There is, alas, no whatsoever trace of an artist named H. M. Tudor in
any of the art encyclopedias and many reference books I consulted, so
his identity will unfortunately remain a mystery.
However, I was successful when searching for information about Joseph
Grozer. This is what I found out:
Joseph Grozer (1755-1799) was an English engraver. According to his
signed prints, he was located in London and active between 1784 and
1797. He did a number of excellent copper and mezzotint engravings
reproducing paintings by Sir Joshua Reynolds (1723-1792), George
Romney (1734?1802), George Moreland (1763-1804) and others. Of his
mezzotint engravings listed in Chaloner Smith's 'British Mezzotinto
Portraits', the best works are 'Master Braddyll' (dated 1786) and
'Hon. Frances Harris' after paintings by Reynolds. Also noteworthy is
a print dated 1796, titled 'First Interview of the Prince and Princess
of Wales' after J. Graham. One of his few stipple engravings is 'Lady
St. Asaph' (1792), after Reynolds, whose 'Age of Innocence' he also
reproduced in crayon manner.
In case you'd like to see more of Grozer's work, you can view several
engravings of portraits by him on the website of the British National
I hope that this information will be of use for you.
Allgemeines Lexikon der bildenden Künstler, Vol. 15. Verlag von E. A.
Seemann, Leipzig, 1922.
Fine Arts Museum of San Francisco: Joseph Grozer