Because the presence of teeth would interfere with their suckling, while the teeth would be of no service, until the child _could take food requiring mastication_. 1071. _Why cannot flesh-eating animals live upon vegetables?_ Because the gastric juice of a flesh-eating animal, being adapted to the duty which it has to perform, _will not dissolve vegetable matter_. 1072. _Why have birds gizzards?_ Because, having no teeth, the tough and fibrous gizzards are employed _to grind the food preparatory to digestion_. 1073. _Why are small particles of sand, stone, &c., found in the gizzards of birds?_ Because, by the presence of those rough particles, which become embedded in the substance of the gizzard, the food of the bird is more effectively ground. When our fowls are abundantly supplied with meat, they soon fill their craw, but it does not immediately pass thence into the gizzard; it always enters in small quantities, in proportion to the progress of trituration, in like manner, as in a mill, a receiver is fixed above the two large stones which serve for grinding the corn, which receiver, although the corn be put into it by bushels, allows the grain to dribble only in small quantities into the central hole in the upper mill-stone.--_Paley._ CHAPTER LIV. 1074. _Why has the mole hard and flat feet, armed with sharp nails?_ Because the animal is thereby enabled to _burrow in the earth_, in search for worms. Its feet are so many _shovels_. 1075. _Why is the mole's fur exceedingly glossy and smooth?_ Because its smoothness enables it to work under ground _without the soil sticking to its coat_, by which its progress would be impeded. From soils of all kinds, the little worker emerges shining and clean. [Verse: "I know all the fowls of the mountains, and the wild beasts are mine."--PSALM L.]