TASTE OF GRANIVOROUS BIRDS. 119 



and aptly describes it as an organ " wherein the meat, 

 as in a mill, is ground to pieces, and then pressed by 

 degrees into the guts in the form of a pulp ; for 

 which purpose the deductor serves to deliver the 

 meat from the echinus to the laboratory, as a hopper 

 to a mill ; the four grinders, or chief operators, are 

 the millstones*." 



Agreeably to these views, it has been recorded 

 that Felix Plater found an onyx, a precious stone of 

 peculiar hardness, which had been swallowed by a 

 hen, diminished no less than one-fourth of its bulk 

 in four days ; and a French gold piece of money lost 

 in the same way sixteen grains of its weightt. 

 Reaumur and Spallanzani, again, found that when 

 tin tubes full of grain were introduced into the sto- 

 machs of turkeys, and allowed to continue there a 

 considerable time, they were broken, crushed, or 

 distorted in a most singular manner. " I have seen," 

 says Spallanzani, " instances without number of such 

 contusions, one of which I cannot forbear here relat- 

 ing. Having found that the tin tubes which I used 

 for common fowls were incapable of resisting the 

 stomach of turkeys, and not happening at that time 

 to be provided with any tin plate of greater thickness, 

 I tried to strengthen them by soldering to the ends 

 two circular plates of the same metal, perforated only 

 with a few holes for the admission of the gastric fluid. 

 But this contrivance was ineffectual ; for after the 

 tubes had been twenty hours in the stomach of a 

 turkey, the circular plates were driven in, and some 

 of the tubes were broken, some compressed, and 

 some distorted in the most irregular manner. 



" I then tried the following means of preventing 



this inconvenience. Having perforated the circular 



plates in the centres, I passed a wire through the 



* Comp. Anat. of the Stomach, ix. 40-1. 



f Swammerdam, Biblia Natures, p. 163. 



M3 



