<html> <head> <style></style></head> <body class='hmmessage'><div dir='ltr'> <br>In response to Gary Henderson's question:<br><div><div dir="ltr"><br>In the past, gazers and rangers used "markers" to infer nighttime eruptions of various geysers such as Fan & Mortar, Penta, and Rift.  Markers usually consisted of little piles of gravel or pine needles in strategic locations that would not be washed away except by an eruption of the geyser.  This practice is not done anymore; when people talk about signs of an eruption now, they generally mean that they either saw or did not see physical evidence of a recent eruption.  Examples would be melted snow or ice, obvious wash marks in gravel, dead or matted grass, lack of pine needles in the area, etc.  One exception is at Giant, where the "GIANT GEYSER" name sign will roll forward off the platform and sometimes be carried down the runoff channel by a major eruption.<br><br>--Tara Cross<br>fanandmortar@hotmail.com<br> </div></div> </div></body> </html>