G.— ENGINEERING. 143 



micro sections of rocks has led to microphotography of metals, which has 

 been of the greatest assistance to the metallurgist in the development 

 and control of those metals which have played such a revolutionary part 

 in modern engineering. Unfortunately, sufficient use is not made by 

 engineers of this powerful aid to uniformity of product. In the work- 

 shops to-day optical methods are used to make true surfaces, and unskilled 

 men use the electric arc and the diffraction grating spectroscope to check 

 rapidly the analyses of bars of various alloys, confusion in which may 

 lead to disastrous results in engines and machines. Accurate pyrometry 

 and uniform distributions of temperature in heating furnaces are essentials 

 of success in many branches of engineering using alloj'-s of steel and 

 aluminium, cold-worked metals and many other forms of materials. Loss 

 and failure are the serious penalties paid for inaccuracy or inability to 

 use these aids. The judgment of the craftsman and the old ' rule of 

 thumb ' methods, which sufficed until comparatively modern times and 

 which, unfortunately, are sometimes practised to-day, are unreliable and 

 lead to serious lack of uniformity in production and not infrequently to 

 failure where success could have been possible. 



Thus it can be said that the important steps that have been made in 

 engineering during the last hundred years and that distinguish this century 

 from all preceding ones were commenced and made possible by funda- 

 mental discoveries of Science, and it can safely be anticipated that no 

 new epoch-making developments in the future will be possible unless 

 preceded by new fundamental scientific discoveries. Sufficient energy 

 can be transmitted across oceans by directed beams to allow of telephonic 

 commxmication. It seems improbable that wireless transmission will be 

 possible for the large outputs of power-generating stations, but what the 

 future is to reveal cannot be known. In any case the fundamental 

 scientific work of Maxwell, Crookes, Hertz, and Fleming was essential 

 before even a start could be made. 



At present we depend upon the natural forces of air and water or 

 the energy of controllable chemical reactions in boilers, engines, and 

 batteries for our sources of power. Visions of engineers controlling sources 

 of atomic energy immeasurably more powerful than those available at 

 present sometimes come to the hopeful, inspired by the developments of 

 experimental and mathematical physics. Rutherford has shattered the 

 nucleus of the atom. Dr. Krapitza, in the Cavendish Laboratory at 

 Cambridge, has claimed to have reached temperatures of 1,000,000° C, 

 and Eddington tells us that in the great power houses of the sun and the 

 stars, where the temperatures are, it is estimated, as high as 40,000,000° C, 

 the energy of the escaping electrons of the atoms is the source which for 

 millions of years has made and will make it possible for the sun and stars 

 to radiate energy without appreciable fall in temperature. 



It may be, and until man is more worthy at least it is hoped that ii, 

 will be, impossible for atomic energy in large quantities to be obtained 

 and controlled. Also it may be equally impossible to obtain energy by 

 the synthetic building up of other elements from the fundamental element 

 hydrogen, which can be obtained in abundance by the electrolysis of sea- 

 water, but whatever the future has to unfold it seems certain that only 

 by following the new ways opened by pure science can there be hope of 



