EXPLANATION OF OCEAN TEMPERATURE CHART No. 25. 



PETIT MANAN LIGHT-HOUSE, MAINE. 

 Observer: George L. Upton. 



Location of station.— rotit Maaau light-houso is located ou the soathernmost of a group of low, rocky islets, known, 

 collectively, as Petit Manan Island. These islets arc situated off the western entrance to Pigeon Hill Bay, near 

 Gouldsborough, Mc., and are distant about 2 miles from the nearest point of the mainland. They are immediately 

 surrounded by lodges and shoals, but within a distance of 8 miles to the southward deiiths of (W fathoms occur. The 

 light is 27 miles NE. J N. from Mount Desert Ruck light-house. 



Geographical })08ition.—hatUude, 44° 22' O:?" N. ; longitude, 67° 51' 51" \V. 



Depth of water. — Eight to 15 fathoms. 



Bange of temperature (March 1 to January 1).— Air, 50" (20° to 70°) ; surface, 27°.5 (31° to 5a°.5). 



The range of air temperature is the same as at Mount Desert Rock, but with the maximum and minimum temper- 

 atures each 5J degrees lower. Excluding the year 1^83, the maximums of air temperature would be nearly the same 

 at both places. The surface maximum is 4 degrees higher at this station. The surface curves for 1881 to I'-'SS, inclii 

 sive, are fully as irregular as at Mount Desert Rock, and there is the same lack of uniformity between the different 

 years, but the variations do not in any way correspond at the two stations, and the conditions by which they were 

 produced were evidently not common to both. There is much greater correspondence between the years XSf^A and 

 1885. 



Table showing tiie direction of the winds, liy ijnadrants, for each muntli of the ijvtir, being the vieans office y<ara' observations. 



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