 Total, Francs, 924,192°64 “ Besides these works decreed to be of public utility, there were other works sanctioned by the Administration, 224 LEGISLATION ON TORRENTS. “The sanctioned works, travaux facultatifs, of 1865 embraced a total extent of 7,734'15 hectares, and necessitated allocations on the part of the State to communes and private proprietors of subventions, in kind or in money, amounting to 374,772°32 francs, with an expenditure on the works of 169,776°26 francs for the reboisement of lands belonging to the State—in all, 544,548-58 frances. “The subventions, in money and in kind, granted by the Administration for works of maintenance have amounted to a sum of 99,904°10 francs ; the expense of maintenance of State reborsements has been 51,531°75 francs. “ Proprietors of different classes have further constructed, by means of the above-mentioned subventions, 5,804 new barrages, and have repaired 818. “The whole expense to the State for sanctioned works of reboisement, in 1865, has amounted to 695,984'43 francs ; and the expenses of every kind, incurred by communes and private proprietors, for the works for which subventions were granted, including funds granted by the General Councils of the districts, may be estimated at 650,000 francs. . “The extent of land belonging to communes, private proprietors, and to the State, over which reboisement was effected in 1866 was 5,697:80 hectares. The reborsement of lands belonging to the State cost 119,615-77 francs ; the subventions, in money and in kind, granted by the State for reboisements by communes and private proprietors, amounted to 273,484:67 francs ; the maintenance of State reborsements entailed an expenditure of 47,951°85 francs ; the State contributed by subventions, in money and in kind, for the maintenance of reboisement by communes and by private pro- prietors, 112,573-75 francs ; the total expense to the State for sanctioned rebowsement in the course of the year amounted to 553,826:04 francs. “There were constructed in the course of the year in the sanctioned reboisements effected with the subventions mentioned, 2459 new barrages, and besides these, 561 old ones were repaired. The quarter of the expense of the whole work born by private proprietors, by communes, and by departments, was estimated at 400,000 francs.” Tt has been stated, that circumstances prevented the issue of the report for 1865 at the usual time. In reference to this it is stated by the Director-General of the Forest Administration :— “The report, relative to the operations carried on in 1865, could not be produced at the usual time in consequence of serious disturbances which the unexpected inundations in the autumn of 1866 occasioned in the greater part of the mountainous countries the regeneration of which has been entrusted to the Forest Administration. It might be expected that the restocking of forests, executed within a year before, could scarcely fail to have suffered much from such an outbreak of waters, and I thought it desirable, before making known the result of the works, to be fully and correctly informed on the extent of the evil done to them. “Happily,” he goes on to say, “the delay has, and has only, established the fact that any desolations which have occurred are trifling in import- ance compared with the calamities which have befallen the valleys and the -plains. “The deluges of rain which fell on the 23rd and 24th of September in the high lying regions of Auvergne, and of Vivarais, and on some spots in Savoie, transformed the most of the thread-like streamlets almost instan- REPORT ON FLOODS OF 1865-1866. 225. taneously into furious torrents, and raised in less than twenty-four hours, first the Lot, then the Aveyron, the Tarn, the river Arc, the Allier, and the Loire to a height which the greater part of these water-courses had’ never reached, even at the time of the floods of 1856. “Tt may easily be conceived, that in such circumstances the works of reboisement, undertaken within a few years before on the brows and slopes of the mountains, could scarcely have any effect on the enormous masses of water, the impetuosity of which only the oldest woods could be of use in moderating. But if they have opposed no obstacle to the inundations, they have sustained perfectly the shock, and it may be affirmed that they have throughout exercised a happy influence. “Thus in the Lozére, where the bridges carried away or damaged are reckoned by hundreds, where the valleys have been half-filled with sand and rocks, the reboisements and gazonnements executed on about 1700 hectares have perfectly maintained the soil on which they are situated, and protected the lower-lying grounds. “Tn the périmétre of Chadenet, situated above the valley of the Crouzet, of 566 barrages which have been constructed, 2 only have been carried away, and the volume of earth and stones retained by the 564 barrages remaining standing is estimated at no less than 2000 cubic métres, while, on the other hand, all the slopes rendered mobile by cultivation or by excessive depasturage have been cut up into ravines, and yielded up to the water-courses déjections which have increased considerably the disasters experienced. “These results have been established by the prefect of Lozére in a discourse addressed to the Agricultural Society of his department. “In the Cantal corresponding effects have been produced. On the slopes, stripped of woods, there are traces of torrential ravines to.be met with at every step; at the base of these the meadows are covered with gravel and detached rocks ; and the rocks and highways are eut up. But where- ever the temporary prohibition of passage and pasturage has permitted vegetation to develope itself, and on spots on which reborsement has been carried out by the State, by communes, and by private proprietors—reboise- ments which cover a thousand hectares, there is no formation of ravines; and the lands and the lower-lying roads are untouched. “The works executed in the Haute-Loire are much more important than those carried out in the Cantal. Besides the sanctioned rebotsement, re- boisement facultatis, the périmétres, the reboisement of which was decreed of public utility, embraced in 1866 an area of nearly 5000 hectares, on 1650 hectares of which the reboisement has been effected. In the high moun- tains of Mézenc and of Mégal, where most of these périmétres are situated, none of the portions reboiséd or regazonnéd have suffered from the violence of the rains, whilst a contiguous mountain, that of Chaulet, which is being constantly traversed and broken up by the feet of sheep, has been ploughed up into deep ravines. Those good results established in the Mézenc and Mégal are due not to the action of the vegetation drawn over the denuded lands alone, but also to the restraining power of the barrages. Of 407 of these, constructed on the steep slopes of the Holme, nine only have given way before the impetuosity of the torrent of Ponteils. “The department of the Ardéche has scarcely been affected by the storms of rain and the inundations, excepting in the north-west portions, and more particularly in the canton of Saint-Etienne-de-Lugdarés, This 20 226 LEGISLATION ON TORRENTS, canton 1g situated on the plateau, at an elevation of 1200 métres, surmounted by peaks of from 1400 to 1600 métres. In this region is the périmétre of enjoined reboisements, reboisement obligatoire, of Borée, and the unoccupied domains of Mazan and those of Bonnefoi. Scarcely any traces of sand-hills are to be found in the portions which have been reboiséd. But it is not so with the adjacent lands, and more especially with the valley of Saint- Etienne-de-Lugdarés, the basin of the Allier. There, where terminate the slopes which have been sebotséd, the rock has been laid bare, deep excavations have been dug by the waters, and the valley has been covered with the material dug out and carried away. “The department of the Gard, like that of the Ardéche, only suffered in its north-west portion, that is to say, in the Arrondissements of Alais and of the Vigan, in which are situated the principal périmétres of reboisement obliga- toire. With the exception of two barrages carried away by the waters, the works which have been executed have stood wonderfully, and have at the same time protected all the lower-lying lands against erosion. But every- where else, and notably at some distance from the périmétres of Montdardier, of Concoules, of Genolhac, and of Ponteils, new ravines and considerable accumulations of sand have been produced. “In the department of the Puy-de-déme, until 1866, enjoined reboisement had been carried out only in one périmétre, that of Clermont, about 400 hectares of which had been restored at the time of the inundations. But sanctioned reboisements had been there undertaken upon a great scale, and they extended over many thousands of hectares. Both have sustained perfectly the rude test of the deluges of the month of September 1866. In many places they have to some extent contributed to moderate the ravages of the waters. Thus, amongst the affluents of the Allier, the slopes of which have been happily protected by the recent replantings, may be cited the Couze-de-Chambon, ‘This torrential water-course had always, when great rains fell, caused great havoc and desolation in the commune of Chambon d’Issoire. In 1866 the losses sustained, though still consider- able, have been less marked than previously ; moreover, the inhabitants convinced, as_are likewise the agents of the Forest Administration, that the amelioration of the régime of the torrents ought to be attributed to the reboisements effected since 1862, on an area of about 200 hectares, have, without loss of time, hastened to offer contributions of day-labour towards the completion of these useful works. It is befitting to make mention in the same way of the Puy-de-la-Chopine, or of l’Echorchade, the abrupt steeps of which were lately throughout a great extent denuded, and the déjections, spreading far, were augmented by every rain. Sowings and plantations of resinous trees, combined with gazonnement and a system of planting slips or cuttings, which might root, have completely changed the aspect of these grounds ; and the storms of rain of the autumn of 1866, notwithstanding their extreme violence, have not effected any erosion of importance. In fine, in the basin of the Morge, the Arrondisse- ments of Clermont and of Riom, the reboisements of Chatel-Guyons and of Reyot, which are still of but limited extent, have given a striking illustra- tion of the effects which works of this kind may produce. The old ravines are now stopped up, and the little rivers of the Grosliers and the Tiretaine, which in 1835, from the effects of rains like those which have led to the late inundations, would have ravaged and desolated the valleys, have not, it may be said, occasioned any havoc. EEPORT ON FLOODS oF 1865-1866. 927 “Tn the departments of the Loire, the périmétres of which the reboise- ment has been decreed to be of public utility do not as yet embrace more than an extent of 1700 hectares, of which about one-fourth part has been sown or planted. These works are evidently too restricted to be able to exert a really useful action on the neighbouring water-courses, the floods of which are so sudden and so disastrous. But it has been established that they have reduced, in some measure, the rapidity of the flow by the obstacles created, not only by the plants, but also by the dense herbage and bushes which have grown since the grounds were enclosed, or mise en défends. “The numerous barrages erected in the department of Istre have acted well ; they have prevented the crumbling down of the hills—they have slackened the flow of the waters, and arrested on their way the enormous masses of earth and stone which previously would have precipitated them- selves to the bottom of the basin, As for reboisements, properly so-called, they had not been undertaken to any extent previous to 1863. The works are thus of too recent a date to be able to modify the régime of the waters of the district ; but the enclosures, les mises en défends, which have followed as a matter of course the declaration of the public utility of the rebotsements, have had for effect, by covering again vast extents of ground with what may be called a spontaneous vegetation, to arrest the progress of déjections being carried away by the waters. “The suppression, or rather the regulation, of the right of way, and the depasturing of these, has produced an almost immediate effect at Valbonnais, and on the eastern flank of the mountain of Connexe. The creation of ravines, previously so frequent, no longer occurs ; and the old ravines have ceased to be a continuous menace to the population, or to the imperial road from Grenoble to Gap, which used to be cut up whenever a great flood occurred. “The works of reboisement executed in the Maurienne, department of Savoie, extend only over 500 hectares; but old drains, transformed into dangerous ravines, have been stopped, and numerous barrages have been established on spots which were formerly more exposed to erosion. These works have stood well, and everywhere they have prevented the disintegra- tion of the soil. “The departments of the High Alps, and of the Dréme, did not suffer from the rains which caused such great disasters in Central France. Con- sequently, all the works undertaken in these regions by the Forest Administration remain uninjured. “Tn the departments of the Lower Alps, and Vancluse, there have fallen only the usual rains, and there has been no general inundation, “The trifling damages caused by the waters have been only local and accidental. But there may be collected, from the consequences of two days of rain which fell, 2 good many observations which tend to establish the efficacy of the works which have been executed. ‘“‘The ravines which furrow the chantier of the reboisement of Barréme formerly washed on to the imperial road immense quantities of material torn off from the mountain ; now, the slopes are covered with numerous barrages, and there come to the road only small stones mixed with mud, which are easily stopped by the bordering ditch. In the commune of Saint- André, a mass of schistose granite, completely stripped of wood, and in full process of desintegration, has been almost consolidated through the effects 228 LEGISLATION ON TORRENTS. of the Sarrages in combination with plantations, The principal ravine, by which formerly flowed torrents of black mud to the Verdon, which often -spread themselves over the cultivated lands, is now cut up into sections by barrages of stone, and of facines ; the willows, planted in the ground formed by the coming down of earthy material, fixed this mobile soil,—the bottom -bécame level, and the slopes gentle,—and the ravine manifested a tendency to disappear altogether. The influence of barrages was equally shown in the _ chantier of Riou-Chanal, established to reduce the torrent of that name. It has been established that the Riou-Chanal, which formerly brought down locks of from 10 to 15 cubic métres, has been so subdued by the barrages that a foot-bridge, formed of a single plank at the embouchure of the ravine, at the height of a metre, 40 inches from the bottom of it, has not ‘been carried away during many years; formerly, it would have disappeared after the first heavy shower of rain. “The gazonnements being carried out now and for two or three years past in the lower Alps have given very beneficial results. Since the hills bordering the Labouret and the Seyne have been sown with sainfoin, there have no more been seen formed these numerous deep ravines which the waters dig out so easily in the disintegrated schists, of which the moutains in this region are composed. The simple prohibition of pasturing has frequently . produced similar results ; scarcely has the ground been shut up from the flocks than it covered itself again with a vegetation sufficient to extinguish the torrents. This fact has been established on the chantiers of Saint- André and of Castellane, and on many other spots. “Not to multiply citations, which may be considered already too numerous, I shall now confine myself to indicating in a few lines the con- -elusions which naturally flow from the observations collected from all parts of France. “These conclusions may be summed up thus :—The inundations of 1866 had for their point of departure the most elevated summits of the central ' plateau, they were too violent and too sudden to allow of the irruption of the waters into the low-lying valleys being retarded by the works of reboisement erected on only a few isolated spots. “But if the works of recent creation, and the barrages which in com- pleting the effect produced by these do not yet cover areas sufiiciently extensive to cause them to modify perceptibly the régzme of the great water- coures, they have exercised a very appreciable action on the spots subjected more immediately to their influence. ‘“‘They have not only slackened and divided the flow of the waters, but they have, beyond this, retained in their places enormous masses of earth and of rock which these waters would otherwise have swept away with them. “This is one of the most indisputable and most useful of the effects of these works, for it must not be forgotten that the disasters, occasioned by the inundations, are not only those due to the elevation of the bed of the rivers, and to the flowing forth of their waters upon the plains; the desolations committed by them which are most difficult of cure proceed from deposits of pebbles and of sand, and these are the consequences of ravages com- mitted by the waters in the higher-lying regions. “When the rivers come down from wooded regions, which are thus i. protected from being cut up by ravines, their bed is regular and unencum- ' bered with material in transit. If great rains do come, the river may REPORT ON FLOODS oF 1865-1866. 229 overflow its banks, its waters may cover the plains, destroy some crops, and damage dwellings, but all of these damages are easily repaired, if they repair not themselves when the waters recede within their banks. Rivers like the Loire and the Allier, which come from granite mountains which have been for a long time stripped of woods, do not act so. At every flood they sweep away with themselves enormous masses of sand and of pebbles, which they spread over the cultivated fields, thus rendering them for ever unproductive. The bed of these rivers, constantly filling itself up with this debris torn from the mountains which they traverse, is of no depth; and their thalweg, being without any fixity, is displaced at every flood, passing into grounds which speedily disappear, carried away by the current. Now there is no better preservative of rivers against the filling up with sand than the fixation of the soil of the mountains by means of reboisement, or of gazonnement, or of barrages, and works tending to moderate the flow at the origin of the water-courses—that is to say, at the very source of the evil. “The experiment has been made, and now we can forsee from the present that that day is coming when vegetation, drawn again over the slopes of the mountain, shall have consolidated the surface,—when the torrential water-courses shall have been diverted from these, and shall no more carry their déjections to the sea,—when all the old ravines shall have been stopped up, and the valleys and cultivated plains shall have almost nothing to dread from the violence of inundations.” In a subsequent part.of the report, attention is called to the difference between the expense and the extent of the work of reboisement and gazonne- ment in different regions, which is pretty considerable ; and the Director- General of the Forest Admistration goes on to say,—“ These differences result generally from the nature of the works executed. Where the rocks which constitute the soil of the mountains present a sufficiently solid base, and where the water-courses do not charge themselves with great masses of disintegrated material, the operations ought to consist principally in the creation of vast extents of woods, or of dense herbage, destined for the retention of the vegetable earth, to fix it permanently, and as a consequence to control the régime of the waters. Then the artificial works are only accessory, and it sufficed, for the greater part of the time, to bring back again upon the slopes the vegetation which the abuse of pasturage had caused to disappear. But on other gronnd, as in the Alps in particular— where the grounds, devoid of consistency, are constantly being undermined by the waters, and in consequence crumble down on all hands—sowings and plantations would be insufficient to remedy the evil, if the consolidation of the soil were not previously secured by preparatory works, such as barrages, facinages, sustaining walls, and water-leadings from the torrents. “These works, the complete efficacy of which has been demonstrated by six years’ experience, occasion indeed a pretty considerable augmentation of the expense in the reboisement and gazonnement of those périmétres in which they are executed ; but no outlay would appear to be more justifiable, if we take into account the vast extent of lands which are thus protected against the ravages of the waters, a good way beyond the boundary of the périmétres themselves. “Jt would be superfluous work tv go over the different proceedings adopted in the construction of barrages, and other artificial works, in regard to which the necessary details have already been given. I confine myself 230 LEGISLATION ON TORRENTS. to point out the effects which have been produced by these works. A great number of small torrents have been extinguished ; and villages, cultivated fields, and highways, which were severely threatened, have now been placed beyond risk of danger. “‘ Amongst places effectually protected may be named Sainte-Marie, a dependent village of the commune of Vars, in the High Alps, which a previous torrent had repeatedly invaded, and which was in imminent danger of immediate destruction ; that of Chorges, in the same department, which is now traversed by a stream which has become inoffensive ; the Bourg-d’Oisans, in the Istre, the existence of which was imperilled at every storm of rain by the muds brought down by the torrent of Saint-Antoine, the bringing down of which the rebotsement may be said to have entirely suppressed ; and a part of the town of Mende itself, against which the waters of a torrent, now extinguished throughout the whole of its course, were directing their flow. “ The great torrents require more time, and more especially more money to be spent upon them; nevertheless, the effect of the works is already making itself to be felt on many among them, the régime of which has been perceptibly improved; and there are some, even of them, which may be looked upon as extinguished. Amongst others may be mentioned that of Sainte-Marthe, in the High Alps, which was the terror of the valley of Embrun, and which ig now so inoffensive that the inhabitants have in contemplation to bring again under culture all the lands previously abandoned on account of the ravages committed by the waters. “Tn regard to the works of reboisement and gazonnement, strictly so-called, the results established, obtained on the occurrence of the inundations of 1866, admit no longer of any doubt being entertained in regard to the influence which they exercise on the régime of the waters. “The test which these works have just sustained warrant the conclusion that the period of studies and experifnents always needed at the commence- ment of such complicated operations, may be considered as having now come toanend. The forest agents are now satisfied in regard to the best method of procedure, and in regard to the most appropriate kinds of trees to employ. “T shall not attempt to describe the methods which vary, it may be said, ad infinitum, with the regions, the lands, the exposure, the altitude, &e. ; but it may be useful to make known the kinds of trees which have given satisfaction in the different mountain countries of France, and the degree of success which has followed sowings and has followed planting.” There is given a report relative to the different kinds of trees employed, and a tabulated statement of the degree of success which has followed all the operations of planting, of sowing, and of gazonnement, excepting on reboisement facultatifs of less extent than 50 hectares; from the commence- ment of these till 1866 inclusive, the success ranges from 1 per cent. to 100 per cent. The most frequently recurring figures are 60, 70, 75, 80, 85, and 98, and 100 per cent. or complete success is frequently reported. A report of the seeds and plants employed in the works of reboisement and gazonnement follows, stating kinds, quantities, and prices, and the expense of maintaining sécherics, or places for drying seeds, where thege had been erected. This is followed by reports of grounds obtained by expropriation and otherwise, of subventions voted by the General Councils of thirty-six BEPORT FOR 1867-18638. 231 departments, of the Administration and surveillance, and of forest roads constructed or improved under the laws of 2&th July 1860, and of 13th May 1863, from 1861 to 1266 inclusive. In this there are given tabulated statements of 619,7°# métres of new forest roads executed, and of £17,547 métres improved, the former at an expense of 2,209,753 francs, the latter 1,943,966; it shows a similar tabulated statement of 105,781 métres of new roads, anc 10>,760 métres of improvements, commenced in 1866 to be completed in 1867, upon which in 1866 there had been expended respectively 512,509 francs, and 126,932 francs, and a tabulated report of diverse works executed on other than fcrest roads, but also required for the getting out of the product of fellings in the forests, upon which had been expended 151,432 francs. In August 1266 there was issued by the Director-General of the Admin- istration of Forests, a circular, containing instructions and directions in regard to all matters pertaining to the work, arranged under the heads of dunes, reboisement and gazonnement of mountains and sécheries, for the preparation of seeds; (3) roads, bridges, and sustaining walls; (4) house- wells, and cisterns ; (5) saw-mills ; (6) ditches, enclosing-walls, and fences ; (7) works executed for special payments; (8) works executed by forest warders ; (9) works executed by brigadiers, and watchment of deposits; (10) works executed by concessionaries enjoying a temporary concession of advantages; (11) works executed by parties holding concessions of lands ; (12) works executed by holders of concessions of lesser products; (13) works executed by insolvent delinquents ; (14) works executed in repair of disint LANDSLIPS, 245 7 ae ¢ ' _ Neher aoe eye are a ts. at _. On the subject of landslips, there is valuable information supplied by Mr Marsh, in his treatise on The Earth as Modified by Human Action. He says,— Earth, or rather mountain slides, compared to which the catas- trophe that buried the Willey family in New Hampshire was but a pinch of dust, have often occurred in the Swiss, Italian, and French Alps. The commences, is exhibited to the view of the traveller, on the mountain opposite to Lafayette, the Profile or the Old Man of the Mountain, a singular lusus nature, and a remarkable curiosity. It is situated on the brow of the peak or precipice, which rises almost perpendicu- larly from the surface of a small lake, directly in front, to the height (as estimated) of fromy600 to 1000 feet. The front of this precipice is formed of solid rock, but as viewed from the point where the profile is seen, the whole of it appears to be covered with trees and vegetation, except about space enough for a side view of the Old Man’s bust. All the principal features of the human face, as seen in a profile, are formed with suprising exactness, The little lake at the bottom of the precipice is about half-a-mile in length, and is one of the sources of the Pemigewassat river. alf-a-mile to the north of this there is another lake, surrounded with romantic scenery, nearly a mile in length, and more than half-a-mile in breadth. This is one of the sources of the southern branch of the Ammonoosuck, which flows into the Connecticut, These lakes are both situated in the Notch, very near the road, and near to the point where the steep ascent of Mount Lafayette commences. The northern lake is 900 feet above the site of the Franconian iron works, and the highest poiut in the road through the Notch is 1028 feet above the same level. Other curiosities in this vicinity are the Basin and the Pulpit. i “ A portion of the Gap, including the Notch in the White Mountains, which is the most sub- lime and interesting, is about 5 or 6 miles in length. ~It is composed of a double barrier of mountains, rising very abruptly from both sides of the wild roaring river Saco, which fre- queutly washes the feet of both barriers. Sometimes there is not room for a single carriage to pass between the stream and the mountains, and the road is cut into the mountain itself, This double barrier rises on each side to the height of nearly half-a-mile in perpendicular altitude, and is capped here and there by proud castelated turrets, standing high above the continued ridges. ‘Chese are not straight, but are formed into numerous zig-zag turns, which frequently cut off the view and seem to imprison the traveller in the vast gloomy gulf. The sides of the mountains are deeply furrowed and scarred by the tremendous effects of the memorable deluge and avalanches of 1826, No tradition existed of any slide in former times, and such as are now observed to have formerly happened, had been eomapletely veiled by forest growth and shrubs. At length, on the 28th of June, two months before the fatal avalanche, there was one not far from the Willey house, which so far alarmed the family, that they erected an encampment a little distance from their dwelling, intending it as a place of refuge. On the fatal night, it was impenetrably dark and frightfully tempestuous ; the lonely family had retired to rest, in their humble dwelling, six miles from the nearest human creature. The avalanches descended in every part of the gulf, for a distance of two miles ; and a very heavy one began on the mountain top, immediately above the house, and descended in a direct line towards it; the sweeping torrent, a river from the clouds, and a river full of trees, earth, stones, and rocks, rushed to the house aud marvellously divided within six feet of it, and just behind it, and passed on either side, sweeping away the stable and horses, and completely encircling the dwelling, but leaving it untouched. At this time, probably towards midnight, (as the state of the beds and apparel, &c., shewed that they had retired to rest,) the family issued from the house and were swept away by the torrent. ‘Search, for two or three days, was made in vain for the bodies, when they were at length found. ‘They were evidently floated along by the torrent and covered by the drift wood, A pole, with a board nailed across it, like a guide post, now indicates the spot where the bodies were found. Had the family remained in the house they would have been entirely safe. Even the little green in front and east of the house was undisturbed, and a flock of sheep (a part of the possession of the family) remained on this small spot of ground, and were found there the next morning in safety—although the torrent dividing just above the house, and forming a curve on both sides, had swept completely around them, again united below, and covered the meadows and orchard with ruins, which remains there to this day. Nine persons were destroyed by this catastrophe, and the story of their virtues and their fate is often told to the traveller by the scattered population of these mountain valleys, in a style of simple pathos aud minuteness of detail, which has all the interest of truth and incident of romance in its recital, “The number of visitors to the White Mountains has been considerably increased, on account of the interest excited by these avalanches. The most sublime Views of them, (several of which are nearly equal to the memorable one which swept away the unfortunate Willey family), may be seen all along for several miles, in passing through the Notch. They are also observed from various points in the country around, extending down the sides of many of the elevated mountams, and the astonishing effects of this extraordinary inundation are also witnessed in the great enlargement of the channels of the streams which rise in these clusters of mountains, This is,the fact especially with regard to the channel of the principal branch ot the Ammonoosuck, which rises near the summit of Mount Washington,” 246 DEVASTATIONS OCCASIONED BY TORRENTS, landslip which overwhelmed and covered to the depth of seventy feet the town of Plurs, in the valley of the Maira, on the night of the 4th of Sep- tember 1618, sparing not a soul of a population of 2,430 inhabitants, is one of the most memorable of these catastrophes, and the fall of the Rossberg, or Rufiberg, which destroyed the little town of Goldau in Switzerland, and 450 of its people, on the 2nd of September 1860, is almost equally cele- brated. In 1771, according to Wessely, the mountain-peak Piz, near Alleghe in the province of Belluno, slipped into the bed of the Cordevole, a tributary of the Piave, destroying in its fall three hundred and sixty lives. The rubbish filled the valley for a distance of nearly two miles, and, by damming up the waters of the Cordevole, formed a lake about three miles long, and a hundred and fifty feet deep, which still subsists, though reduced to half its original length by the wearing down of its outlet. “The important provincial town of Veleia, near Piacenza, where many interesting antiquities have been discovered within a few years, was buried by a vast landslip, probably about the time of Probus, but no historical record of the event has survived to us. “ On the 14th of February 1855, the hill of Belmonte, a little below the parish of San Stefano in Tuscany, slid into the valley of the Tiber, which consequently flooded the village to the depth of fifty feet, and was finally drained off by atunnel. The mass of debris is stated to have been about 3,500 feet long, 1,000 wide, and not less than 600 high. “ Occurrences of this sort have been so numerous in the Alps and Apen- nines, that almost every Italian mountain commune has its tradition, its record, or its still visible traces of a great landslip within its own limits. The old chroniclers contain frequent notices of such calamities, and Giovanni Villani even records the destruction of fifty houses, and the loss of many lives, by a slide of what seems to have been a spur of the hill of San “Giorgio in the city of Florence, in the year 1284. “Such displacements of earth and rocky strata rise to the magnitude of geological convulsions, but they are of so rare occurrence in countries still covered by the primitive forests, so common where the mountains have been stripped of their native covering, and, in many cases, so easily expli- cable by the drenching of incohesive earth from rain, or the free admission of water between the strata of rocks—both of which a coating of vegetation would have prevented—that we are justified in ascribing them for the most part to the same cause as that to which the destructive effects of mountain torrents are chiefly due—the felling of the woods. “In nearly every case of this sort, the circumstances of which are known —except the rare instances attributable to earthquakes—the immediate cause of the slip has been the imbibition of water in large quantities by bare earth, or its introduction between or beneath solid strata. If water insinuates itself between the strata, it creates a sliding surface, or it may, by its expansion in freezing, separate beds of rock, which had been nearly continuous before, widely enough to allow the gravitation of the super- incumbent mass to overcome the resistance afforded by inequalities of face and by friction; if it find its way beneath hard earth or rock reposing on clay or other bedding of similar properties, it converts the supporting layer into a semi-fluid mud, which opposes no obstacle to the sliding of the strata above. “The upper part of the mountain which buricd Goldau was composed of a hard but brittle conglomerate, called nayel/lue, resting on an unctuous LANDSLIPS AND AVALANOHES, 247 clay, and inclining rapidly towards the village. Much earth remained upon the rock, in irregular masses, but the woods had been felled, and the water had free access to the surface, and to the crevices which sun and frost had already produced in the rock, and, of course, to the slimy stratum beneath. The whole summer of 1806 had been very wet, and an almost incessant deluge of rain had fallen the day preceding the catastrophe, as well as on that of its occurrence. All conditions, then, were favourable to the sliding of the rock, and, in obedience to the laws of gravitation, it precipitated itself into the valley as soon as its adhesion to the earth beneath it was destroyed by the conversion of the latter into a viscous paste. The mass that fell measured between two and a half and three miles in length by one thousand feet in width, and its average thickness is thought to have been about a hundred feet.. The highest portion of the mountain was more than three thousand feet above the village, and the momentum acquired by the rocks and earth in their descent carried huge blocks of stone far up the opposite slope of the Rigi. “The Piz, which fell into the Cordevole, rested on a steeply inclined stra- tum of limestone, with a thin layer of calcareous marl intervening, which, by long exposure to frost and the infiltration of water, had lost its original consistence, and become a loose and slippery mass instead of a cohesive and tenacious bed.” He then goes on to say,—‘In Switzerland and other snowy and mountainous countries, forests render a most important service by pre- venting the formation and fall of destructive avalanches, and in many parts of the Alps exposed to this catastrophe the woods are protected, though too often ineffectually, by law. No forest, indeed, could arrest a large avalanche once in full motion, but the mechanical resistance afforded by the trees prevents their formation, both by obstructing the wind, which gives to the dry snow of the Staub-Lawine, or dust avalanche, its first impulse, and by checking the disposition of moist snow to gather itself into what is called the Rutsch-Lawine, or sliding avalanche. Marschand states that the very first winter after the felling of the trees on the higher part of the declivity between Saanen and Gsteig, where the snow had never been known to slide, an avalanche formed itself in the clearing, thundered down the mountain, and overthrew and carried with it a hitherto un- violated forest to the amount of nearly a million cubic feet of timber. Elisée Reclus informs us, in his remarkable work La Terre, vol. i. p. 212, that a mountain, which rises to the south of the Pyrenean village Ara- guanet in the upper valley of the -Neste, having been partially stripped of its woods, a formidable avalanche rushed down from a plateau above in 1846, and swept off moore than 15,000 pine-trees. The path once opened down the flanks of the mountain, the evil is almost beyond remedy. The snow sometimes carries off the earth from the face of the rock, or, if the soil is left, fresh slides every winter destroy the young plantations, and the restoration of the wood becomes impossible. The track widens with every new avalanche. Dwellings and their occupants are buried in the snow, or swept away by the rushing muss, or by the furious blasts it occasions through the displacement of the air; roads and bridges are destroyed; rivers blocked up, which swell till they overflow the valley above, and then, bursting their snowy barrier, flood the fields below with all the horrors of a winter inundation.” And he adds in a foot-note-—“ The importance of the wood in preventing 248 DEVASTATIONS OGCASIONED BY TORRENTS. avalanches is well illustrated by the fact that, where the forest is wanting, the inhabitants of localities exposed to snow-slides often supply the place of the trees by driving stakes through the snow into the ground, and thus checking its propensity to slip. The woods themselves are sometimes thus protected against avalanches originating on slopes above them, and as a further security, small trees are cut down along the upper line of the forest, and laid against the trunks of the larger trees, transversely to the path of the slide, to serve as a fence or dam to the motion of an incipient avalanche, which may by this means be arrested before it acquires a destructive velocity and force. “In the volume cited in the text, Reclus informs us that ‘the village and the great thermal establishment of Baréges in the Pyrenees were threatened yearly by avalanches which precipitated themselves from a height of 1,200 métres and at an angle of 35 degrees ; so that the inhabi- tants had been obliged to leave large spaces between the different quarters of the town for the free passage of the descending masses. Attempts have been recently made to prevent these avalanches by means similar to those employed by the Swiss mountaineers. They cut terraces three or four yards in width across the mountain slopes, and support these terraces by a row of iron piles. | Wattled fences, with here and there a wall of stone, shelter the young shoots of trees, which grow up by degrees under the protection of these defences. Until natural trees are ready to arrest the snows, these artificial supports take their place and do their duty very well. The only avalanche which swept down the slope in the year 1860, when these works were completed, did not amount to 350 cubic yards, while the masses which fell before this work was undertaken contained from 75,000 to 80,000 cubic yards.’ "—La Terre, vol. i. p. 233. In many cases such as are cited the evil may be traced to the infiltration of water upon argillaceous beds, such as are referred to, which thus become lubricated, and so admit of the sliding over them of thick beds of super- incumbent earth, bearing with them, it may be, houses, and trees, and cul- tivated fields; in other cases, the infiltrated water comes upon beds of raaterials the disintegration of which leads to similar results. ' M. Marschand—after describing a deposit on which is situated the village of Meyronnes, and its lands in the upper part of the valley of Barcelonette, in the Lower Alps, which deposit was then in movement in one mass throughout the whole extent, from Saint-Ours to the Ubayette, a distance of about 34 kilométres, or two miles and a half, threatening direful conse- quences, which he details—states, that any one may see at a glance from a road on the Sylve, a mountain situated on the other side of the valley, that this movement is manifestly attributable primarily to the waters of a stream, the sources of which are, at Fous-Vive and at Saiut-Ours, being absorbed largely by the ground which it traverses, which is thereby soft- ened,—and secondarily to the percolation of water produced by the melting of the accumulated snow on the southern slope of the mountain of Saint- Ours,—and, in fine, to the meadows covering the ground being extensively irrigated, and an additional percolation of water resulting from this irriga- tion. The cohesion of the mass was being thus destroyed, and the base of the mass was being at the same time undermined by the waters of the Ubayette; and it was manifest that the catastrophe threatened must happen sooner or later. PREVENTION OF LANDSLIPS. 249 A similar case is reported by him, as having been seen by him in Tessin, imperilling the village of Campo. In this case the process. was. more advanced than in that at Meyronnes ; the river Rovana, an affluent, of. the Maggia, having attacked the mountain on which the village was standing, In neither of these cases was the ground in movement wooded. But, he mentions also the crumbling of a portion of a forest of Norway firs, 120 métres long by 90 broad, at Giiruigel Bruck, on the mountajn of Giiruigel, on the east slope of which is the source of the torrent Giirbe ; and he states that in the forest of the Giirbe are immense heaps of rubbish, the remains of former landslips, while at a higher level are the denuded mountain sides, whence the material has slid. But it is mentioned by him that above the land bared by the landslips specified, and distant only a few métres from the summit of the mountain, are to be seen numerous springs. And to water thus supplied may be attributed the landslips which have occurred, Such is one of the aspects of the enterprise ; it is to prevent landslips as well as to preserve the lower-lying valleys from déjections. In all such cases as these last cited there is required drainage and desiccation as well as rebowsement and gazonnement. “When the landslips are occasioned by infiltrations of water into ground which retains it in great quantity—as, for example, at Meyronnes, or at the Gtirbe—it is of primary importance,” says M. Marschand, “ to cut off these waters. How this is to be done must be determined by a careful study of the ground, which must be brought, if possible, into a healthy state—(1) By turning off and leading away to a distance from the lands,in movement all the streamlets flowing thither ; (2) Causing all waters, which traverse these lands to follow the line of most rapid declivity ; (3) Searching out the sources which feed the mud, and draining them by carrying off the water by ditches and by tile-drains ; and (4) Suppressing irrigation on, or above the lands in movement.” The work of reboisement—applying that term, as is often done, to the whole of the operation of reforesting the denuded mountains—is thus found to embrace in practice a variety of operations over and above the, mere sowing of seeds and planting of trees. The object aimed at is the. extinc- tion of the torrent, and nothing tending to the accomplishment; of this, is neglected, and there is a pleasurable excitement experienced in observing how this is done. “The extinction of a torrent,” says Cézanne, “ is a struggle with a for- midable foe, in which are called into exercise the same qualifications whigh command success in war,—bravery, energetic perseverance, and that sage tact which discerns the weak point in an enemy and carries the. attack direct to the heart of his defences.” And he cites the torrent of Vachéres as an interesting illustration of the stratagetic skill with which the works employed have been distributed in the basin of the torrent. “The torrent of Vachéres, (says he,) one of the very worst in the Alps, is on the left bank of the Durance, over against Embrun, and in the plain its vast cone of sterile gravel presents a sad contrast to the rich cultivated grounds by which ‘it is bordered, and which by it are menaced. ‘his torrent is in reality a small mountain river, its bassin de réception, cov ering an area of 7000 hectares, or well nigh 3000 acres, embraces excavations in een SENG moot ee . 25, ree 250 DEVASTATIONS OCCASIONED BY TORRENTS, three mountains ; and some of the affluents are 20 and 30 kilombttres, or 14 and 20 miles, in length. In all the upper parts of these, which may be considered the sources of the torrent, the ground is comparatively firm, and the water limpid; but when it approaches the gullet by which it debouches into the plain, it traverses an extensive bed of detritus, apparently a formation of the glacial period, an old morraine it may be, a confused mixture of mud, and sand, and erratic blocks, torn from the far off summits of the High Alps. In this quarter the torrent is enclosed in pre- cipitous banks, to the depth of 100 métres, or nearly 350 feet, and these banks are being eaten away unceasingly at their base, and are in a state of the most complete instability. : “ Here the torrent at once changes its character; clear thus far, here it loads itself with muddy déjections—the everchanging divarications begin— and the least storm of rain causes the hills to crumble down, and gives rise to the most violent effects of a débdcle, or breaking up of adam. Near to this spot the principal torrent receives two considerable affluents: on the right, the torrent of the Grande Combe comes down from the mountain Saint-Sauvier ; while, on the left, the torrent de Homme tears and eats away, in a great fan-shaped basin, the mountain of Baratier. These two torrents wear down a black schistose earth of the worst kind, and, between the two, a single flood suffices partially to dam up the principal torrent, which is then driven against one or other of the confining unstable banks. Thus all the producing causes of disaster meet within a space of about a kilométre, or two-thirds of a mile square ; for this reason those desolate spots have been chosen by M. Costa as the field of battle, while he is satisfied with simply prohibiting the access to flocks in the upper part of the basin. “The bold plan, which is in course of execution, consists in breaking the living force of the principal torrents by a massive wall, behind which the water-course will accumulate its déjectzon in such a way that the base of the existing banks forming the gullet will be covered deep by these ; the crest of these banks will then be broken down, and a gentle and regular slope will replace the torn and ruinous surfaces which they now present. While these works are in course of execution, a longitudinal dike, built higher up the barrages, in a situation happily chosen, prepares for the torrent an arti- ficial bed, into which it will be cast when they shall have banked up the ancient bed. “One of the two affluents mentioned above, de l’Homme, already extinguished by planted banks and small barrages, has become innocuous. And its counterpart, coming in an opposite direction, the torrent of the Grande Combe, which now, after having flowed for some distance parallel to the principal torrent, falls into this below the wear, will, by means of a cutting, the locality for which is indicated by a natural depression in the ground, be brought into the torrent above that barrage. And by the change thus made the torrent of the Grande Combe will be led away to a distance from the black schist, with which it now charges itself to repletion ; the bed which is now hollowing out will be filled, and the hills between which it now flows will be laid out in banks and subjected to the usual treatment. “M. Costa hopes, that by the new channel which he has in view for the torrent of the Grand Combe, the extinction of it will be brought about as by stage effect, for in the course of a few hours the muddy waters of to-day AND PREVENTIVE MEASURES, 251 will have given place to a sheet of limpid water, flowing into the torrent above the barrage.” While all the credit given to M. Costa by M. Cézanne is justly due to him for devising and executing such works, it is also due to M. Surell to mention that the sufficiency of such measures in some cases was not unforeseen by him. In view of the whole subject of torrents, he remarks,— “When a torrent is examined with attention, it may be seen that all its parts are not equally hurtful. The mischief is often committed by but one branch of it, and the others contribute but little thereto. It would, then, be useless to apply the same treatment to all without discrimination ; the attack must be made on the devastating branch, and that once extinguished, the ravages will be found to have ceased.” From what has been stated, it will be seen that the work assumes a variety of forms; but reboisement seems still, as from the first and all along, to be considered the most important, if not the most necessary, of the various forms which the work of extinguishing torrents assumes, or reboise- ment and gazonnement in combination ; and I would now report how the work is being executed in the High Alps, where the importance of this enterprise in all its magnitude has been realised by all classes of the population. There, over the whole surface of the berges vives, sloping but often very steep banks to be covered with vegetation, are traced horizontal level banks, about 6 or 7 feet broad, with a slight inclination towards the moun- tain, designed to give to the water facilities for collecting and remaining there. Towards the edge of these banks, where previously the earth has been loosened to a considerable extent by the pickaxe, they plant broad-leaved trees of three or four years growth in such proximity to each other that the extreme branches touch, and in such a way that the collet of the root is buried some eight inches under the surface of the ground as a security against drought. The stem is pruned to the level of the ground, that too rapid vegetation may not exhaust the plants; and the pruning is repeated until the vigorous appearance of the young trees testifies that their roots have at length reached a moist subsoil capable of supplying them with nourishment. These embankments are made at distances from each other varying with the degree of slope ; and the intermediate strip is sown broadcast with forage plants, or plants chosen from amongst those which grow spontaneously on the mountains. Sometimes, midway between the rows of trees, are planted other hedges of trees which receive less attention, but which grow pretty well in favourable spots; and between these trees, and midway between these rows, there may be planted lines of lucerne, while on the space between grow herbs of various kinds. This is the case where the main lines of trees are from 20 tu 100 feet apart. When the slope is very precipitous, the embankments are sustained by stones or hurdles ; and when on steep declivities the soil is so disintegrated as to be unable to withstand the violent impinging of the rain-drops in a storm, the ground sown is sometimes protected by a covering of straw, or with cuttings of herbs, &c., which the growth of the herbage underneath soon renders unnecessary. ‘ M. Marschand gives the following instructions, and refers to the Traité Elémentaire de Sylviculture of M. Franckausen, translated into French by M, e ! 252 DEVASTATIONS OCCASIONED RY TORRENTS, Amyot, as containing valuable details in regard to the measures adopted—~ both in sowing and planting—in the mountains of the Oberland. Of the preparation of the soil he says,—When the surface of the soil is bare, and of too great a declivity to give any certainty of stability, the first thing to be done is to fix it, which may be done by means of hurdles. The soil being fixed, it is next requisite to prepare it for the reception of seed or plants; and in reference to this he quotes a proverb, current in the south of France, to the effect that good weeding, hoeing, or digging, may count for a watering. And he goes on to remark, that plantations should only be made in ground well broken up and well wrought, any danger of such soil being carried away being met by the hurdles employed. The digging and breaking up, he recommends, should penetrate to a depth of from 16 to 20 inches, and should be accompanied by the removal of stones, and the filling up of the, hollows they created with the good superficial soil surrounding them. When the soil betwen the hurdles has been thus broken up, the location of the plants must be determined by the nature of the soil, On calcareous rubble, the plants must be set immediately below the hurdles, for such ground being constantly falling they will thus be protected from injury by the falling stones. But on ground more stable—as on marls, for example— they may be planted in the middle of the bands between the hurdles, or even immediately above these, the earth which may accumulate from the continuous falling being too little to destroy or injure the plants. When the surface is covered with vegetation, and stable, hurdles are unnecessary ; but it may be well to break up the ground in plots on places so narrow and steep that there may be some danger of the falling down of the earth occasioning erosion. These plots may be from 16 to 40 inches square, or in the some cases the ground may be broken up in horizontal strips 3 feet or more in breadth, and 12 or 15 feet long, at such a distance from each other that the branches of the trees to be planted may touch when they have attained to the state of perches, a distance varying with the kind of trees planted from a fathom to 20 feet. When the work takes this form of strips, it is necessary to make the surface as horizontal as possible ; otherwise, the earth may be swept to the lower edge of it it by the first storm of rain which may occur. In many cases, the lower sides of such strips may be sustained by low walls composed of the stones taken out in breaking up the ground. In stony ground, such walls are built on the upper border of the strips, in such a way as to arrest rolling stones, and so keep these from falling against the plants. This system has been employed with the happiest results by M. Demontzey in the southern Alps, securing at the same time other advan- tages besides that referred to. When it can be done, it is well to leavo the broken-up ground for some time exposed to atmospheric influences—allowing a winter, or at least some months, to intervene between the preparation of the soil and the planting of the trees. With regard to the method of reboisement by sowing seeds of trees, he writes,—“ This method of reboisement it is not in general advisable to adopt, as it rarely gives satisfactory results ; while a considerable gain of time is secured, with greater probability of success, by planting young trees. But _ there is a method of sowing frequently adopted where the ground is pre- pared in strips, which—thanks to the good preparation of the soil, and the relatively pretty large extent of the ground broken up—succeeds well, ; os i AND PREVENTIVE MEASURES, 253 Pa eine way oh, el PEO AEE if “There are made of these a kind of pépiniéres volantes, or temporary nurseries, in the centre and on all points of the lands to be replanted, in which may be found, at befitting times, and at little expense, plants with which to supply void spaces, or even to carry on the reboisement over the entire surface, when a small number of strips may have been sown for this purpose.” Of plantations, he says,—“ The success of these depends on the plants employed, and on the time at which the operation of planting is performed. There has been much discussion on the question, whether this should be done in spring or in autumn. Spring is preferable in the Alps, as the frost of winter extrudes the plants from the ground, and destroys many of them, And there it is necessary to plant as much as possible after rain, while the ground is moist, thus giving the best security for their success ; and where this is made a point of some importance, the pépiniéres volantes are of great service—they allow of young plants being had on the ground at any time ; while the difficulties of procuring plants in sufficient quantity, at a given time, at a great many different places, often prevents their arrival at the time required, and is otherwise prejudicial to the work. ’ “Tt is scarcely necessary,” says he, “to add, that in planting great care must always be taken to place the best soil finely comminuted around the roots, which should be placed and disposed with consideration and attention,—to heap up the soil and press it down with the foot, &c.,—to take, in short, all the care recommended for plantations in general, and which it is unnecessary to repeat.” In regard to the choice of plants, he says,—“ In the Grissons, where the mountains are calcareous, and where the climate in summer is extremely hot, they can use only plants which have been transplanted in a nursery. The plantations always succeed, and the inspector of the forests of the canton, M. Coaz, attributes the success which has been obtained solely to this use of retransplanted plants. “Tn the Oberland, in like manner, they employ only retransplanted plants, and rarely do these perish. There are thus obtained indisputable facts, over against which can only be set the fact of the success of some species of resinous trees particularly robust, such as the Austrian pine and the larch, transplanted or sown; but even these, however, when first trans- planted in the nursery, and then replanted, are unquestionably superior to those which have not been so treated. “The objections which may be raised to the employment of retrans- planted plants, are the pretty high price of them, and the difficulty of pro- curing them in great quantities. But in reply,” says M. Marschand, “‘ to the first of these objections, I have no doubt that the final result will be generally obtained at less expense with retransplanted -plants than with others, taking into account the interminable labour required with these in supplying the places of dead plants—works often more onerous than the original planting. And I can adduce in support of this opinion,” says he, ‘a great many examples of this having been the case in the French Alps. “The second objection may be easily met—it is only requisite to extend the nursery proportionately with the area to be replanted ; if there have been made pépiniéres volantes, in strips within the périmétres, there may be transplanted thence the young plants, and those which are not required may be left there, where they will not fail to grow.” And he goes on to say,—“ It may be superfluous to add, that the superiorty of transplanted 254 DEVASTATIONS OCCASIONED BY TORRENTS, plants over others consists in this, that within one or two years after being transplanted they have acquired body, have become more densely branched, and have formed more tufted and branched roots, and so can better adapt themselves to transplantation to the place destined for their growth. “Plants obtained from the strips where they have been reared are, on the contrary, always rather slender and poor, because they have grown up in a very crowded condition.” The kinds of trees best suited for the work of reboisement is the next subject to which attention is given by M. Marschand. “ The choice of the kind of tree to be planted,” says he, “ought always to be made with great care ; and if it have been practicable to make trial of different kinds in the locality, never should extensive works be attempted with any but the kinds the success of which has been made certain.” And he goes on to say,— “T have seen the most beautiful reboisements obtained by means of—(1) the Scotch fir, (2) the Austrian pine, (3) the Siberian pine, (4) the larch, (5) the Norway fir. “The pin sylvestre (pinus sylvestris), or Scotch fir, transplanted and replanted, succeeds always; it is employed in the Contre-fort of the Alps, which constitutes the principality of Lichtenstein. This tree, which does not grow well but on deep earth, covers in the Alps immense areas, but it becomes remarkable there for its poor and stunted appearance ; and this variety, which offers no redeeming advantage, should be rejected. “The pin noir d’Autriche, or Austrian pine, is very robust, and may be considered the pine of calcareous lands ; it has almost everywhere given very good results; its qualities and its products make it valuable, and it is not without reason that day by day the adoption of it is spreading on all hands. “The pin & crochets, the Mugho or dwarf pine, is common in the Alps; the greatest mass of this in growth which I know extends from the Engadine to the Munster-Thal ; it is the forest of Offen, more than 50 kilométres, or about 35 miles, long. The tree—now creeping on the ground, now shooting up—presents everywhere a poor appearance, and yields wood fit only for fuel. “This tree rarely attains to great dimensions ; it is well, therefore, to be chary in the employment of it—it should be consigned to dolemite chalks, and pebbly ground, unsuitable for all other kinds of forest vegetation. Yet I have often seen this tree in demand in the Alps, though often enough it possessed no claim to be classified with forest trees. “The pin Cembro, or Siberian pine, is a tree growing at great altitudes ; it is not much employed, nor has it generally succeeded well on the Alps. In the Grisons and the Oberland, it is considered one of the most robust of trees, the success of which when planted is most certain. “ The seed of it should be gathered in autumn; during the winter it is kept in sand or in saw-dust, in a place slightly moist and of mild temperature, such as a cellar or stable ; or the cones may be left spread on hurdles in such places. In spring the seeds are slightly watered daily for a fortnight, at the end of which time they are taken out and sown. Unhappily the mice are very fond of this seed, and scarcely have they been committed to the earth when they are devoured ; in Engadine they surround the seed-beds with frames of planks, sunk about 16 inches, and covered with wire-cloth— and thus the mice are kept out. M. Coaz, by successive waterings, causes the seeds to germinate in the boxes in which they are kept during winter, he then sows them on the ground ; and the mice do not attack these, ~ AND PREVENTIVE MEASURES. 255 “The young trees are transplanted when one or two years old, according to their strength, to be planted out two years later, when three or four years of age. “The reboisements executed in the environs of Stalla, below the pass of Juliers, at an altitude of about 1800 métres, or 6000 feet, have succeeded perfectly, not a plant has died; but it may be doubted whether the Siberian pine will have a rapid growth at such altitudes. “The finest masses of this tree which are known to me are situated in the environs of Saint Moritz, Upper Engadine, at an altitude of 1800 métres ; they are very compact and complete, and of various ages, and are beautiful forests. “The meleze, or larch, is the most robust and valuable of the trees of the Alps, and is the one which it should be sought to multiply and diffuse as much as possible. It succeeds pretty often when sown, but always when planted ; and its growth is rapid enough to produce quickly good results, in fixing the soil and regulating the water-flow. “The épicéa, or Norway fir, is not held in high estimation in the Alps. In Switzerland and in Austria it is much employed, even in southern climates ; in general it is planted out after transplantation.” With regard to deciduous or broad-leaved trees, M. Marschand says,— “T am myself no advocate for the employment of these in rebotsements on the Alps. The resinous trees have been located by the Creator on the great mountains, because they possess, in view of the general régime of the waters, properties which the broad-leaved trees do not. “ But I may add,” says he, “that in the level lands of lower-lying spots, extending to 1200 métres, or 4000 feet, in the southern Alps, the acacia succeeds well; the ash and the sycamore equally well; and, in fine, as a bushy growth giving a first shelter, I have seen employed with success the plum tree of Briangon, and the variety of willows which cover calcareous slopes ; on the calcareons coasts of the Adriatic, they employ as a first shelter the juniper. “In conclusion, I repeat,” says he, “that since with care a direct rebotse- ment may be obtained by means of resinous trees, recourse should never be had to provisional protection excepting after the most manifest failure with these.” It may be desired to compare with these matured opinions, deliberately expressed by M. Marschand, the opinions which have been expressed by others. To facilitate this being done I may repeat here that, at the first of the annual conferences of agents employed in the works, instituted by Ministerial appointment, and held in 1861, it was stated that the kinds of trees which up to that time had been employed, had been chiefly the épicéa, or Norway fir, the Scotch fir, the Austrian pine, the Aleppo pine, the Corsican pine, the larch, the ailanthus, the acacia, the Mount Atlas cedar, the white oak, the i/ew, or evergreen oak, the cork tree, the chestnut, the willow, the white poplar, and the birch; and of shrubs—the filbert the shumack, the hazel, &. But this referred to a much wider range of country than the High Alps alone, to which M. Marschand’s remarks refer. The opinions expressed by the agents employed, in regard to the adapta- tion of these several kinds of trees and shrubs for which they had been selected, and in regard to localities for which one and another of them were 256 DEVASTATIONS OCCASIONED BY TORRENTS, Ds sh appropriate, and the annotations of the Administration on the opinions expressed, have been given (ante pp. 177-207). re In the report of operations in 1865-66, it is stated that the kinds of trees most extensively diffused in the region of the Alps—including the Isére, the High Alps, the Lower Alps, and the Dréme—in the order of most importance, were the Austrian pine, the Scotch fir, the Norway fir, the larch, the oak, the Corsican pine, the alder, the ash, the silver fir, and the Mugho, or dwarf pine. And in this region much use has been made of suckers and twigs of willows and poplars and of herbaceous plants. In the Pyrenees—including the Eastern Pyrenees, the. High Pyrenees, the Lower Pyrenees, Aude, and Ariege—the kinds of trees most common were the Scotch fir, the Mugho, the Austrian pine, the larch, the chestnut, the maritime pine, the oak, and the acacia. And in the region of the Cévennes, and the central plateau—including Ardéche, Grand Lozére, Hérault, Puy-de-Déme, Cantal, and High Loire—there were employed principally the Austrian pine, the Scotch fir, the Norway fir, the oak, the maritime pive, the Aleppo pine, and the ailanthus. It is then stated generally that, in the selection of trees, the maple, the acacia, and the filbert, were preferred for uustable ground, on account of their rapid growth and their roots sending forth numerous suckers. The oak and the walnut were reserved for strong, dry, solid grounds ; while in the moist depths of the ravines the alder, the poplar, the ash, the osier, the white willow of the Alps, &c., were made use of. These are, in some soils, preferred to the coniferae, in view of the object aimed at ; and some other trees have been employed experimentally. But a preference or prejudice has been expressed in favour of indigenous trees. Amongst the bushes cultivated may be mentioned the black thorn, the bramble, the myrtle, the juniper, the hippophot, and above all the barberry. This last, by virtue of its strong root, was formerly spread over the country from the valley to the mountain summits, but the root being in demand as a dye, this led to reckless destruction of it, and it had almost entirely disappeared. Amongst the herbs employed are the sainfoin, the lucerne, and the restharrow, a plant indigenous to the combes, which may be seen suspended over the edge of the precipice, the crumbling crust of which it holds and retains as with the grip of despair. In regard to most of the trees, of which mention has been made as used in the work of reboisement, much information may be found in almost any English work on Arboriculture, Forests, or Forest Trees. But when I was engaged in the study of this subject I failed to obtain the kind of informa- tion I required, to enable me to learn for myself, and to give to others, counsel, in regard to measures to be adopted in carrying out works of such magnitude as would be requisite in some of our colonies, if it were attempted to prevent by sylviculture the devastating effects and conse- quences from torrents, and from inundations from which occasionally they suffer. This information is to be had at command in France. In a work entitled ‘‘ Cours élémentaire de culture des Bois créé al’ Ecole Forestiere de Nancy, par M. Lorentz, Directeur-Fondateur de cette école, ancien Admini- strateur des Foréts, Oficier de la Legion dhonneur, Membre Correspondent de la Societe Imperiale d Agriculture, &-., complété et publie par A. Parade, Conseruateur des Foréts, Directeur del? Ecole Imperiale Forestiere. Cinguiéme Edition, publicé par A, Lorents et H. Nanquette, avec une preface par L. AND PREVENTIVE MEASURES, 257 Tassy, 1867,” there is abundance of such information, which I purpose embodying in a separate volume on Forest Science and its practical application in the forest economy of France. Cuap. V.—DEvAsTaTIONS AND RESTORATIONS. There are still extant forests of great extent on the mountains of France, but there have been extensive clearings. And while we picture to ourselves mountains begirt with forests, it is expedient with the object we have in view to introduce into the picture such scenes as have been described in the Introduction, as presented by Devoluy, by the vicinity of Embrun, and by the valley descending from the col Isoard, and others which have been given of the ravages and devastations wrought by the torrents which owe their birth to the clearings which have been made in these ancient forests. Elsewhere it is the same ; and the study of this will show what evils have resulted from what may be considered but partial clearings. M. Cézanne follows up a lengthened lucid and instructive exposition with the statement,—‘“ These long explications which have been given can give but a very inadequate and incomplete idea of the treatment applied to torrents; on the other hand, it suffices to visit any one of the périmétres, and cast a glance over the whole, to receive a convincing demonstration of what is being done, and to be imbued with absolute confidence in the efficacy of the cure. If then the Administration of Forests desires to form at any time a special service for the artificial extinction of torrents, the best measure to take would be to send their agents on a mission into the High Alps, as L’ Ecole des Ponts et Chaussées send their students to visit the works in course of execution.” I am aware of the importance of this suggestion, and I would make the same to those whom I desire to move to the adoption of like measures, Meanwhile, without detriment to this suggestion, I can produce statements innumerable, and of unquestionable authority, descriptive of what was, within the last twenty years, the condition of various localities, and what is the condition into which they had been brought by reboisement and gazonnement, and barrages, at the time when operations were interrupted by war. om students of Forest Science, information embodied in the official documents, of which translations have been given, may suffice to enable them to form a definite idea of what has been done, and enable them, perhaps, by a vivid fancy, to reproduce the past, to picture the present, and to imagine what the future is likely to be ; but others may prefer being supplied with less formal and more detailed information—and such is at command. Sect. L—The High Alps. The state of desolation to which this region had been brought has been again and again brought under notice ; but other details are not awanting, Of that desolation some idea may be formed from the following account of the vicinity of Embrun, given by Surell,—“In going from Gass towards Embrun, following the highway numbered 94, more than a fourth of the journey is made on the beds of torrents, They are seen aa over the G 258 DEVASTATIONS AND RESTORATIONS. whole country, inundating all the valleys, and furrowing all the slopes, and hence comes that air of desolation so peculiar to the country, which at once strikes strangers on their crossing these mountains for the first time. “The multiplicity of torrents in this department is a fearful scourge, it is like a leprosy which has seized upon the soil of the mountains. The torrents eat into the sides of these, and, dejecting on the plains heaps of debris, by a long-continued succession of accumulation they have created enormous beds of déjections which are ever increasing and extending. They threaten to overwhelm everything. They doom to perpetual sterility the soil which they bury beneath their deposits. Every year they are swallowing up some additional estates. They intercept communication between different parts of the district, and hinder the establishment of a good system of roads, And these ravages are to be deplored all the more because they take place in a country which is very poor, and is devoid of manufactures, and one in which arable ground, which is the only resource of the inhabitants, is rare. These, it often happens, succeed in creating a small field, but only after prodigies of labour and perseverance, and then comes the torrent unexpectedly and deprives them, it may be in one hour, of the fruit of ten years of labour and toil. “The dread which these torrents inspire appears in the names which have been given to them. Thus is it with the torrent L Eperoir, the hawk, and with the torrents Malaise, ill at ease, Malfosse, evil pit, and Malcombe, Malpas, Malattret,—all names speaking of evil. Some bear the name of Rabioux, the enraged ; several others that of Bramafaim, howling hunger. There are some which seem ready to swallow up entire villages and even market towns; and there a dark cloud hovering over the sources of the torrent is sufficient to spread alarm over a whole community.” From this statement some idea may be formed of what some thirty years ago was the state of things there. The passage is cited in the official report of works executed in 1867 and 1868, and with it the following statement by M. Surell in regard to what influenced him in doing what he did in the matter is given :— i ‘‘ There was yet another consideration which determined me to undertake this study, and I must say that’ it is this which all along has given direction to mein my work. ‘This wretched department going fast to ruin, and the Administration, whose duty it is to look to the conservation of its territory, not having yet tried to put forth the least effort to avert the coming evil, it appears to be high time to call the attention of the Admini- stration to the state of this country. It seems to be ignorant of the extent of the evil, and it is my belief that in throwing light upon this plague, and showing what might be done to cure it, I am discharging a sacred duty.” “ As may be imagined,” writes M. Faré in the report cited, “a state of things such as this has commanded the most serious attention of the Forest Administration from the time they were intrusted with the execution of the law of 28th July 1860.” Asummary is then given of the extent to which reboisement and gazonne- mnt had been effected, and the Director-General.goes on to say,—‘‘ I have cited above some of the statements made by M. Surell, which bring into prominence the imminence of the danger with which the French Alps were being threatened. In further reference to the sad picture thus presented, and to make apparent the results already produced by the works. of restoration executed by the Forest Administration, I shall confine myself to THE HIGH ALPS,.. 259 reprinting, from a report presented in 1869 to the Conseil Général des Hautes Alpes, by M. Gentil, Ingenieur en chéf des ponts et chaussées, the following passage :—‘ Torrents are one of the most disastrous plagues of the High Alps ; the cones de déjection invade the valleys, bury under their heaps the cultivated ground, end in annihilating every kind of cultivation, and hunt the inhabitants away from the country; and at the same time the erosions occasioned by them destroy the sides of the mountains ; and thus is destroyed at one and the same time all the value of the mountain and the value of the plain, “The embankments attempted on the cones de déjection at the issue of the gorges, by which come down the materials carried off by the waters from the higher-lying lands, have always failed, or at best the effects pro- duced by them have been but precarious. The dikes in a few years have disappeared under the rubbish from the mountain, “*But the Forest Administration has succeeded, by the consolidation of the soil, in the creation of a robust vegetation on the flanks of the bassins de réception. The results are assured : the case of the works at La Batie, at Sainte-Marthe, at Resail, has demonstrated most manifestly and most indisputably, that it is quite possible not only to arrest déjections, but also to re-establish vegetation on mountains the most ravaged by these torrents. “Tt is not required of me here to show by what means the Forest Adminis- tration has succeeded in extinguishing the torrents. I confine myself to specifying the results of these operations. These results, in regard to the valleys, to the lands there, and to the roads by which they are traversed, are remarkable in the extreme, and it is now required of me to point out these to the Departmental Administration. “* From the time that the soil in the bassin de réception is consolidated, and by plantings and sowings and works of the Forest Administration the soil is fixed, material is no longer torn away and thrown into the current which transports it to the lower-lying parts. The waters assume in some measure a regular régime, they come clear and free from mud upon the cones de déjections, they dig out there a stable bed for themselves by carry- ing away the less ponderous material ; at this stage embankment becomes possible in the valley, and it is practicable at little expense to keep in one unchanging direction the flow of waters which no longer carry away the stones. Properties along the banks are then securely protected ; they are no more exposed to a sudden disaster such as those of which we have so many examples ; they recover with this security their money value ; and the population reassured may count upon their harvests. «On the other hand, the fixing of the bed of the current permits the erection of bridges arid aqueducts on the roads and highways; com- munication is protected against the frequent interruptions to which it was exposed when the torrent was in full activity ; and, in fine—nor is this the least important result of the regeneration of the basin of reception—the principal rivers no longer receive the masses of déjection which encumber their beds and create confusion in times of flood. In illustration of these results, which have been thus referred to in a general and summary way, may be cited the following facts:— | “The torrent of Sainte-Marthe, near Embrun, was threatening to extend its déjections, so as to cover the imperial road, No. 94, A proposal to construct a dike on the left bank had been formally discussed ; the expense of this was estimated at about 45,000 francs, and it was considered that it should 260 DEVASTATIONS AND RESTORATIONS, be met in part by the State, and in part by the proprietors on the river bank. But since the execution of the works of reboisement, in the basin of Sainte-Marthe, by the Forest Administration, this water-course has lost its torrential character, and has settled its bed in the cone de déjection, the embankment has become useless, and the project which had been under discussion has been entirely abandoned. “