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In gages of this form, efpecially when 

 made fufficiently large, Mr. Copland of Dum- 

 fries informs me that he found the lofs from 

 •difperfion nearly, if not entirely, correded. 

 The area of the aperture of one of his fun- 

 nels contains 144 fquare inches, and the other 

 288. He has compared this with one of 16 

 inches, and always found a fmaller than proportional refult 

 from this lafl in windy weather. He fays he has obferved his 

 large fquare gages in ftormy falls, and could obferve nothing 

 driven over after it had ftruck the infide, and was furpnfed to 

 fee fo little loft even during a hail fhower. He recommends 

 gages with fquare apertures in preference to circular or cylindrical, 

 for " from the rotatory motion which the air always takes, 

 when forced over the end of a tranfvcrfely truncated cylinder, 

 and which emits, for that reafon, a whiftling noife, the rain will 

 be carried over the edges of the cylinder, and be almoft entirely 

 prevented from falling into the gage." He foon found, after 

 ufmg fquare ones, that the refults from them were much more 

 ample than from fome others that were kept in the neighbour- 

 hood, which were of a cylindrical form. I generally have a 

 little cup with its mouth downwards, fitted to the neck of the 

 funnel as at A, which will go over the mouth of the bottle; 

 becaufe it is evident that when rain is driven againft the outfide 

 of the funnel, or in confequence of the condenfation of dew 

 upon the outer or under fide of it, more water would be colleaed 

 by the receiver than falls within the area of the funnel, if it 

 was not prevented by a contrivance of this kind. 



I WAS 



