Let it not be said that Edmund Morris' new Ronald Reagan biography "Dutch" has failed to dig up heretofore undisclosed details about the man's life. Why, on the back cover alone, we learn that "dentists even praise the clarity of his saliva." The clarity of his saliva?

"I have no idea what the hell that means," says Richard Price, a dentist in Newton, Mass., and a spokesman for the American Dental Association.

Price personally has never given deep thought to the former head of state's salivary clarity. However, when pressed, he did admit that there are qualitative differences in patients' oral secretions -- but none that would that would either make or break a presidential election. "Some people have a very thick, a very mucousy, saliva. Ropey would be the technical term. The good stuff, if you will, is a copious flow of nice clear saliva, almost waterlike."

And what's so unpraiseworthy about ropey spit? (I'm not being crude here. Price says he's read that spit is the proper term for saliva that's been polluted by bacteria. Only the freshly secreted stuff gets to call itself saliva.) The downside of ropey spit is that it isn't very effective at flushing away bacteria and bacterial "breakdown products," the latter being perpetrators of tooth decay and bad breath.

Still, saliva clarity is not something dentists routinely remark upon. "We would never say, 'Why Mrs. Jones, you have a nice, clear saliva today,'" says San Francisco dentist Mat Kiisk. Price agrees. He says that never, in his 30-some years of dentistry, has he heard colleagues sitting around remarking upon the qualities of someone's saliva, least of all Ronald Reagan's. "How would we even know? He would have to have, like, spittle on the side of his mouth. Or drool." Don't go there, Richard.