A roar went up from the large crowd when another burst started. There are "geyser gazers" that are regulars (I think they record data such as eruption lengths, heights, and bursts for the rangers to help with prediction times) and I overheard one of them saying it was one of the best eruptions they've seen of Grand Geyser (although with this impressive geyser I can't imagine there ever being a dull eruption!).