90 



SCIENCE. 



[N. S. Vol. XIV. No. 342. 



times not. But, whatever the result, he 

 has added to his knowledge of the laws of 

 combinations and has furnished to the phi- 

 losopher fresh data for his generalizations, 

 and to the engineer a new material for his 

 use. 



It not infrequently occurs that, from in- 

 vestigations made for a specific purpose, 

 results are obtained of the greatest useful- 

 ness for an entirely different purpose. 

 Thus, in 1855, when Henry Bessemer, in- 

 spired solely by that desire ' to kill some- 

 thing ' which is alike the ruling passion of 

 the rudest savage and the most highly 

 civilized man, bent all his energies to the 

 production of a metallic combination which 

 should be able to resist the force of the 

 highest explosive and so enable a cannon 

 ball to be projected from a gun to a greater 

 distance than ever before, he discovered a 

 method of expelling all foreign substances 

 from iron and then adding a minute quan- 

 tity of another element, carbon, in such pro- 

 portions that the original mass was mate- 

 rially changed in character and made more 

 ductile, stronger and stiffer. The product 

 was exactly what the railroad engineer 

 wanted at that time for the bearing surface 

 of his roadway, and the material which had 

 been sought for destructive purposes be- 

 came a most important factor in facilitating 

 the transportation of men and goods with 

 certainty and safety at high speeds. 



As the knowledge of the nature of steel 

 and the precise methods in which it can be 

 manufactured have progressed, the engineer 

 has gradually come to know just what he 

 wants and how it can be produced, and, in 

 his specifications, requires that the particu- 

 lar material of this class which he desires 

 shall be of a certain chemical composition 

 and also possess certain characteristics. 

 The same is the case with almost every 

 material which enters into the construction 

 of engineering works of the present day. 

 Matter in its original state is rarely used. 



Its chemical condition must be transformed 

 before the engineer can utilize it with any 

 confidence. That almost any desired trans- 

 formation can be effected was not realized 

 until late in the century. Starting with 

 the atom, the ultimate particle of matter so 

 far comprehended by us, the chemist found 

 that several different kinds of atoms could 

 be identified, and that these would combine 

 in certain ways according to laws which 

 could be formulated. But in the applica- 

 tion of these laws and the tabulation of the 

 results gaps were found to exist which 

 could not be filled without the supposition 

 that other elements existed than those al- 

 ready known. The existence of such ele- 

 mental substances was confirmed by the 

 revelations of the spectrum analysis, and, 

 later on, several of such elements have 

 been actually identified by the use of the 

 electric current in creating vibrations in the 

 ether. The limit is probably not reached 

 yet, but as each new element is discovered 

 its aflBnities are sought by the chemist, its 

 sensibility to various forms of vibratory 

 motion are investigated by the dynamist, 

 as we may term the physicist who is seek- 

 ing the laws of either heat or light or elec- 

 tricity, and then it is the function of the 

 civil engineer to study how it can best be 

 applied to the use and convenience of man. 

 For, ever since the beginning of the nine- 

 teenth century, the evidence has been cumu- 

 lative that matter in motion accounts for 

 all physical phenomena, that motion pro- 

 duces energy, that energy is never wasted, 

 but is simply transformed, and that it mani- 

 fests itself to the senses of man in various 

 modes which are appreciable by the several 

 organs of sense. • 



What our senses recognize as chemical 

 affinity, heat, light and electricity, are sim- 

 ply conditions of matter induced by vibra- 

 tions or quivers or waves or strains, what- 

 ever we may call them, of different kinds 

 and at different velocities. Neither matter 



