OCEAN TEMPERATURES AND CURRENTS. 23/ 



moving to the northeast, and were, undoubtedly, in one 

 of the smaller outlying bands of the Gulf Stream. 



You will also notice from the table that the tempera- 

 ture of the water decreases, as the water moves onward. 



Distance from the source of heat, contact with the 

 colder air and water, and radiation to the air are without 

 doubt the main factors in this decrease. Notwithstand- 

 ing this decrease, the stream still has a wonderful amount 

 of power left to modify climate. According to Croll, 

 this current removes from the equator each day an 

 amount of heat equivalent to 154,959,300,000,000 foot 

 pounds. This is equal to 325.000 horse power per second. 

 Now, if we should wish to produce the same effect by 

 burning coal, we should have to use 336,000,000 tons of 

 coal per day, and when we remember that the total out- 

 put of the mines of America is but about 100,000,000 

 tons in a year, we will see that we have here a very 

 abundant supply of heat at work, modifying our climate 

 to an extent utterly beyond our imagination's power to 

 grasp. 



Let me now speak a few words upon the subject of 

 the modification of the course of these currents. They 

 are the great means of exchange between the waters 

 of the equator and those of the poles. How are these 

 circuits established, and why should they have this orbit- 

 like course in each of the oceans, irrespective of the 

 size or shape of the ocean ? At first, it was supposed 

 that elevations upon the bed of the oceans controlled 

 their course, but the soundings of modern times have 

 done away with this idea completely. We must have 

 recourse to the law of inertia to explain this phenomenon. 

 As the warm water of the equator starts from the equa- 



