578 THE POPULAR SCIENCE MONTHLY. 



Bcientific questions with which an intelligent government has to deal 

 would almost fill a volume ; for present purposes, the merest summary- 

 must suffice. 



Beginning with the defensive branches of our public service, we 

 find that both the army and navy have much to demand of science. 

 At West Point and Annapolis, at public expense, the cadets are taught 

 the elements of science ; and these elements, with certain limitations, 

 are afterward professionally applied. In the Ordnance Corps, at the 

 Torpedo Station, etc., men of science are actively engaged upon prob- 

 lems which involve both applications of known facts and explorations 

 into the unknown ; and upon the results of their experiments and stud- 

 ies the safety of the nation may depend. The army engineers have to 

 deal with many other scientific questions, such as relate to the build- 

 ing of fortifications, the strength of materials, and so forth ; and dur- 

 ing times of peace they have also charge of river and harbor improve- 

 ments throughout the land. These improvements, as at Hell Gate or 

 along the Mississippi, involve applications of rigidly scientific methods, 

 and require familiarity with the latest instrumental improvements. 

 Allied to this work is that of the Hydrographic Ofiice, which perfects 

 the knowledge of our harbors ; thus aiding navigation, and at the 

 same time furnishing data which may be available for purposes of 

 defense. The army and navy both maintain strong medical corps ; 

 and here, apart from the mere treatment of wounds or diseases, much 

 useful work relating to medical science is done. The nature of an 

 epidemic is investigated, the water-supply of a fort examined, the 

 sanitary condition of a ship regulated, medical statistics accumulated, 

 and 60 on. In the navy, compasses have to be studied with reference 

 to the magnetic character of their surroundings on shipboai*d ; and an 

 observatory, famous among the observatories of the world, is main- 

 tained. Here are found the data necessary for navigation, standard 

 time is furnished, chronometers are rated, and the highest investiga- 

 tions in pure astronomy are carried forward. Finally, both army and 

 navy call upon chemical science to protect them against frauds. Sup- 

 plies are purchased, either in foods or medicines, iron for ordnance, 

 paints and varnishes for ship-yards, clothing for men, etc. ; and the 

 question whether the articles provided are of proper quality is con- 

 stantly being raised. So analyses are made ; and for this purpose 

 each branch of the service maintains laboratories, and chemists are 

 kept continually at work. 



Attached to the army, and yet having no definite relations to mili- 

 tary work, we find the Weather Service. This fairly represents a class 

 of organizations which protect, not the nation as such, but rather the 

 industries of the people. It warns the ship-owner of a coming storm, 

 or cautions the fruit-grower or sugar-planter against a cold wave, and 

 so assists in making industry surer of a fair return. A similar purpose 

 is fulfilled by the Lighthouse Board, which, attached to the Treasury 



