This is Thetis Dipping the Infant Achilles into the Waters of the Styx, by Donato Creti.  It measures 6 1/2" high by 10 4/5" wide.

I like the drawing style that hints at forms rather than depicting them with painful detail, although Creti did do a detailed painting of the scene.

This was done with brown ink and a fine tip caligraphy pen where I dipped the tip into the bottle of brown ink.  I never did this type of thing before and was scared of what might flow from the pen tip with each stroke.  A misstep would have spelled disaster.

I was not completely unhappy with the result and may try to emulate the style on some original work.

Donato Creti lived from 1671 through 1749.