324 STOMACH AND INTESTINES. SECT. XXV. 7. 8. 



beef or mutton, are faid to have vomited many 

 Jiours afterwards, when they have been told of the 

 impofition. 



I have been told of a perfon, who had gained a 

 voluntary command over thefe inverted motions of 

 the ftomach and throat,' and fupported himfelf by 

 exhibiting this curiofity to the public. At thefe 

 exhibitions he fwallowed a pint of red rough goofe- 

 berries, and a pint of white fmooth ones, brought 

 them up in fmall parcels into his mouth, and re- 

 ftored them feparately to the fpectators, who called 

 for red or white as they pleafed, till the whole were 

 re-delivered. 



7.' At the fame time that thefe motions of the 

 ftomach and throat are ftimulated into inversion, 

 fome of .the other irritative motions, that had ac- 

 quired more immediate connexions with the fto- 

 mach, as thofe of the gaftric glands, are excited 

 into ftronger action by this alTociation ; and fome 

 other of thefe motions, which are more eafily ex- 

 cited, as thofe of the gaftric lymphatics, are invert- 

 ed by their aflbciation with the retrograde motions 

 of the ftomach, and regurgitate their contents, 

 and thus a greater quantity of mucus, and of lymph, 

 or chyle, is poured into .the ftomach, and thrown 

 up along with its contents. 



8. Thefe inversions of the motion of the ftomach 

 in vomiting are performed by intervals, for the 

 fame reafon that many other motions are recipro- 

 cally exerted and relaxed ; for during the time of 

 exertion the ftimulus, or fenfation, which caufed 

 this exertion, is not perceived : but begins to be 

 perceived again, as foon as the exertion ceafes, 

 and is fome time in again producing its effect. As 

 explained in Seel. XXXiV. on Volition, where it 

 is (hewn, that the contractions of the fibres, and 

 the fenfation of pain, which pccafioned that exer- 

 tion, cannot exift at the fame time. The exertion 



ceafes 



