Bauhaus-Universität Weimar

46 OF THE VITAL AND 
N f 
ufually inquired into, nor indeed eafily anfwered ; although the 
fécond feems to admit of a much eaher folution than the fir ft. 
If all the parts and organs exift in miniature in the animalcule in 
femine, it will fcarce be difpuced, that while it fwims in this liquor, 
the fluids are propelled through its veflels by the a&ion of its heart, 
and circulate in the fame manner as in the fœtus in utero. If the 
heart does not exift in the animalcule, but is formed after concep¬ 
tion, then the beginning of its motion mu ft be later. But, be this 
as it will, we know that in impregnated eggs, the animalcule lies 
in a death-like ftate, refembling that of many infe&s, and fome 
larger animals in winter ; and that its heart remains at reft, till by 
the heat of incubation it is roufed into action. After the motions 
of the heart of the chick become vifible, they may be rendered more 
lively or languid by a greater or lefs degree of warmth ; nay be made 
entirely to ceafe by cold, and be as quickly renewed again by 
heat *. Hence it follows, that though it be not certain when the 
heart begins firft to move in nafcent animals, yet the caufe which 
fets it firft a-going, and recommences its motions after being flop¬ 
ped, is heat, which, by rarifying and agitating with an inteftine 
motion the particles of the fluids, enables them, by their Jiimulus, 
to excite the fibres of the heart into contra&ion ; at the fame time 
that it increafes the fenfibility of the nerves, which are benumbed 
by too great a degree of cold. 
SECT. V. 
Of the motions of the alimentary canal, and bladder of urine. 
HAVING thus accounted for the alternate contra&ion and re¬ 
laxation of the heart ; we come next to inquire into the caufe 
of the other involuntary motions ; and {hall begin with thofe of the 
alimentary canal. 
In deglutition, the contra&ion of the mufcles which draw up the 
larynx 
# Harvey de generation, animal, exercitat. 17.
        

Nutzerhinweis

Sehr geehrte Benutzer,

aufgrund der aktuellen Entwicklungen in der Webtechnologie, die im Goobi viewer verwendet wird, unterstützt die Software den von Ihnen verwendeten Browser nicht mehr.

Bitte benutzen Sie einen der folgenden Browser, um diese Seite korrekt darstellen zu können.

Vielen Dank für Ihr Verständnis.