MARYLAND GEOLOGICAL SURVF.Y 191 



In the interior of the United States the annual range in monthl)^ mean 

 temperatures (normals) is much greater at many places; for instance, 

 at St. Paul the normal January temperature is 11.3°, July 73.0°, giving 

 a range of 60.7°, as compared with -1 1.8° at Solomons. On the other 

 hand it is much smaller on the west coast of Europe, at Valencia^ Ireland, 

 only 15.1° (January UA° , Ji51y 59.5°). 



'I'lie mean temperature of spring at Solomons is 51°, of summer 77°; 

 autumn 60°, and winter 35°; autumn is therefor^^ 6° warmer than 

 spring. 



The annual march of temperature at Solomons is shown graphically 

 by the upper curve in Figure 8; for comparison the annual curves at 

 Sunn^-side and AVoodlawn are included. The diagram reveals readily 

 to the eye the difference in temperature conditions in various portions 

 of the State. 



Means of the Maximuin and Minimum Temperatures. 



In Tables IX and X will be found the means of the maximum and 

 minimum temperatures. The anual mean maxiinuni is 61.7°, and the 

 mean minimum is 48.7°. The mean of the maximum temperatures 

 during a month rarely exceeds 90°, though it has done so twice at Solo- 

 mons during the past 14 years, on both occasions during the extraordi- 

 narily warm summer of 1900 (July, 1900, 90.2°; August, 91.6°). The 

 mean minimum temperature is likewise rarely below 30°, though this 

 has also occurred twice, namely in January, 1893 (18.5°), and in Feb- 

 ruary, 1895 (19.1°). 



A noteworthy climatic element which should be included in this 

 account is expressed by the difference between the normal mean maxi- 

 mum nnd the normal mean minimum temperatures for each month; 

 this is called the mean daily range, or the non-periodic amplitude. 

 Other important data are. the differences between the highest and lowest 

 temperatures each month under extreme and average conditions, and 

 the absolute ranges, which give an idea of the variability of temperature. 

 These data are given in the following table : 



