134 FACULTIES OP BIRDS. 



have remained some time in the stomach, are not 

 smooth or shining, as they would be if worn by the 

 friction of the coats ; but are rough, furrowed, or 

 perforated, presenting precisely such an appearance 

 as would be produced by the corrosion of a solvent. 



This solvent reduces the hardest and the softest 

 bodies alike to impalpable molecules, which may be 

 observed by the microscope, and even by the naked eye. 

 Vallisnieri found in the stomach of the ostrich a nail 

 fixed in one of the sides, in such a manner as to pre- 

 vent its meeting the opposite side, and consequently 

 the compression of the contents ; yet the food was 

 as completely dissolved in this ventricle as in another 

 in which the usual action took place, and *his at 

 least proves that the digestion is riot performed solely 

 by trituration. He observed a copper thimble in the 

 stomach of a capon, which was corroded only where 

 it touched the gizzard, and consequently where it was 

 least exposed to the attrition of the hard substances ; 

 whence the solution of metals in the gallinaceous 

 tribe must be ascribed rather to the action of some 

 menstruum, than to the pressure and resistance of the 

 coats, and the analogy naturally extends to the ostrich. 

 He discovered in the stomach of an ostrich a piece 

 of money, which had been so completely corroded that 

 its weight was reduced to three grains*. 



We have remarked, that the fruit-eating birds seem 

 indifferent to the comminution of their food before 

 it is swallowed. The black-cap and the fauvette 

 (Philomela horlensis) will accordingly swallow berries 

 of so large a size, that it might previously appear 

 impossible for their little gullets to admit them. In 

 the case of very ripe grapes or cherries, we can 

 better comprehend this from the ready compressibility 

 of the fruit ; but the hard, incompressible berries of 

 the ivy are apparently swallowed with equal ease and 

 * Notomia deilo Struzzo, 4to, Padova, 1626, 



