[plt-scheme] image-snip initialization

(define Image-Snip%
   (class* image-snip% ()
     (super-instantiate ())))

(define Image (new Image-Snip%
                      (filename "/Users/dr/test.jpg")
                      (kind 'jpeg)
                      (relative-path? #f)
                      (inline? #t)))


This fails, but I really don't understand how or why.

Why are some classes instantiated with 'new' while others are created 
with 'make-object'?  What are the rules for this?

- dr