Chase.] ^JQ [July. 



I think the above table will be found suggestive of valuable infer- 

 ences, of which the following are perhaps among the most important. 



1. That the apparent osculation of the solar and residual curve 

 near the hours of high barometer may perhaps be owing to ^ethereal 

 resistance. 



2. That the cumulative action of the sun upon the air and oether, 

 may possibly render the disturbing influence of its attraction upon 

 the atmosphere even greater than that of the moon. 



3. That the paradoxical assumption of those who advocate the 

 temperature theory of the quarter-daily tides, that a dependent re- 

 lation can exist between the barometrical changes and the changes 

 of temperature, which '< appears to be direct during the morning 

 hours, and inverse during those of the day and evening,"* is unne- 

 cessary, useless, and unphilosophical. 



4. That in intertropical and medium latitudes, the average daily 

 barometric tide which is attributable to variations of temperature is 

 smaller than the rotation tide. 



5. That there is but one high and one low temperature tide in 

 twenty-four hours. 



6. That the effects of temperature upon atmospheric pressure 

 reach their maximum in the evening, when the aerial absorption of 

 heat from the sun ceases to be in excess of its radiation, and their 

 minimum in the morning, when radiation ceases to be greater than 

 absorption. 



7. That the daily temperature tide increases, while the rotation 

 tide diminishes, as we approach the poles. 



8. That, in consequence of rotation, there should be a slight ten- 

 dency to vertical ascending currents at 4h. and 16h., and descending 

 currents at lOh. and 22h. 



9. That whatever modifications the table may require, there can 

 be no doubt of the existence of the three tides, with maxima and 

 minima near the times specified, or of the possibility and desirability 

 of accurately determining their magnitude. 



2, and 3 hours from the mean tide. This would reduce the quarter-daily residual 

 tide at St. Helena, to the following form : 



If this residual be added to the preceding column, it gives a result accordant 

 with the 6th inference, except two disturbances, which, I think, can be easily ex- 

 plained, one at midnight, and the other in the hottest part of the day. 



* James Hudson, Phil. Trans., 1832. 



