Yep, I (Joe) thought they were one and the same, a magnifying glass and a diminishing glass. They are not. I feel a little diminished, but appreciate learning something new. A diminishing glass has a concave lens that reduces an image and has been a tool for artists such as Thomas Hart Benton in assessing large subjects. Please note that on page 54 of our book, Harzfeld's: A Brief History, the fourth paragraph, second sentence should read: "He would continually step back to look at the work through a diminishing glass."
Also, the first sentence in Chapter 5 on page 53 should start "In the fall of 1946," rather than "In 1947,". The mural was completed in 1947, however the commission would have been in 1946.
We appreciate the friend who alerted us to this and welcome your emails on inaccuracies in our book.
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