510 PHILOSOPHICAL TRANSACTIONS. [aNN0 1731. 



rides. On immersing the ball of his thermometer into ice, the mercury falls 

 47_3j. inches; and into boiling water, it rises 63-rV inches 10 dec. 



After premising these things, the following table exhibits the quantities of 

 rain-water and of melted snow collected together, as the sums corresponding to 

 each year, viz. 



In the years 17'25, i72(), 1727, 1/28, 1720, 1730. 

 The inches 29.99, 23.33, 46.41, 52.83, 35.42, 34.30. 



When the same months of these six years were collected together into one 

 sum ; it was found that the least quantity of water fell in the month of February; 

 as not exceeding 7-74 inches; and that the greatest quantity fell in the month 

 of October, which was 30.57 inches. 



Besides, S. Poleni collected apart the numbers of the quantities of water, 

 that fell in each season of the year; reckoning the seasons for each year, in 

 such manner as to refer the beginning of winter to the 10th of December of 

 the preceding year; and thus beginning the rest of the seasons at the lOth of 

 March, June, and September, respectively. The sums found are exhibited n 

 the following table. 



Sum 39.58 52. 1 58.0 1 74.57 



From which table it is evident that the respective quantities of water, in 

 summer and autumn for every year, was greater than that in winter and spring. 



If the respective quantities for each season be collected into one sum, and 

 these sums be compared together, it will easily appear, that the increments 

 proceed in the same order as the seasons do, beginning from winter; that is, 

 that the least quantity of water is had in winter, a greater in spring, a still 

 greater in summer, and the greatest of all in autumn. 



If the height of the barometer, not of each year, but of all the 6 years, be 

 collected into one sum only, the mean height of the barometer, corresponding 

 to each day of all the said years, will be found to be 29.7 inches. 



And if the heights of the thermometer, not of each year, but of all the 6 

 years, be collected into one sum only, the mean height of the thermometer, 



