I have several old engravings by Charles Green, Francois Lameng etc. All have what appears to be original little drawings of the Artistist portrait himself in the lower portion of the engraving and additional little drawings on the other side of the engraving. These are both on the engraving and not the matting. I have seen other engravings but without these drawings. Can someone tell me what these are?

Also I have a few engravings that are on tissue type paper not hard stock. What are these?

Hope some one can help me-----Thanks.