Pompey Brenton, 1772
Newport Common Burying Ground
carved by John Stevens III
This stone was carved right around the time when John Stevens III started carving in a "typographic" style rather than a "lyric" style (this terminology c/o John Benson at the John Stevens shop). The change was, apparently, related to the arrival of Baskerville type in Newport. According to Mr. Benson, the typeface became wildly popular and captured the attention of John Stevens III, who abandoned the letterforms of his youth in favor of the more regular, ruled letterforms of his post-1772 stones.
I'm not entirely sure I can reliably describe the differences — certainly, I cannot approach Mr. Benson's enthusiasm for the subject — but I can provide an example.
In the Samuel Petteface stone (1771), also carved by John Stevens III, the numeral 1 is very different from the typographic 1 on the Pompey Brenton stone. Mr. Benson also assures me that there is a greater harmony of form between the letters and iconography on the Petteface stone than on the Brenton stone, though my eye is not as discerning on this point.