RJS Page Object

I am struggling to understand and find resource to learn what parameter,
if that is the right word, can be inside the brackets in the page
statement for visual effect, i.e.

page["comment_#{@comment.id}"].visual_effect :shake,
          :duration => 6.5

From what I have seen through web searches it has to do with partials.
Is that correct? I got an typeerror (is null) trying to do this because
I don't have a partial:

page["#{@user.name}"].visual_effect :shake :duration => 6.5

Please help me understand this or refer me to a resource that makes it
clear to me. Thanks.

Hi Kevin,