66 Rain in WiUiamstown. [July? 



economy of plants. Some have thought that they required water 

 only to live and thrive. This, however, is not so. And yet with- 

 out it, the hopes of the husbandman would fail. It is the great 

 agent in supplying plants with food, and as we have seen is 

 itself a large constituent of all vegetable matter. 



AMOUNT OF RAIN IN WILLIAMSTOWN, MASS., IN 1845. 



You have, once or twice, requested some statistics, relative to 

 the amount of water which annually falls here. It is not until 

 rather recently that I have obtained results altogether satisfactory, 

 taking the whole year together. During the warm months the 

 depth of rain can be easily estimated; but in the winter, or when- 

 ever the moisture falls in the form of hail or snow, the precise 

 quantity can not be ascertained so easily. My present method, 

 and one which appears to answer the purpose very well, is to 

 bring the water into a green-house attached to my study. A 

 single pane of glass is taken from the roof, and a tunnel insert- 

 ed. The lower surface of this, being constantly exposed to the 

 warm air of the room, melts the snow and sleet, as they fall. In 

 this way the difficulty above referred to is obviated. I have mea- 

 sured the quantity which has fallen in a graduated tube. I should 

 a little prefer to let the water fall into a vessel attached to one 

 arm of a balance, and thus find its weight. At present, however, 

 I adopt the other method. I will now give a comparative view 

 of the quantity of w^ater which fell here during the year 1845. 



January, 80 inches. July, 136 inches. 



February, — 63 " August, — 93 " 



March, 72 " September,- 122 " 



April, 49 « October,--- 57 " 



May, 62 " November,- 92 " 



June, 49 " December,- 75 " 



The largest quantity, at any one time, was on the evening of 

 the 18th of September: comparative number, 44, nearly as much 



