Hi David, Thanks for link -- very interesting and encouraging. What I missed though was any mention of water as the consummate heat storage mechanism. Jim -----Original Message----- From: pbs <pbs@pilling.demon.co.uk> To: Pacific Bulb Society <pbs@lists.ibiblio.org> Sent: Thu, Jun 7, 2012 9:43 pm Subject: Re: [pbs] New book jmsjon664@aol.com wrote: > I hope that helps, and I'll be interested in further thoughts. There was a discussion here: http://www.srgc.net/forum/index.php?topic=6382.35 which discussed keeping greenhouses warm in Winter. Diane contributed to it. David Pilling