What does this sentence mean?

The avidness with which merchants and landowners in early-nineteenth-century Maryland and Virginia sought Joshua Johnston’s professional services attests to his artistic skill as a portrait painter.

What does this sentence mean? What does the “which” indicate here?

.
Which refers to avidness.

Merchants & landowners eagerly wanted Johnston’s paintings, so he must have been a good painter.
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It’s still kind of confusing to me.

Hi Cooliegirly,

Let me try and explain this:

The avidness with which merchants and landowners in early-nineteenth-century Maryland and Virginia sought Joshua Johnston’s professional services attests to his artistic skill as a portrait painter. What does this sentence mean? What does the “which” indicate here?

In the early nineteenth century merchants and landowners from Maryland and Virginia wanted to use J J’s professional services. The fact that (because) they tried to get these services with so much enthusiasm/determination (avidness) proves (attests to) that he was a very skilful (clever) painter.

Hope this helps.

Alan

Ah…Thank you! And thank you, too, Mr Micawber.