EXPLANATION OP OCEAN TEMPERATURE CHART No. 24. 



MOUNT DESERT EOCK LIGHT-HOUSE, MAINE. 

 Observers : Amos B. Ne-wman, Jaiies A. Morris, Thomas Milan. 



Location of station. — Mount Desert Eock is a small, barren islet, 34 railes E. f N. from Matinicus Eocl:, and 

 about 18 miles off Mount Desert Island. The rock is enrrounded wltb deep Trater, the depths ranging from 50 to 95 

 fathoms ■within a radius of 5 miles. 



Geographical i)osiHo».— Latitude, 43° £8' O5" N. ; longitude, GS° 07' 44" W. 



Depth of water. — Two to 10 fathoms. 



Bange of temperature (March 1 to January 1).— Air, 50° (25°..'i to 75°.5) ; surface, 21°.5 (33° to 54°.5). 



This station presents the same surface range as Matinicus Eock, with practically the same maximum and mini- 

 mum temperatures, but the surface curves are less regular and not uniform for aU the years (especially from 1881 to 

 1883, inclusive), sometimes shovring differences of 10° to 12° in corresponding periods. The maximum air tempera- 

 ture is 2° higher than at any other station in the Gulf of Maine, excepting Thatcher's Island, Brenton's Eeef light- 

 ship being the first station to the south with which it corresponds closely in this respect. The maximum air tem- 

 perature at Matinicus Eock, the nearest station to the west, is 10° lower than at Mount Desert Eock. Excluding, 

 however, the year 1883, in which the summer temperature was far above those of the two ijrevious years, the maxi- 

 mum air temperature of this station would be only 68°. 5. 



Table slioicing the direction of the winds, by quadrants, for each month of the year, being the means of five year^ observations. 



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