It might be better to read 'Thou, wouldest,' and 'Art,' to accord with the rest of the speech.
Act II.
Sc. 3.
"Threw many a northern look, to see his father
Bring up his powers, but he did long in vain."
I suspect that the poet wrote look, not 'long.'
Sc. 4.
"Feel, masters, how I shake."