, and which - restrictive/non-restrictive

1) Mr. Lovelace has seen divers apartments at Windsor; but not one, he says, that he thought fit for me, and which, at the same time, answered my description.
2) All the toys that infatuate men, and which they play for, are the self-same thing.
3) The hills were so broken and precipitous as to afford no passage except just upon the narrow line of the track which we occupied, and which was overhung with rocks, from which we might have been destroyed merely by rolling down stones.
<Source: 'And who'; 'and which' in The King’s English, 2nd ed by H.W. Fowler http://www.bartleby.com/116/206.html>

The book says in #1, "and which" has been used as restrictive use and in #2, "and which" has been used as non-restrictive.
I don't know why; please enlighten me.

Thank you in advance for your help.