( 4*9 ) 
isfo juftly performed that in many hundreds of years we 
are fufficiently allured that the Sea has not fenfibly de 
creas'd by the Iofs in Vapour; nor yet abounded by the 
immenfe quantity of frefti it receives continually from the 
Rivers. To demonflrate this Equilibre of receipt and 
Expence rn the whole Sea is a Task too hard for me to 
undertake, yet in obedience to thofe whom I have the 
honour to ferve, I fhall here offer, what to me has hi- 
therto feemed the moft fatisfa&ory Account of this Grand 
Phenomenon: I have formerly attempted to explain the 
manner of the rifing of Vapour by warmth, by (hewing 
that if an Atom of Water were expanded into a Shell or 
Bubble fo as to be ten times as big in Diameter as when 
it was Water, fuch an Atoni would become fpecifically 
lighter than Air, and rife fo long as that Flatus or warm 
Spirit that firfl: feparated it from the mafs of Water 
ftall continue todiflendit to the feme degree 3 and that 
warmth declining, and the Air growing cooler and withal 
fpecifically lighter, the Vapours eonfequently lhall ftopat 
a certain Region of the Air, ot elfe defcend, which may 
happen upon feveral Accounts as I lhall by and by endea^ 
deavour to make out. Yet I undertake not that, this 
is the only principal of the rife of Vapours, and that there 
may not be a certain fort of matter whofe conatus may 
be contrary to that of Gravity: as is evident in Vege- 
tation wherein the tendency of the fprouts is dire&ly 
upwards or againft the Perpendicular. But whatever is 
the true caufe, it is in fa£fe certain, that warmth does fe- 
perate the particles of Water and emit them with a grea- 
ter and greater Velocity as the heat is more and more in* 
tenfs, as is evident in the (team of a boyling Cauldron^ 
wherein likevvife the Velocity of the Afcent of the Va- 
pours does vifibly decreafe till they di [appear, being dif- 
perfed into and affiliated with the Ambient Air, Va- 
pours being thus redkd by warmth, let us for a firft fup- 
pofition, put, that ftte whole furface of the Globe were: 
