Mrecrocraputa, 
in Sand, and{(as ‘twere) finks tothe bottom. Nor can you make:a hole 
in the fide of the Difh, but the {and thall rvx ontiof it to.a level, not an 
obvious property of a fluid body, as fuch, but this dos imitates and all 
this meerly caufed by the vehement agitation of the conteining veffel 5 
for by this means, each fand becomes to have a wibrative or dancing mo 
tion, fo'a¢no other heavier body:can reft on it, unlefs foffein'd by fome 
other on either fide: Nor will it fuffer any Body tobe beneath it; unlefS 
it be a heavier them it felf. Another Inftance of the ftrange loofening 
nature of a violent jarring Motion, or a ftrongand nimble vibrative 
one, we may have from a piece of #row grated:on very ftrongly witha 
file : for ifinto that a pin be ferem’d fo firmand hard, ‘that though it has 
a convenient head toit, .yet itcanby no means be uxfcren'd by the fm= 
- gers; if, fay, you attempt to unfcrew this whilft grated om by the files iv |’ 
will be tound to undoe and turn very eafiy... The firft of thefe Examples — 
manifefts, how.a body aétually divided into {mall parts, becomes:a finid 
And the latter manitfefts by what means. the agitation of heat {0 eafily 
loofens and naties the partsof folid and frm bodies. Nor need we fup- 
pofe heat to be any thing elfe, befides tuch a motion ; for fuppofing we 
could Atechanically produce fuch a one quick and firong enough, we need » 
not {pend fxel to melt a body. Now, thatI do not {peak this altogether 
groundleis, I muft refer the Reader tothe Obfervattons I have made up- 
on the fhining {parks of Steel, for there he fhall find. that the fame effects 
are produced upon{mall chips or parcels of Steel by the flame, and by 4 
quick and violent motions and if the body of fee! may be thus melted 
(as I there fhew it may) I think we have little reafon to doube that al- 
moft azy other may not alfo.. Every Smith can inform one how Sank 
both his Fi/e' and, the Irez grows hot with filime, and if you rb alm 
any two dard bodies together, they will do the fame: And we know, 
that a fufficient degree of heat caules fluidity, in fome bodies much foon- 
‘er, and inothers later; that is, the partsof the body of forme are fo /aofé 
from rit Set and fo uzapt to whee and fo minute and fittle, that a 
very /wall degree of agitation keeps them always in the frate of fluidity. 
Ore Sak Tfappote the shen tit is the spesldbee ‘Le iA 5; In 
which all other bodies do asit were fwim and move; and particularly, 
the Air, which feems nothing elfe but a kind of ti#ure or folution of ter- 
reftrial and aqueous particles azfolwdinto it, and agitated by it, juftas . 
the ténéfure of Cocheneelis nothing but fome finer diffoluble parts of that 
Concrete lick'd up or diffale'd by the fluid water, And from this Notion 
of ir, we may eafily give amore Intelligible reafon how the Air becomes 
fo capable of Rarefaition and Condenfation. For, as in tinttures,one grain 
of fome ftrougly tinging fubftance may fenfibly colour fome hundred thow- 
fand grains of appropriated Liquors,{oas every drop of it has its proportio- 
nate fhare; and be fenfibly ting’d, as Lhave try'd both with Logsoo 
and Cocheneel : And.as ey grains of Salt is able — ne 
zreat a ity,as may be y pracipitations, though not fo cafily 
Geshe bebe oriape > Grthie Air, whichfeems to be but as twere a tinéfure 
ox faline fubftance, diffolo'd and agitated by the finid and agil Zther,may dif- 
perfe 
