Up for sale we have a deep cobalt blue Little Duchess marked oil lamp with brass saucer base with finger hold.  Lamp is held to the base with original brass spring. Has a newer chimney. Lamp measures 6 3/4" H to top of chimney. Manufactured in the 1870's. Burner is marked on the wick riser knob. "Made in USA.  Acorn".It's a sweet little lamp.