MicROGRAPHiIA, 
piecess for all the Springs of the feveral parts are fet at liberty, which 
37 
immediately extricate themfelves and fly afunder every way 5 each part - 
by its {pring contributing to the darting of it {elf and fome other contigué 
ous part. But if this drop be heat fo hotasthat the parts by degrees can 
unbend themfelves, and be fettled and annealed in that pofture , and be 
then fuffered gently to fubfide and cool; The parts by this nealing lo 
fing their {pringinefs, conftitute a drop of a more foft but lefs brittle texs 
ture,and the parts being not at all under a flexure, though any part of the 
middle or Pith TEE E bebroken, yet will not the drop at all fly to pieces 
as before. 
- This ConjeGure of mine I fhall indeavour to make out by explain! 
ing rer particular Affertion with analogous Experiments : The Affertioné 
arethefe, . : oa 
Firft, That the parts of the Glafs, whilft in a fluid Confiftence and 
hot , aremore rarified, or take up thoreroom, then when hard and 
cold. eee | Zoli bre 
Secondly, That the parts of the drop do fiffer a twofold contras 
éion. 
Thirdly, Thatthe dropping or quenching the glowing metal inthe 
Water makes it of a hard, {pringing, and rarified texture. 
Fourthly , That there is a flexion or fotce rertiaining upon the parts 
of the Glafs thus quenched , from which they indeavour to extricate 
themfelves. _ be : 2 Jose da 
Fifthly, That the Fabrick of the drop, that is able to hinder the parts 
from extricating themfelves, is azalogws to that of an Arch. eo 
Sixthly, That the fudden flying afunder of the parts proceeds frorti 
their fpringinefs. " 
Seventhly, That a gradual heating and cooling does anneal or reduce 
the parts of Glafstoa texture that is more loofe; and eafilier to be broé 
ken, but not fo brittle; sg 
That the firft of thefe is true may be gathered from this, That Hedt i 
a property of 2 body arifing fromthe motion or agitation of its parts 5 and 
therefore whatever body is thereby roucht muft neceflarily receive forte 
oy of that miotion,whereby its parts will be fhaken and agitated, and fo 
y degrees free and extricate themfelves from one another , and each 
part fo moved does by that motion exert a conatus of protruding and dif 
placing all the adjacent Particles: Thus Air included ina vefiel, by be- 
ing heated will burft ito pieces. Thus haveI broke a Bladder held 
over the fire in my hand, with fach a violence and noile , that it almoft 
made me deaf for the ptefent,and much furpafied the hoife of a Muskett 
The likehave I done by throwing into the fire finial) gla(s Bubbles her+ 
metically fealed , witha little drop of Water included in themy © Thus 
Water alfo,or any other Liquor,included ina convenient veflel,by being 
warmed , manifeftly expandsit felf witha very great violence, {o asto 
break the ftrongeft veGél, if when heated it be narrowly imprifoned es 
: ee iis 
* 
