APPENDIX. 



293 



the turn of stream for the time of high water, and registering 

 or calculating observations erroneously, that little dependence can be 

 placed in at least one-third of those hitherto recorded. On this 

 account chiefly, though partly to simplify the question, I have not 

 hoped to be much nearer the mark than half an hour in this dis- 

 cussion, discarding fractions as much as possible, and attempting 

 only to avoid errors of material consequence. 



Looking at the Atlantic, as represented on a globe, we see that 

 Newfoundland and the adjacent coasts are so placed as to receive 

 tidal impulses from the Arctic Sea, North Atlantic Ocean, the 

 tropical part of the North Atlantic and the gulf stream : besides 

 which, no doubt, a derivative from the equatorial zone is felt there. 



It is high water at the east side of the Atlantic, from the 

 Canary Islands to Scotland, within an hour or two of the same time, 

 on the salient points of the coast, namely, at about 4h. ; and if the 

 opposite coast were straight, like that of Chile, and uninfluenced by 

 derivative tides or by currents, we might expect that it would be high 

 water there at about 7h., allowing that the tide-wave moved as it is 

 found to do generally. But it is high water at about Ih., from 

 30° to 40,° the times increasing northward from 40° N. to the Bay 

 of Fundy, and also increasing southward from 50° N. to that bay, 

 where, as every sailor knows, the tides rise higher than in any 

 other part of the world. This sequence of times, each ending in 

 about 43° N., the adjacent gulf stream, (an immense river in the 

 ocean), and an accumulation of water in that corner higher than is 

 known any where else, show that we cannot there expect to find data 

 for tidal rules. In that quarter is evidently a marked exception, 

 caused by the conflux of at least two primary tides, two derivatives, 

 and a powerful current, aided by the peculiar configuration of the 

 land. 



In the Mediterranean it is supposed by m.any persons that there is 

 no ebb and flow ; but Captain Smyth, who surveyed so much of its 

 shores, informs me that he found a tide, small certainly and appa- 

 rently not governed by the moon, but regular. I have myself noticed 

 a small rise and fall there ; and the current, caused by tide, in the 

 Faro of Messina, is well known. 



As the moon passes over the Indian Ocean, the natural efl'ect of 

 her attraction must be to accumulate the waters, and draw the wave 

 so caused after her, as in other places : but while that ocean is obey- 



