What's the name for the pen and ink drawing style seen in J. J. Grandville's art?
The kind of shading with many thin lines is called hatching.

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It's very common in ink or pen drawings and printing techniques like etching or woodblock printing. A sub-category of prints with especially fine details is the &quot;old master print&quot;.
This site demonstrates a number of different hatching techniques and how they influence our perception of the shapes