It looks like someone made a plexiglas coffin cover because the original was missing. It is probable in the 1880's or 90's. We have an 1852 Grover and Baker treadle with a coffin lid but it is made of Walnut. Encyclopedia of Antique sewing machines lists ours valued between $500 and $1,200. It is nice but I would love to have it with the original lid.