xpaths.rb

# Explicit path from root of document
elements = doc.xpath("/html"\
                     "/body"\
                     "/div[@id='m1']"\
                     "/div[@class='middle']"\
                     "/div[@class='col1']"\
                     "/div[@class='box1l']"\
                     "/table[@class='cat']"\
                     "/tr[td/a/img[@src='/i/ple1.gif'] and td/a[contains(@href,'Canon-EF-lenses')]]")
                     
# Selects nodes in the document from the current node that match the selection no matter where they are
elements = doc.xpath("//tr[td/a/img[@src='/i/ple1.gif'] and td/a[contains(@href,'Canon-EF-lenses')]]")