2 
The Stomachs and Gnu. 
fo in Erutlation, only with lefs force. For the performance 
of which Actions, Two Mufcules or Mufcular Membranes 
are yet requifite \ and thofe platted and interchanged, as 
hath been defcrib'd : That is, by a double Plat of the Fi- 
bers of both 5 whereby half the nether Membrane on the 
one fide the Gulet, becomes half the upper Membrane on 
the other fide : and fo vice verfa, in fpiral rounds through- 
out. To the end, That the Gulet being hereby contracted 
in one part, and dilated in the next,might at the fame time, 
thruft forward, and let pafs, any body therein contained : 
and that the faid Contractions and dilatations might be 
more eafily and regularly made, and by reciprocal Vndula- 
tionsy carry'd on from one end of the Gulet to the other. 
Thefe Vndulations, in the Gulet of a fforfe, when he drinks, 
are very plainly feen. 
And that this Vndulation may be made with more fpeed, 
it is obfervable, That the faid Mufcular Fibers are not con- 
tinued by a clofe, but very oblique or open fpiral Line. 
Whereby, as the fpiral Rounds or Circuits, fo the Undula- 
tions, are the fewer 3 and confequently, not flowly ( as in 
the Guts) but much fooner finifhed. 
Hence it is, That a Cat hath fo difficult a fwallow, the 
meat commonly feeming to flick in her Throat. Not from 
the fmallnefs of her Gulet 3 but for that in the longer half 
of it, the Mufcular Fibers are continued in fo clofe a fpiral 
Line, as rather tofeem Annular. Whereby, the Vndulati- 
ons of the Gulet are more flowly and difficultly made. So 
that a more difficult fwallow, being one thing neceflary to 
make her not greedy, but patiently to watch for her Prey 5 
Nature hath therefore contriv'd her Gulet for that pur- 
pofe. 
The Nervous Membrane, or ( as in fome Graminivorous 
Animals it may be calPd ) Corpus Nervofum, hath hitherto 
been thought to ferve only for fenfe. Dr. Willis Con- 
jectures, That it is alfo the Inftrument of fome certain mo- 
tions of expanfion in 0 [citation and Preternatural Inflation : 
which is all he faith. 
But to Me, it fecmeth , That it Cooperates with the 
Mufcular Membrane to all the Natural Motions of the 
Gulet, in Deglutition, Vomition, and Erutlation. And, to 
fpeak properly, That 'tis nothing elfe but a HOLLOW 
TEN- 
