Foreign Vegetables. 379 
The Blood thus expanded, diftends the Arteries 
of the whole Body *, and the Effedls and Appear- 
ances are various, according to the different Bowels 
in which this fudden Rarefadtion is produced. As 
foon as the Blood circulating through the Brain is 
rarefied, the fmall Arteries, being diftended and 
pofTeffing a larger Space, comprefs the nervous 
Canals interwoven with them, more or lefs, accord- 
ing to their greater or leffer Dilatation. The Nerves 
being too much compreffed, a fmaller Quantity of 
the nervous Juice enters into them and flows to the 
Parts : Whence the Fundtions of the Body are not 
fo well performed, the Arteries vibrate more (low- 
ly, though from the rarefied Blood they are more 
than ufually diftended *, and therefore the Pulfe is 
high, but lefs frequent. A preternatural Heat is 
raifed over the whole Body, becaufe the circulatory 
or progrefiive Motion of the Blood being diminifh- 
ed, with an Increafe of Fluidity, its inteftine or 
fermentative Motion, upon which the Heat depends, 
is augmented. From the Decreafe of the Afflux 
of the nervous Juice to the Parts, and of its Re- 
flux from the Parts to the Brain, proceed a Numb- 
nefs of the Limbs, a Diminution of Senfe, and of 
Motion. A Sleep is likewife brought on more or 
lefs deep, as the Nerves, or the Origins of the Nerves 
appointed for the Performance of the animal Func- 
tions, are more or lefs compreffed by the Arteries. 
Laftly, Death fometimes follows, if from too great 
and fudden an Intumefcence of the Arteries, moft 
of the nervous Fibres of the Brain are fo far ftraiten- 
ed, that their Juice can no longer pafs through them. 
It is entirely after the fame Manner that Opium 
eafes Pain : Not that it removes the Caufe of Pain ; 
but becaufe, by hindering the Influx of the ner- 
vous Juice into the Nerves, it prevents the Arrival 
of the painful Senfation, from the Part affedted, at 
the Origin of the Nerves or the Soul. 
From 
