C ] 
The atmofphere fuppofed at reft, a loaded de- 
Icending particle muft adl with a force on the par- 
ticles it paftes between, or meets with, fufticient to 
overcome in fome degree their mutual repellency, 
and pufli them nearer to each other. 
A Thus, fuppofing the particles 
o o o A B C D, and the others near 
FO BO CO GO them, to be at the diftance 
o DO o caufed by their mutual repel- 
o o o o Icncy (confined by their com- 
E mon gravity) if A would de- 
fcend to E, it muft pafs between B and C. When it 
comes between B and C^it will be nearer to them than 
before, and muft either have puftied them nearer to 
F and G, contrary to their mutual repellency, or 
pafs through by a force exceeding its repellency with 
them. It then approaches D, and, to move it out of 
the way, muft ad on it with a force fufticient to 
overcome its repellency with the two next lower par- 
ticles, by which it is kept in its prefent fituation. 
Every particle of air, therefore, will bear any 
load inferior to the force of thefe repulfions. 
Hence the fupport of fogs, mifts, clouds. 
Very warm air, clear, though fupporting a very 
great quantity of moifture, will grow tuibid and 
cloudy on the mixture of a colder air : as foggy tur- 
bid air will grow clear by warming. 
Thus the fun ftiining on a morning fog, difftpates 
it. Clouds are feen to wafte in a funftiiny day. 
But cold condenfes and renders viftble the vapour. 
A tankard, or decanter, filled with cold water, will 
condenfe the moifture of warm clear air, on its 
outfide, where it becomes viftble as dew, coalefccs 
into drops, defcends in little ftreams. 
4 
The 
