Any ideas? Historically, the Century family was used quite often as the typeface for plain text in music scores, so that might be a starting place, but I'm wondering if there's something different shown in this hand-engraved (into metal plates) copyright text. Thanks!

I think I may have answered my own question. I think this may be another instance of the Scotch family. It's close, but not identical (notice the different italic lower-case "g" than in the source image):

download at MyFonts

download at MyFonts

download at MyFonts

download at MyFonts

 

Not a perfect match either, but digital versions with a multi-storey italic g do exist as well. 

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Thanks, Ralf.