Swarms of visitors pass by the site of Link every day of open season without realizing a geyser of major proportions lurks there; indeed, most don't know there's a geyser there at all. Part of its obscurity is because the vent is hard to see; it's raised above the level of the paved trail at its crossing of the Firehole River near Riverside and Fan and Mortar Geysers, and can be seen well only from the south. A larger factor, however, is that its major eruptions are rare. The most recent major reported to geysertimes.org or to GOSA was in 2012. Majors leave clear signs of their occurrence, so it is very unlikely that any since then have been missed. Even minors, described by Bryan (TGoY) as "very common," are rarely reported, although some of these certainly go unnoticed or unrecorded.
Link has a complex history well described in Bryan's book. In most years when it has major eruptions (including the most recent activity in 2012), majors appear to be isolated events that may not be repeated for years, as in the current lull. In other years entire series of majors occur. According to Bryan, Link's busiest known year for majors was 1983, when 40 majors occurred from October 13 to 18. Other years with series of majors included 1957, 1958 and 1974. Majors can reach heights approaching 100 feet as in the powerful 1974 eruptions, and enough water is discharged to muddy the Firehole for some time. Some of the more recent events, however, were considerably less powerful.
Minors are clearly more frequent, although current, quantitative information on their frequency is hard to come by. Bryan reports minor intervals of 1 to 4 hours and durations of 15 to 30 minutes, with "superheated boiling that domes the water 3 to 4 feet high." Reports of minors rarely reach geysertimes.org or GOSA correspondents, so it is unclear whether these intervals remain as they were at the 2009 publication of Bryan's book. Many Link minors, however, are "noticed" without being "seen." With the (comparatively) frequent activity of Fan and Mortar Geyser(s) in recent years, it's common for runoff from a Link minor to be noticed by gazers sitting patiently at the Fan and Mortar benches. Information on intervals based on these observations does not seem to be available.
|Good question! Even Bryan notes only that major eruptions "probably" begin during minors; certainly during the powerful eruptions of August 8, 1974, play began with "a doming of water" within the crater. With this lack of certainty, the observer who sees a minor from a viewpoint to the south, or runoff while conducting a Fan and Mortar sit, might want to keep an eye on Link's vent. The minor eruption probably won't develop into a major, but then again, it might ...