paper.js how to set up multiple canvases using only javascript

I haven't worked with Paper.js extensively, but it seems that each call to Path isn't using the PaperScope from which it's being accessed, but the global paper object. So if you overwrite paper to your desired PaperScope before each instantiation it should work.

See my updated fiddle.

I actually solve this a bit differently:

var scope1 = new paper.PaperScope();
var scope2 = new paper.PaperScope();

When I want to draw in scope1:

scope1.activate();
// now I draw

Similarly when I want to draw in scope 2

scope2.activate();
// now I draw