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XLVII. Of the different ^^a?ttities of Rain ^ 
which aj)pear to fall^ at different Heights^ 
over the fa??ie Spot of Ground, By 
William Heberden, M, D, F, R. S, 
Read Dec. 7, y4 COMPARISON having been 
1769. made between the quantity of rain, 
which fell in two places in London, about a mile 
diftant from one another, it was found, that the rain 
.in one of them conftantly exceeded that in the other, 
not only every month, but almoft every time that it 
rained. The apparatus ufed in each of them was 
very exadl, both being made by the fame artift j and 
upon examining every probable caufe, this unex- 
pedfed variation did not appear to be owing to any 
midake, but to the condant ededt of fome circum- 
dance, which not being fuppofed. to be of any mo- 
ment, had never been attended to. The rain-gage 
in one of thefe places was fixed fo high, as to rife 
above all the neighbouring chimnies 5 the other was 
confiderably below them and there appeared reafon 
to believe, that the difference of the quantity of rain 
in thefe two places was owing to this difterence in. 
the placing of thc,veffel in which it vvas received. A. 
funnel was therefore placed above the highed 
chimnies,, 
