4 SEPTEMBER 1897, Page 11

THE FUTURE OF WATER-POWER [COMMUNICATED.] T HE closing years of the

nineteenth century—a century which has been so full of change and marked by progress in so many directions—are ushering in a change perhaps more important in its significance for our own country than any that has preceded it, even in this century of progress. This change is foreshadowed by the striking developments of water-power for industrial pur- poses that have been witnessed in both Europe and America during the last six years,—developments which would appear to point to the substitution of water-power for steam-power in industry at some future date, and to the transfer of the chief manufacturing industries from those countries rich in the possession of coal to those rich in the possession of this modern rival of coal,—namely, -water. Ireland was called by one of her poets, "Thou water-full land." The epithet is a good omen for the future. The recent development has been chiefly due to the progress of electrical science ; and the successful application of water-power on a large scale to industrial purposes adds one more to the large number of triumphs with which the electrical engineers of the present age must be credited. Prior to the year 1890 but little had been achieved in this direction, in spite of the fact that the water-wheel was one of the oldest means for the production of power, and that the mathematical principles of the turbine were fully worked out by Eytelwein and Fourneyron in the early years of the present century. The water-wheels which existed in our own and other countries were mostly small in size, and were only used for the development of power for un- important or local industries. An interesting example of the old method of utilising water-power for industries may be seen at Zurich. The old bridge over the Limmat still has a number of water-wheels in its arches, and directly above these, on the bridge itself, are the shops in which the small industries are carried on which use the power thus generated. In our own country there are still a considerable number of these old water-wheels in existence, and these, with the old mill-buildings, often form a most picturesque incident in the landscape. But after the invention of the steam-engine, engineers paid little attention to this older method of developing power, and no advance in the industrial application of water- power occurred during the second and third quarters of the present century. This arrest of progress was chiefly due to the growth of the scale of manufacturing opera- tions. In the earlier days, the power required to drive a mill rarely exceeded 100 horse-power, and there were a very large number of mills in existence, the power requirements of which were only one-third of this amount. As the modern factory system gradually developed, the power required for driving a single mill increased from 50. up to 1,000 horse-power, and the development of this large amount of power by means of the old form of over-shot or under-shot water-wheels was practically impossible. A further cause for this arrest of progress lay in the necessity imposed upon the manufacturer by the extended scale of his operations and by the keenness of the competition to which he was subjected, for placing the mill or factory as near as possible to the markets for the raw materials and the finished goods. The economy in the expenditure upon power which might be effected by erect- ing the factory in the heart of some country district where cheap water-power existed, was found to be more than counterbalanced by the increased expenditure upon car- riage and freight that this position would entail ; and on this account more attention was paid to the position of the factory with regard to railway and water communication, than with regard to its proximity to a cheap supply of power. These two hindrances to progress have now been overcome. The water-wheel has been replaced by the turbine, which can be adapted to any head of water, and by means of which water-powers of the greatest magnitude may be successfully developed for industrial purposes. The head of water under which the old mill-wheels were worked rarely exceeded 20 ft., and was generally much below that limit ; to-day heads of water of 140 ft. and 210 ft. are being used at the two power-plants at Niagara Falls ; and at Fresno, in California, there is a water-power plant working under a head of 1,400 ft. ! When it is remembered that the height or head of water is one of the factors which determine the amount of energy developed, the significance of these figures is apparent. As regards the amount of power developed—it has already been mentioned that under the old system 100 horse-power might be regarded as a maximum — to-day there are at Niagara single turbines which produce 5,000 horse-power, and there is uo proof that even these enormous wheels represent the limit in size which may not be safely exceeded. But even more important than the results which have resulted from the sub- stitution of the turbine for the older water-wheel are those which have been produced by the introduction of electric transmission. In the older system the machinery in the mill had to be coupled directly to the water-wheel by shafting and gearing, and hence these old mills were necessarily built upon the banks of the rivers and streams whieh pro- vided them with power. In the modern system of trans- mission by alternating electric currents, the mechanical energy developed by the turbine is converted on the spot into electrical energy by means of the dynamo ; and this electrical energy is then carried by air-lines to the locality where it is to be used. There is a certain amount of loss suffered in this operation, a loss that increases with the distance to which the power is transmitted, and it is still most economical to use the electrical energy on the spot ; but the electrical energy derived from water-power is in many places so low in cost that it can be delivered—notwithstanding the loss incurred by transmission—at distances ranging from ten to one hundred miles, more cheaply than it could be produced by steam-power at the place of utilisation. Thus the modern factory or mill driven by water-power need not necessarily be situated in mountain-locked valleys miles from the nearest railway and remote from the industrial centres of the district. It may be built wherever the natural and economic conditions are most favourable to the manufacture, aud the electrical energy, (level ped miles away can be delivered at the factory by an air-cable as easily as water may be delivered through pipes from a distant reservoir in the hills. The greatest activity in the application of these modern methods for the utilisation of water-power is now being displayed in both Europe and America, and the following figures, which represent the aggregate horse-power already developed, or in course of development, will give some idea of the wonderfully rapid advance that has occurred in recent years in this branch of engineering science. In America the total of the larger installations is 72,000 horse-power, with the prospect of this total being increased to 150,000 when the Niagara scheme is com- pleted. In addition to this, there are a very large number of smaller plants in operation in the mining districts of Colorado and Nevada. Switzerland occupies the second place with 32,000 horse-power. This will be increased to 48,000 when the second water-power plant on the Rhone, near Geneva, is completed. France follows with 18,000 horse-power, which will be increased to 30,000 by the completion of the power-plant near Lyons. Germany has only one water-power of any magnitude, that at Rhein- felden. This will yield 16,000 horse-power when com- pleted. Italy has 18,000 horse-power ; Sweden and Norway between 10,000 and 20,000 horse-power each, with almost limitless possibilities of further develop- ment; while England and Scotland come at the end of the list with only 4,000 horse-power.

The purposes for which this power is being utilised are exceedingly varied. It is used directly as electrical energy for lighting purposes, and for chemical and metallurgical operations. Transformed again into mechanical energy by means of the electric motor, it is used for working tramway systems, for producing wood-pulp for paper- making, and for driving machinery of all kinds at the mines or in engineering and other workshops. The significance of this new step forwards in the application of water-power to industrial purposes is startling. On the one hand, it signifies that man has at last learned how to effectually master and utilise one of the mightiest natural forces of the earth. Coal is an exhaustible possession, and the day must come when the coalfields of the earth will be worked out. Our rivers and falls offer, on the other hand, an inexhaustible supply of energy ; for so long as the heat of the sun evaporates the water of the sea, and causes it to fall again as rain upon the hills, or as snow upon the mountains, this source will be available for the supply of man's wants, and the arrival of the time when the earth's coalfields will be exhausted need no longer be awaited with misgivings. But there is another aspect of this development which is less cheerful for contemplation by three of the nations of Europe. The position which England, Germany, and Belgium occupy to-day as the leading manufacturing countries of Europe has resulted chiefly from their possession of extensive coalfields capable of cheap development, coal having been in the past the chief factor in determining the industrial progress of any country. The progress of electrical science has, however, apparently changed the conditions of industrial supremacy ; and it appears as though the possession, not of coalfields, but of water-power, will be the determining factor in the future. Whether the check to the natural growth and expansion of industry in the older manufacturing coun- tries of Europe, that may already be observed as one result of the increased use of water-power in countries hitherto of little or no account in the industrial struggle, will be followed by the gradual migration of the staple industries to the cheaper centres of power, remains for the future to disclose ; but it is a question of tremendous significance for the prosperity of the countries concerned. It would involve a rearrangement of the relative position of the nations of Europe, and however pleasant the period of transition and change might be for the nations which would thereby rise into industrial importance, it would most certainly be very much the reverse for the peoples of those three countries of Europe which to-day stand fore- most in the extent and number of their manufacturing industries.