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tlie expenses of balloon ascents, to be undertaken for the 

 purpose of obtaining additional data^ of a reliable character, 

 to serve as a basis for future investigations. The Author, 

 therefore, thought it might be worth while to submit to 

 the Society some results which, although confessedly im- 

 perfect, seem to him to indicate very clearly the existence 

 of a law of distribution of temperature in the higher regions 

 of the atmosphere in the different seasons in different lati- 

 tudes of Europe and Asia, which appears to have hitherto 

 escaped notice, and which seems likely to have an important 

 bearing upon many interesting questions in meteorology. 



From numerous observations made at elevated stations in 

 Europe and India, it has been concluded, 1st, — That the 

 general rate of decrease of the temperature of the atmosphere 

 with increase of height, is least in low, and greatest in high 

 latitudes ; and 2nd, — That the rate of decrease is greatest in 

 the summer and least in the winter months. Some results, 

 however, which the Author obtained in the course of an 

 investigation of the relations which exist between falls of rain 

 and changes in the decrement of temperature on ascending in 

 the atmosphere, and of barometric pressure, in different loca- 

 lities, led him to doubt the general correctness of tUe second 

 of these conclusions, and he has therefore examined all the 

 observations that were accessible to him which seemed likely 

 to throw any light on the subject ; and from the results which 

 he has obtained he shows that there exists in the temperate 

 latitudes of Europe and Asia a belt or zone in which the 

 decrease of temperature, for a given ascent in the atmosphere, 

 is greatest in the winter months, v/hile at stations north or 

 south of this belt, so far at least as observations have yet been 

 made, the decrease is greatest in the summer months. 



This belt passes over Portugal, Spain, Sicily, Southern 

 Italy, the Caucasian provinces, and Southern Siberia; and 

 at places lying within it the changes of temperature produced 

 by cliange of season are greater in the higher than in the 



