THE ATMOSPHERE. 89 



an insight, though never so dim, into any one of the offices for 

 Their influences up- which any particular part of the physical machinery 

 on tiie mind. ^f Qur planet was designed by the Great Archi- 



tect, the mind is enriched with the conviction that it has com- 

 prehended a thought that was entertained at the creation. For 

 this reason the beautiful compensations which philosophers have 

 discovered in terrestrial arrangements are som'ces of never-failing 

 wonder and delight. How often have we been called on to admire 

 the benign provision by which fi^esh water is so constituted 

 that it expands from a certain temperature do^^^l to freezing 1 

 We recognize in the formation of ice on the top instead of at the 

 bottom of freezing water, an arrangement which subserves, in 

 manifold w^ays, wise and beneficent purposes. So, too, when w^e 

 discern in the upper sky (§ 234) currents of wind arranged in 

 strata one above the other, and running hither and thither in dif- 

 ferent dnections, may we not say that we can here recognize also 

 at least one of the fore-ordained offices of these upper winds ? That 

 by sending dovm fresh air and taking up foul, they assist in main- 

 taining the world in that state in which it was made and for which 

 it is designed — " a habitation fit for man ?" 



2-1:1. The phenomena of cold and warm *' spells" are often 

 The effect of down- observcd in the United States, and I suppose in other 

 producing cold.' parts of the world also ; and here in these downward 

 currents we have the explanation and the cause of sudden and 

 severe local changes in the weather. These belts often lie east and 

 west rather than north and south, and we frequently have much 

 colder or hotter weather in them than we have even several degTees 

 to the north or to the south of them. The conditions requii^ed for one 

 of these cold " snaps " in America appear to be a north or north-west 

 wind of considerable breadth from west to east. As it goes to the 

 south, its tendency is, if it reach high enough, to bring do^^Ti cold air 

 from above in the manner of the trade-winds (§238) ; and when the 

 air thus brought down chances to be, as it often is, dry and cold, 

 we have the phenomenon of a cold belt, with wanner vreather both 

 to the north and the south of it. AVhile I ^mte the thermometer 

 is —4^ in Mississippi, lat. 32°, and they are having colder weather 

 there than we have either in Washington or Cinciimati, 7° farther 

 to the north. 



242. The winter "northers " of Texas sometimes bring down the 

 The winter northers cold air there mtli terrific efiect. These bitter cold 

 ^^ ^''''''''- Vvdnds are very severe at Kueces, in the coast countiy, 



