4 42 DISEASES Class IV. 3. 3. 1. 



ORDO III. 



Retrograde AJfociate Motions. 



GENUS III. 



Catenated with Voluntary Motions,. 



SPECIES. 



1. Ruminatio. In the rumination of horned cattle the food is 

 brought up from the firft (lomach by the retrograde motions of 

 the ftomach and cefophagus, which are catenated with the vol- 

 untary motions of the abdominal mufcles. 



2. Vomitio voluntaria. Voluntary vomiting. Some human 

 fubjecls have been faid to have obtained this power of volunta- 

 ry action over the retrograde motions of the ftomach and cefoph- 

 ao-us, and thus to have been able to empty their ftomach at 

 pleafure. See Seel:. XXV. 6. This voluntary act of empty- 

 ing the ftomach is poflefled by fome birds, as the pigeon ; who 

 has an organ for fecreting milk in its ftomach, as Mr. Hunter 

 obferved ; and foftens the food for its young by previoufly fwal- 

 lowing it ; and afterwards putting its bill into theirs returns it 

 into their mouths. See Seel:. XXXIX. 4. 8. The pelicans ufe 

 a ftomach, or throat bag, for the purpofe of bringing the nth, 

 which they catch in the fea to fhore, and then eject them, and 

 eat them at their leifure. See Seel:. XVI. 11. And I am well 

 informed of a bitch, who having puppies in a (table at a diftance 

 from the houfe, fwallowed the flefti-meat, which was given her, 

 in large pieces, and carrying it immediately to her whelps, 

 brought it up out of her ftomach, and laid it down before them. 



3. Erittlatio voluntaria. Voluntary eructation. Some, who 

 have weak digeftions, and thence have frequently been induced 

 to eruct the quantity of air difcharged from the fermenting ali- 

 ment in their ftomachs, have gradually obtained a power of vol- 

 untary eructation, and have been able thus to bring up hogf- 

 heads of air from their ftomachs whenever they pleafed. This 

 great quantity of air is to be afcribed to the increafe of the fer- 

 mentation of the aliment by drawing off the gas as foon af it is 

 produced. See Sect. XXIII. 4. 



ORDO 



