278 THE PHYSICAL GEOGRAPHY OF THE SEA. 



sider it now. But the sailor at sea observes phenomena and wit- 

 nesses operations in the terrestrial economy which tell him that, 

 in the beautiful and exquisite adjustments of the grand machinery 

 of the atmosphere, the clouds have other important offices to per- 

 form besides those merely of dispensing showers, of producing 

 the rains, and of weaving mantles of snow for the protection of 

 our fields in winter. As important as are these offices, the philo- 

 sophical mariner, as he changes his sky, is reminded that the 

 clouds have commandments to fulfill, which, though less obvious, 

 are not therefore the less benign in their influences, or the less 

 worthy of his notice. He beholds them at work in moderating 

 the extremes of heat and cold, and in mitigating climates. At 

 one time they spread themselves out; they cover the earth as 

 with a mantle ; they prevent radiation from its crust, and keep it 

 v/arm. At another time they interpose between it and the sun ; 

 they screen it from his scorching rays, and protect the tender 

 plants from his heat, the land from the drought; or, like a gar- 

 ment, they overshadow the sea, defending its waters from the in- 

 tense forces of evaporation. Having performed these offices for 

 one place, they are evaporated and given up to the sunbeam and 

 the winds again, to be borne on their wings away to other places 

 which stand in need of like offices. Familiar with clouds and 

 sunshine, the storm and the calm, and all the phenomena which 

 find expression in the physical geography of the sea, the right- 

 minded mariner, as he contemplates "the cloud without rain," 

 ceases to regard it as an empty thing; he perceives that it per- 

 forms many important offices ; he regards it as a great moderator 

 of heat and cold — as a "compensation" in the atmospherical 

 mechanism which makes the performance perfect. Marvelous are 

 the offices and wonderful is the constitution of the atmosphere. 

 Indeed, I know of no subject more fit for profitable thought on 

 the part of the truth-loving, knowledge-seeking student, be he 

 seaman or landsman, than that afforded by the atmosphere and 

 its offices. Of all parts of the physical machinery, of all the con- 

 trivances in the mechanism of the universe, the atmosphere, with 

 its offices and its adaptations, appears to me to be the most won- 

 derful, sublime, and beautiful. In its construction, the grandeur 

 of knowledge is displayed. The perfect man of Uz, in a moment 

 of inspiration, thus bursts forth in laudation of this part of God's 



