24^ DAVENPORT HADKMY OF NATURAL SCIENCES. 



/oology, geology, mineralogy, chemistry, meteorology, astronomy, and 

 the undulatory forces, light, heat, and electricity, and see how largely 

 they contribute to the needs of our daily life, and the requirements of 

 modern civilization. Thus, the discovery of magnetism and electricity 

 has been followed by inventions which have given to humanity the tel- 

 egraph, the telephone, and the electric light. By the telegraph, time 

 and distance have been well-nigh obliterated, and nations, though sep- 

 arated by seas and continents, are now brought into hourly communi- 

 cation, and through the net-work of friendly relations thus woven round 

 the earth, war has almost disappeared from human history. By the use 

 of the telephone an entire community is enabled to engage in familiar 

 conversation as though collected under one roof, and even the inhab- 

 itants of neighboring cities, without leaving their homes,- may carry on 

 with each other the ordinary transactions of business life. Thus, too, 

 the discovery of the expansive powers of steam has been followed by 

 mechanical inventions which have subjected it to human control, and 

 made it "the drudge of civilization." This almost superhuman power 

 now enters into all the industries of life, and, by increasing the pro- 

 ductive power of labor, has elevated the race. It has been estimated 

 that by the use of steam the resources of labor have been augmented 

 a thousand-fold, and that, in the manufactories of Great Britain alone, 

 "the power which steam exerts is equal to the manual labor of four 

 hundred millions of men, or more than double the number of males 

 supposed to inhabit the globe." So, too, by the use of steam in navi- 

 gation, and for operating railroads, and the facilities thus afforded for 

 rapid travel and transportation* trade and commerce have been widely 

 extended over the vacant places of the earth, and thus large value given 

 to hitherto vast unproductive areas. But for the net-work of .railroads 

 which cover our western prairies, these broad tracts now teeming with 

 abundant harvests would be nearly valueless. So, also, researches in 

 optics, with the aid of chemistry, have given us photography, and the 

 Spectrum Analysis, which are among the most important discoveries of 

 recent years. Photography is not alone the artist of society, but, as the 

 aid of modern science, it goes into the far reaches of space to faithfully 

 record the most evanescent of celestial phenomena, and into the depths 

 of the sea to depict the strange secrets for the wondering gaze of man. 

 The spectrum analysis, though less intimately associated with our daily 

 lives, is no less wonderful. It gives us a deep insight into the elements 

 of the earth, and reveals the composition of the heavenly bodies. 

 This, as you all know, is accomplished through the decomposition of 

 light, and thus, by a careful comparison of the spectra of earthly sub- 

 stances with those of the celestial bodies, astronomers have been able 

 to detect many of the materials of which they are composed. So, also, 

 the recent researches in anatomy, physiology, and hygiene, have been 

 of inestimable value to the race. By the information thus acquired 

 concerning the organs of the body, their functions in the economy of 

 life, and their proper care and treatment, ills have been removed, dis- 

 ease brought under control, and life itself greatly prolonged. As a 

 direct result of this scientific progress, it is claimed that "as large 



