MECHANICAL ENGINEERING. 147 



confirmed 'Law of Substance,' as Haeckel denominates it, the principle 

 in nature which I enunciated a quarter of a century ago thus: 



"All that exists, whether matter or force, or their product, energy, 

 and in whatever form, is indestructible except by the infinite power 

 which has created it."* 



This principle, probably as old as Aristotle, or older, enunciated by 

 Cicero when he declared, " One eternal and immutable law embraces 

 all things and all times;" experimentally proved, at least qualitatively, 

 by Kumford in the latter part of the eighteenth century, confirmed by 

 Davy, proved and quantitatively illustrated by Mayer, by Joule and by 

 Eowland and numerous contemporary investigators, the Law of Sub- 

 stance of Haeckel, is itself a nineteenth century product and the basis 

 of our whole system of energy production, transmutation and trans- 

 mission, the foundation of the whole superstructure in mechanical en- 

 gineering and of its wealth-production, and of human progress and 

 higher human life. 



Education in applied science and in the principles directly under- 

 lying the work of the engineer, in common schools, secondary schools 

 and professional schools and colleges, an education which has seen as 

 much improvement as have the arts and sciences themselves, has had 

 much to do with the later progress of mechanical engineering, especially 

 in the United States. Systematic instruction in the departments of me- 

 chanical engineering, such as is now obtainable by almost any young 

 man determined to secure it, not only has much to do with our progress 

 at the moment, but it is this phase of education, in our state colleges 

 particularly, which is settling the tendency of the flow of the rising 

 tide for the immediate future, and probably for all coming time. Al- 

 though it has been a force of recognized importance and influence for 

 less than a single generation, and has had a distinct and special position 

 among 'the educations' for a very brief period, it has already done much 

 to correct the defects of the industrial system of our country — still 

 more that of France and that of Germany, hardly less that of Great 

 Britain — and also to systematize our industries. The discoveries of 

 science and the inventions of our mechanics ""furnish material to be 

 utilized by the alumni of our technical and professional schools and 

 colleges as they can be by no other class in the community; the scien- 

 tific method of the schools and the scientific knowledge of their gradu- 

 ates, and the hands and brains of the new leaders of the industrial 

 army give perfected organization and improved administration to every 

 branch of the great economical, machine-like, modern industrial sys- 



* Proceedings of Am. Assoc, for Advancement of Science, 1878; Vice-Presiden- 

 tial Address: 'The Scientific Method of Advancement of Science.' — R. H. T. 



Also 'Manual of the Steam-Engine,' Vol. 1, Chap. IV, §75, p. 299, The 

 Popular Science Monthly, March, 1901. 



