Tim, I don't know what has been said by others, but you might borrow one of those inexpensive infrared thermometers and find where the temp changes on the hull. I do it to find the level of heating oil in my tank, but have not tried it myself on less conductive fiberglass. Tom Jenkins M17 Scintilla -----Original Message----- From: montgomery_boats-bounces@mailman.xmission.com [mailto:montgomery_boats-bounces@mailman.xmission.com] On Behalf Of Tim Diebert Sent: Wednesday, June 18, 2008 5:29 AM To: 'For and about Montgomery Sailboats' Subject: M_Boats: Level Reference I know it was asked but did not see a reply. Is there an area of the 17 hull that is a known level reference relative to water line? I don't always read all the emails......so if anyone got this one some help would be grand. Tim and PUFF _______________________________________________ http://mailman.xmission.com/cgi-bin/mailman/listinfo/montgomery_boats