It's been a long time since I read his book, but I don't think the Robertsons used plain seawater. Rather, I believe that some of their freshwater was partially contaminated with seawater and residue from the rubber sheet that they were using to catch rainwater. That is what they used via enema. It was so diluted that it posed no danger. It's a great book. I guess I'll have to get it and read it again. <img src="/images/graemlins/smile.gif" alt="" />

Regards, Vince