I originally worked from the photograph on page 980 of Volume 4 of American Antiques of the Israel Sack collection. I also used a similar example in a 1988 C.L.Prickett catalog to study details. Both were attributed to Benjamin Frothingham of Charlestown, Massachusetts. I arrived at these dimensions by scaling from the photographs and using the dimensions provided as maximum dimensions. I made the blocking slightly under 11/16", thinking 3/4" a bit too heavy.