Set of 4 Boston & Sandwich Glass Co. Blown Glass Copper Wheel Engraved Salts.  They measure between 2 - 2 1/4" across and 1" high.  They are handblown and thick, varying in size slightly.   The engraving is so small, yet so masterfully done.  The detail is amazing, and there is an "S" monogram as well.  Purchased from Cape Cod, MA where the factory was located over a century ago.  They are all in excellent condition with no chips or cracks.