NH Zamboni: A log book is a required item in a physical cache per the section of the requirements located here:
http://www.geocaching.com/about/guidelines.aspx#guide
Please note the sentence "For all physical caches, there must be a logbook, scroll or other type of log for geocachers to record their visit."
Finding a magnet does not qualify. The cache page has been archived.
-Zamboni
Groundspeak volunteer reviewer for NH / VT