February 14, 1918] 



NATURE 



477 



parts of the world where such systems are in existence, 

 notably in Chicago (Illinois), on the north-east coast ot 

 l~ngland, on the Rand, and in certain industrial dis- 

 tricts of Germany. Power production in large super- 

 plants, with generating machines of 50,000 h.p. or 

 more, will not only be far more economical than in a 

 large number of smaller plants, but will also ultimately 

 involve great economies of capital by securing a better 

 load and a more effective use of the plant. Such 

 super-plants, if suitably situated on large sites, would 

 make it possible — so far as it was economical to do so 

 —to extract the by-products in the shape of oils, motor 

 spirit, etc., from the coal before using it as fuel, thus 

 avoiding to a large extent the necessity of importing 

 them. 



(7) The super-plants would feed into the main trunk 

 distribution system, which must be laid down throughout 

 the country. For this purpose the country should be 

 divided into some sixteen districts, throughout each of 

 which there should be a standard periodicity and main 

 trunk voltage. 



(8) This main trunk distribution system would col- 

 lect any waste power available wherever situated and 

 deliver it where it could be profitably used. It would 

 also, by saving the cost of transport, make it com- 

 mercially possible to bring- to the surface much coal 

 at present wasted and left in the pit which, under 

 the new conditions, would be turned into electrical 

 energy at or near the pit-head. 



(9) If power supply in the United Kingdom were 

 dealt with on comprehensive lines and advantage taken 

 of the most modern engineering development, the 

 saving in coal throughout the country would, in the 

 near future, amount to 55,000,000 tons per annum pn 

 the present output of manufactured products. 



(10) If the coal so saved were used for the produc- 

 tion of further power it would be possible to generate 

 continuously not fewer than 15,000,000 horse-power, 

 which would more than compensate for the absence of 

 large watef powers in this country and admit of the 

 manufacture here of many products which are at pre- 

 sent made only in America and on the Continent. 



(11) The development of such a power svstem may 

 be likened to the development of the railways of a 

 country, and it is just as impossible to secure econom- 

 ical power generation and supply by each municipal 

 area working independently, which is the position 

 to-day, as it would be to have an efficient railway 

 system if each municipal area owned its own lines, 

 and long^-distance transport were provided for by 

 running-power agreements. History shows that in the 

 early stages of railway development in this country 

 exactly the same process of amalgamation had to be 

 gone through. 



(12) The present system of electrical power distribu- 

 tion throughout the country, which is undertaken by 

 more than 600 authorities in as many separate dis- 

 tricts, is technically wrong and commercially un- 

 economical. The present average size of a generating 

 station is only 5000 horse-power, or about one-fourth 

 of what should now be the smallest generating machine 

 in the power station. The " Power Act " legislation 

 inaugurated some fifteen years ago has not had the 

 desired result on account of the restrictions imposed 

 upon the power companies. 



(13) .A national system of electric power supply w-ould 

 greatlv facilitate the electrification of railways with its 

 attendant advantages, save large sums of money at 

 present spent on the transport and distribution of coal, 

 and bring within reach of the community as a whole 

 the great benefits of an increase in the use of electricity 

 for domestic purposes, advantages which, taken to- 

 gether, are perhaps of more value than the direct coal- 

 saving. 



NO. 2520, VOL. 100] 



PHYSICAL SCIENCE AND THE ART OF 



EXPERIMENT.^ 

 'T" HE exigencies of the war had seriously impeded the 

 * work of the Physical Society, as of all our scien- 

 tific institutions. Many members were at the front; 

 many others were busy on war work, and there was 

 little time available for normal scientific pursuits. 

 Since his predecessor's address, the scientific com- 

 munity had been stirred to an extent which he thought 

 was unnecessary by the passing of the Daylight Savmg 

 Act. Scientifically the thing was a sham, and as sucti 

 was naturally distasteful to us ; but the community at 

 large was not scientific, and had a very vague notion 

 of the meaning of time. In the stress of war people 

 had realised the desirability of starting the day earlier 

 to save, not daylight, but paraffin and gas, and the 

 simple operation of putting all the clocks wrong, though 

 hateful in principle, did not disturb the public at all. 



In reference to the question of the metric system, 

 this was important in relation to education. The 

 reason why English schools were so backward in mathe- 

 matics was that so much of the available time had to 

 be devoted to memorising tables of weights and measures 

 and similar medieval relics. 



Another matter of public importance was the recog- 

 nition of science as an element of general education. 

 It is sometimes urged that our officials need not be 

 scientific, because they can get all the scientific advice 

 they want. But they may not know when they require 

 it, or appreciate the force of it when they get it. He 

 might instance in this connection the wasteful method 

 of street darkening which still prevails after three 

 years. The annual trouble with frozen water pipes was 

 another example of the general ignorance of scientific 

 principles. Burst pipes were unknown in really cold 

 countries, where the elements of common sense were 

 allowed to prevail. 



All his own contributions to physical science had 

 been experimental, and some words on the art of ex- 

 periment might not be out of place. In order to suc- 

 ceed as an experimentalist it was necessary to find by 

 personal experience how as many materials as possible 

 behave under as many conditions as possible, and this 

 can only be done by one who will practise every art 

 and use every tool and instrument that he can. While 

 endeavouring at first to imitate the practices of the 

 professional mechanic and acquire as much of his skill 

 as possible, the experimentalist must not be bound by 

 tradition and custom in his methods. It is the slavery, 

 to tradition and practice that makes the assistance of 

 the professional so tiresome to the experimentalist. In 

 this connection a saying of Fresnel had greatly im- 

 pressed him—" If you cannot saw with a file and file 

 with a saw you will be no use as an experimentalist," or 

 words to that effect. He had made it his business to 

 use every tool and to handle every material that he 

 could. On one occasion he had had the somewhat rare 

 opportunity of handling five or six large uncut dia- 

 monds, each as big as a walnut. Glass-blowers are 

 familiar with the difference in the contact of freshly 

 blown bulbs and of bulbs some time blown ; but the 

 contact of diamonds was unlike either. When brought 

 lightly into contact they emit a curious squeaking note 

 of possibly 2000 vibrations per second. This meant 

 that the diamonds were bouncing with slowly diminish- 

 ing excursions of 1/80,000 of an inch approximately, a 

 phenomenon only possible with a material of such per- 

 fect elasticity or hardness. It was possible that a test 

 of this kind might be useful for discriminating between 

 the hardness of the harder materials. The whole ques- 

 tion of what hardness was, and if, indeed, it were really 



1 Abstract of the pr- s-dential address delivered to the Physical Society 

 January 2; by Prof. C. V. Bojs, F.R.S. 



