318 THE PHYSICAL GEOGRAPHY OF THE SEA 



— the making, as it were, of efforts by fits and starts to keep up 

 to time in the performance of its manifold offices — are not unfre- 

 quent, nor are they inaptly likened to spasms. There are some 

 remarkable throes in the sea which I have not been able wholly 

 to account for. Near the equator, and especially on this side of 

 it in the Atlantic, mention is made, in the " abstract log," by al- 

 most every observer that passes that way, of " tide-rips," which 

 are a commotion in the water, not unlike that produced by a con- 

 flict of tides or of other powerful currents. These "tide-rips" 

 sometimes move along with a roaring noise, and the inexperienced 

 navigator always expects to find his vessel drifted by them a long 

 way out of her course ; but when he comes to cast up his reck- 

 oning the next day at noon, he remarks with surprise that no cur- 

 rent has been felt. 



914. These tide-rips are usually found in the neighborhood of 

 the equatorial calms — that region of constant precipitation. And 

 hence, if currents at all — if so, they are very superficial — I have 

 thought they might be streams of rain water, which old seamen 

 tell us they have dipped up there fresh from the sea, running oft'. 

 This conjecture, however, does not satisfy the phenomenon in all 

 of its aspecte. It is sometimes described as starting up in a calm, 

 and then approaching the vessel with great waves and a great 

 noise ; it seems threatening enough to excite a feeling of appre- 

 hension in the minds of seamen, for it looks as if it would dash 

 over their frail bark as it lies wallowing in the sea, and helplessly 

 flapping its sails against the masts. 



915. Captain Higgins, of the Maria, when bound from New 

 York to Brazil, thus describes, in his abstract log, one of these 

 "tide-rips," as seen by him, 10th October, 1855, in N. lat. 14°, 

 W. long. 34° : 



"At 3 P.M. saw a tide-rip; in the centre, temp, air 80°, wa- 

 ter 81°. From the time it was seen to windward, about three to 

 five miles, until it had passed to leeward out of sight, it was not 

 five minutes. I should judge it traveled at not less than sixty 

 miles per hour, or as fast as the bores of India. Althougli we 

 have passed through several during the night, we do not find they 

 have set the ship to the westward any ; it may be that they are so 



