t/NITEB STATEjS, 



ivise from one day to another, nay, very fr^quently^ 

 in the course of the same day. This is observed 

 particularly in the middle states, as Maryland, Penn- 

 sylvania, and the south part of New York, and more 

 in the f^at country than on the mountains : no doubt, 

 because these middle states, placed between two op- 

 posite atmospheres, that of the pole and that of the 

 tropics, are the theatre of the perpetual contest be- , 

 tween the large masses of cold and hot air. 



It appears that the climate of Pennsylvania, .says 

 Dr. Rush, is a compound of most of the climates iix 

 the world. Here we have the moisture of Britain 

 in the Spring, the heat of Africa in Summer, the tem- 

 perature of Italy in June, the sky of Egypt in the ' 

 Autumn, the cold and snows of Norway, and the ice 

 of Holland, in the Winter, the tempests, in a certain 

 degree, of the We.st Indies in every season, and the 

 variable v^inds and weather of Great Britain in eve*» 

 ry month of the year. 



In the course of our Winters, the Doctor farther 

 observes, particularly in January and P^ebruary, there 

 frequently happen variations of 14, 18, and even 28 

 degrees of Fahrenheit, from cold to hot, or from hot 

 to cold, in less than eighteen hours, by which the 

 health is considerably affected. In four and twenty 

 hours between the 4th and 5th of February, 1788^ 

 the mercury fell from 37 to 4 1-2 degrees below 

 €, a ifference of 41 1-2 degrees. At other time^, 

 the south and south-east winds, bringing on a heat of 

 54 or 58 degrees, occasion a sudden thaw; and this 

 temperature, continuing for some days, has been 

 known to induce premature vegetation, and occasion 

 peach-trees to blossom in the month of Februarjr 'j 



