This 1880 child's mug is 3 1/2 in. tall and 3 in. on the top.  It's 2 1/2 in. on the bottom.  The line you see in the bottom is a shear mark.  I can't feel it on the bottom or inside the glass.  
There are two birds and an owl.  There is a tiny chip on the inside of the top of glass.

Bryce Brothers Bird on Branch