On the Tides of Key West. 313 
I hardly supposed that the numbers representing these changes 
of level would furnish evidence of the two interesting tides o 
long period pointed out by Mr. Airy, (Tides and Waves, Encye. 
Metrop., p. 355;) they do so, however, and in the case of the moon’s 
action, Where the number of averages which can be brought to 
bear upon a single result is considerable, and the observations run 
through various parts of the year, the results bear carrying to 
humerical comparison with the formula. These tides, as far as 
lam aware, have not been developed from observation, though 
certain general analogies pointed to their existence. Dividing 
the numbers showing the daily level of the water into groups of 
nearly fourteen days, each corresponding to the moon’s declina- 
tion from the maximum to the maximum again, and taking the 
mean of each set corresponding to the same declination, we ob- 
tain a series which is the average of twenty-six numbers in 
Which the irregularities of the depressing and elevating action of 
the winds will be eliminated, and in which the sun’s action will 
be nearly the same. This series presents a tolerable regularity 
increasing to a maximum at zero of declination, as shown in 
Plate No. 6, curve No. 1 
numbers which, though less regular than the others, also rise 
towards the zero of declination, as shown in Plate 6, curve No, 2. 
The results of the first series of computations bear very well 
a comparison with the formula given by Mr. Airy: 
tively, and 4 is the latitude of the place, requiring C=O. Those 
of the second present greater discrepancies and require O = 3, con- 
tradicting the former. Though the weight of authority is that 
meteorological tables kept while the tidal observations were made, 
ish means for a complete discussion, which is in progress. I 
Stcoxp Senizs, Vol, XVI, No. 54.—Nov., 1854. 
