C 545 ) 
Lungs with the point or edge of your knife. This done, put in 
your finger, and with yburnailfeparatethe Nerve ^ which pafieth 
along the fide of the Pericardium toward the Diaphragm . T hen 
put ina Probe ^ a little inverted at the end like a hook, and ap- 
prehend th e Nerve , and pull it to^the Orifice of the Breaft, and 
cut it off, and fow the hole up very' dole. Do the fame on the 
other fide, and prefently let the Dog loofe, and you will plainly 
fee him draw his breath exadfly like a Wind-broken Horfe : Which 
yet you will fee plainer-, if you run him a little ina firing after he 
Is cut. But that any one may perform this Experiment the eafi- 
er, let him firft take notice, how the Nerves of the Diaphragme 
pafs along on each fide of the Pericardium in a dead Animal, be- 
fore the trial be attempted in a Living one. 
The moft obvious obfervations from this- Experiment, are .• 
1, That the whole manner of Respiration is quite alter’d. For, 
as in a found Animal, in Infpiration the Belly fwells by the lifting 
up the Bowels by the Contraction of the Diaphragme $ and in 
pxfpiration the Belly falls by the Relaxing of the fame : In a 
wind-broken Dog or Horfe ’tis quite contrary. For in them it is to 
be feen plainly, that when they draw their breath, ^eir Belly is 
drawn in very lank and fmall, and when they breathy; their Bel- 
ly is relaxt and fwells again. 
2. It being certain, that the Lungs do not mo ve of them f elves ^ 
at all, but wholly depend upon the Expanfion of the Thorax by 
the Intercoflal Mufcles, and the Diaphragme ; by this Experiment 
it doth appear, how much the fwgle motion of either of them doth 
particularly contribute to Refpiration. For , all Infpiration being ^ 
made by the Dilatation of the Thorax , and that Dilatation being 
cauf ed partly by the Intercoflal Mufcles drawing up the Ribs, and 
partly at the fame time the Diaphragme by its Contraction draw- 
ing downward the lower fmall Ribs, to which ’tis joyned, and alfo 
lifting up the Fifcera of the lower Belly, by which they dojoyntly 
make all the fpace, they can, for the Air to come in and diftend 
the Lungs: It muft hence neceifarily follow , that the Intercoflal 
Mufcles and the Diaphragme being conftituted for two difiant Em- 
ployments (though both to the fame end) and neither being able 
to perform the others Office , where one ceafeth from it’s work, 
the' other for the exigence of Nature mufitake more pains to 
K k k 3 fupj>lx 
