What does "this" mean in this sentence? [closed]

English poet Robert Browning in his poem "Paracelsus" has written:

"Nay, autumn wins you best by this its mute appeal to sympathy for its decay"

[AllPoetry]

Why is "its" preceded by "this"? If I parse it as if there is no "this" it makes total sense, but that just doesn't seem correct. However, the original sentence also doesn't seem grammatically correct to me. So why was "this" used in this context and what was it supposed to mean?

My best guess is that there should be a long dash after "this":

"Autumn wins you best by this — it's mute appeal...",

but no source I could find gives this line with dash. Besides, English punctuation differs significantly from punctuation in my native language (Ukrainian), so my grammar sense might be tricking me.

Solution 1:

'Its mute appeal to sympathy' specifies what 'this' refers to. It's an obsolete usage. Another example that springs to mind is in the story of the Prodigal Son (Luke 15:24 in the King James Bible) - 'For this my son was dead, and is alive again.'