Of course the very purpose of these lists--namely, to compare the achievements of one century with those of other centuries--inclines us to view each invention as an isolated phenomenon, disregarding its antecedents and its relation to contemporary inventions. Studied in its development, steam navigation is but an application of one kind of steam engine, and, moreover, must be viewed as a phase in the evolution of navigation since the earliest times. Like considerations would apply to railways, antiseptic surgery, or friction matches. The nineteenth-century inventor of the friction match was certainly no more ingenious (considering the means that chemistry had put at his disposal) than many of the savages who contributed by their intelligence to methods of producing, maintaining, and using fire. In fact, as we approach the consideration of prehistoric times it becomes difficult to distinguish inventions from the slow results of development--in metallurgy, tool-making, building, pottery, war-gear, weaving, cooking, the domestication of animals, the selection and cultivation of plants. Moreover, it is scarcely in the category of invention that the acquisition of alphabetic writing or the use of Arabic numerals properly belongs.
These and other objections, such as the omission of explosives, firearms, paper, will readily occur to the reader. Nevertheless, these lists, placed side by side with the record of theoretic discoveries, encourage the belief that, more and more, sound theory is productive of useful inventions, and that henceforth it must fall to scientific endeavor rather than to lucky accident to strengthen man's control over Nature. Even as late as the middle of the nineteenth century accident and not science was regarded as the fountain-head of invention, and the view that a knowledge of the causes and secret motions of things would lead to "the enlarging of the bounds of human empire to the effecting of all things possible" was scouted as the idle dream of a doctrinaire.
In the year 1896 three important advances were made in man's mastery of his environment. These are associated with the names of Marconi, Becquerel, and Langley. It was in this year that the last-named, long known to the scientific world for his discoveries in solar physics, demonstrated in the judgment of competent witnesses the practicability of mechanical flight. This was the result of nine years' experimentation. It was followed by several more years of fruitful investigation, leading to that ultimate triumph which it was given to Samuel Pierpont Langley to see only with the eye of faith.