/* 

The first time we visit this catalogue, we write a cookie that contains
the location of the catalogue, relative to the shared files.

This is used for two purposes. 1) to allow the shared files to load the
catalogue-specific file HEAD.PHP, and 2) to allow the pages to produce an
error message if their URL is typed directly into the address bar.

We need to use a cookie, rather than passing POST variables, because 
it gets tedious passing POST variables to the external payment sites,
and then picking them up again afterwards - especially if we cannot run
an 'include' file because $location is not set to allow us to see where
it should be included from!

*/
  
document.cookie = "location=../he10/; path=/" ;