A WEEKLY ILLUSTRATED JOURNAL OF SCIENCE. 



" To the solid ground 

 Of Nature trusts the mind which builds for aye." — Wordsworth. 



THURSDAY. MAY 



1908. 



LA HOUILLE BLANCHE. 



Service d'Etudcs dcs grandes Forces Jiydrauliques 

 (Region des Alpes), Antiales de la Direction de 

 I'HydraiiUqiie. In two volumes. Vol. i., pp. 181; 

 vol. ii., pp. 451; with maps and diagrams. (Paris: 

 Imprimerie nationale.) 



MOUNTAINOUS countries are ill adapted for con- 

 venience in travel and transport, but as some 

 compensation for this drawbaclc, Nature has endowed 

 them with a signal benefit of another and equally 

 important kind. She has placed at the disposal of the 

 inhabitants a form of energy which is not only readily 

 utilisable, but in the majority of instances is cheap and 

 plentiful, and, it may be added, is also picturesque. 

 The numerous streams of water which streak the 

 mountain sides like veins of silver ore, or which 



" like a downward smoke, 

 Slow dropping veils of thinnest lawn," 



spread themselves over the ledges of precipitous cliffs, 

 possess a wonderful commercial value. They are, in- 

 deed, to be reckoned among the most utilitarian assets 

 and resources of a country, side by side with coal, 

 iron, and other such serviceable minerals, while they 

 possess the additional advantage that their application 

 to industrial purposes is readily effected, and is almost 

 as unlimited in scope as the supply is, apparently, 

 inexhaustible. The French have poetically referred to 

 thc' latent wealth of these mountain streams as la 

 houille blanche (white coal), and coal they surely are, 

 to all intents and purposes, for when diverted into 

 proper channels, do they not serve to actuate wheels 

 and vanes, motors and turbines, setting in useful 

 motion a wide range of plant and machinery as effec- 

 tively as coal itself, without the complicated series of 

 transformations required before the latter is converted 

 into horse-power units? 



The study, then, of so valuable a source of indus- 

 trial energy is almost an obvious duty on the part of 

 (he countries thus enriched. Not until within the last 

 fifteen or twenty years, however, has this duty become 

 NO. 2010, VOL. 78] 



definitely recognised as a national obligation deserv- 

 ing of governmental support. At the present time in 

 France, Switzerland, and Italy, three countries enclos- 

 ing or bordered by lofty mountain ranges, there are 

 organised commissions, subsidised by their respective 

 Governments, for the purpose of collecting data and 

 establishing records of the various changes in flow and 

 level of mountain streams. 



In Italy the initiation of systematic hydrographical 

 research dates from 1890, when Zoppi was commis- 

 sioned to study successively the ."Vniene, the Nera, the 

 Velino, and their principal affluents. The Swiss hydro- 

 graphical service was inaugurated by a federal decree 

 of 1895. France did not recognise her obligation until 

 eight years later, and the first of the two volumes 

 under consideration opens with an account of how an 

 instruction of the Minister of Agriculture, dated March 

 25, 1903, set upon a proper footing the study of ques- 

 tions affecting the assessment of hydraulic power in 

 mountainous regions and the utilisation of the energy 

 therein contained by the regulation of channels or of 

 the water itself. 



The hydrological service thus established was first 

 allocated to the Alps, to be extended later to the 

 Pyrenees, and ultimately, if it be considered desirable, 

 to the whole country. Its programme comprises, first. 

 the purely physical investigation of watercourses and 

 their basins from a geographical, meteorological, and 

 hydrographical point of view; and, secondly, the- eco- 

 nomical study of questions involved in the utilisation 

 of the energy produced. 



The first part of vol. i.'is devoted to an account of 

 the steps taken and the results achieved during the 

 first year, or rather during the whole period prior to 

 1904. There is some reference to early attempts at 

 gauging the Isere and the Durance, and a deduction, 

 from these and similar experiences, of methods advis- 

 able to be pursued in the future. • 



Then follows a detailed account of the observations 

 made and recorded during the years 1904 and 1905. 

 Both this and the preceding section are arranged on 

 common lines, and the subject is treated under several 

 heads, comprising : — 



(i) General organisation and programme of work. 



B 



