EAINS AND EIYEES. Ill 



is in the nortliem hemisphere. This difference as to the average 

 condition of the sea on different sides of the'hne is reconciled by 

 the hj^othesis which reqiiires a crossing at the cahn belts. The 

 vapour which conveys fresh water and caloric from the southern 

 hemisphere to the northern will in part account for this differ- 

 ence both of specific gravity and temperature, and no other hypo- 

 thesis will. This hydrometric difference indicates the amount 

 of fresh water which, as vapom' in the air, as streams on the land, 

 and as cmTents in the sea,* is constantly in transitu between the 

 two hemispheres. All these facts are inconsistent with the sup- 

 position that there is no crossing at the calm belts, and consistent 

 with the hypothesis that there is. It is no argument agaiast the 

 hypothesis that assumes a crossing, to urge our ignorance of any 

 agent with power to conduct the air across the calm belts. It 

 would be as reasonable to deny the red to the rose or the blush 

 to the peach, because we do not comprehend the processes by 

 which the colouring matter is collected and given to the fruit or 

 flower, instead of the wood or leaves of the plant. To assume 

 that the direction of the air is, after it enters the calm belts, left to 

 chance, would be inconsistent with om* notions of the attributes of 

 the great Architect. The planets have their orbits, the stars their 

 com^ses, and the wind " his circuits." And in the construction 

 of om' hypotheses, it is pleasant to build them up on the premiss 

 that He can and has contrived all the machinery necessary for 

 guiding every atom of air in the atmosphere through its channels 

 and according to its circuits, as truly and as surely as He has 

 contrived it for holding comets to their courses and binding the 

 stars in their places. These circumstances and others favouring 

 this hypothesis as to these air-crossings, are presented ia further 

 detail in Chaps. YII. IX. XI. and XII., also § 349. 



289, In obser^dng the workings and studyiag the offices of the 

 The atmosphere to various parts of the physical machinery which keeps 

 Mhfr^'madiilferjrby the world iu ordor, we should ever remember that 

 its operations. [j^ jg ^}2 made for its pm-poses, that it was planned 

 according to design, and arranged so as to make the world as we. 

 behold it : — a place for the habitation of man. Upon no other 

 h}^othesis can the student expect to gain profitable knowledge con- 

 cerning the physics of sea, earth, or air. Eegardiag these elements 

 of the old philosophers as parts only of the same piece of machinery, 



* The water wMcli the rivers empty into the North Atlantic has to find its 

 way south with the currents of the sea. 



