300 THE PHYSICAL GEOGRAPHY OF THE SEA. 



rain will be sent in due season we are assured from on high ; and 

 when we recollect who it is that "sendeth" it, we feel the convic- 

 tion strong within us, that He that sendeth the rain has the winds 

 for his messengers ; and that they may do his bidding, the land 

 and the sea were arranged, both as to position and relative pro- 

 portions, where they are, and as they are. 



551. It should be borne in mind that, by this hypothesis, the 

 The Red Sea and its southcast tradc-wiuds, after they rise up at the equa- 

 '^"P''^'^- tor (Plate I.), have to overleap the northeast trade- 

 winds. Consequently, they do not touch the earth until near the 

 tropic of Cancer (see the bearded arrows, Plate VII.), more fre- 

 quently to the north than to the south of it ; but for a part of ev- 

 ery year, the place where these vaulting southeast trades first 

 strike the earth, after leaving the other hemisphere, is very near 

 this tropic. On the equatorial side of it, be it remembered, the 

 northeast trade-winds blow ; on the polar side, what were the 

 southeast trades, and what are now the prevailing southwesterly 

 winds of our hemisphere, prevail. Now examine Plate YII., and 

 it will be seen that the upper half of the Ked Sea is north of the 

 tropic of Cancer ; the lower half is to the south of it ; that the lat- 

 ter is within the northeast trade-wind region; the former, in the 

 region where the southwest passage winds are the prevailing 

 winds. The River Tigris is probably evaporated from the upper 

 half of this sea by these winds ; while the northeast trade-winds 

 take up from the lower half those vapors which feed the Nile with 

 rain, and which the clouds deliver to the cold demands of the 

 Mountains of the Moon. Thus there are two " wind-roads" cross- 

 ing this sea: to the windward of it, each road runs through a 

 rainless region ; to the leeward there is, in each case, a river rained 

 down. The Persian Gulf lies, for the most part, in the track of 

 the southwest winds ; to the windward of the Persian Gulf is a 

 desert ; to the leeward, the Eiver Indus. This is the route by 

 which theory would require the vapor from the Red Sea and 

 Persian Gulf to be conveyed, and this is the direction in which 

 we find indications that it is conveyed. For to leeward do we 

 find, in each case, a river, telling to us, by signs not to be mis- 

 taken, that it receives more water from the clouds than it gives 

 back to the winds. 



552. Is it not a curious circumstance, that the winds which 



