Of the JVheel Animal . 281 
The Situation, the Size, the Contraction, 
and Dilatation of the Part we fuppofe to be 
the Heart, all concur in Support of that 
Opinion ; but they can hardly all agree with 
any other of the Vifcera : and as to the Suf- 
penlion of its Motion, lince in the Tortoife, 
the Viper, the Frog, and perhaps many 
other Creatures who become torpid at dome 
Seafons, the Motion of the Heart is fuf- 
pended or unpefceivable for a confiderable 
Length of Time, there is no Abfurdity in 
believing that the fame Thing may happen 
to this XnfeCt, which is fometimes in a tor¬ 
pid or inaClive State as well as they, without 
doing it any Injury. Nay, that the Motion 
of its Heart (whether this Part be it or 
no) mud: unavoidably be fufpended, whilft 
this very Animal is contracted into a Ball, 
and as dry as Dud:, is, I think, highly pro¬ 
bable. 
The Blood or circulating Fluid is fo ab- 
folutely colourlefs in this Creature, that the 
Current of it through the Veflels is undidin- 
guidhable by Glades, however likely it may 
feem* from the ftrong Contraction of the 
Heart, that a Circulation mud: be carried 
on, and that too very brifkly. One fees 
indeed almoft every where a Sort of irregu¬ 
lar Agitation of fome Fluid, which may be 
perhaps the compound Motion of Currents 
running different Ways and forming fuch an 
Appearance, 
