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cale. Another had measured the seafloor magnetic anomalies. A third had deve-
loped the theory of seafloor spreading. Yet their results came together beautifully.
For those who had denied drift and seafloor spreading, the horns of the dilemma
had become uncomfortably sharp.
TwootherstudiesfromLamontraisedtheoddsagainstcoincidenceevenfurther.
During the fall of 1965, the National Science Foundation vessel
Eltanin
sailed
above the East Pacific Rise, the broader, lower analogue of the Mid-Atlantic Ridge
at 50 degrees south latitude. Although the Vine-Matthews paper had been out for
more than two years, astoundingly, “none of us was aware of the hypothesis at the
time,” remembered one of the scientists aboard the
Eltanin
that fall.
16
The main purpose of the cruise was to record seismic measurements, but the
scientists decided to gather magnetic data as well. It fell to the graduate student
Walter Pitman to plot the magnetic intensities. He had shown the magnetic profile
from an earlier
Eltanin
log to his Lamont colleagues, pointing out that it looked
“almost exactly the same as the [Vine-Matthews] profile over the Juan de Fuca
ridge,” which had come out a few months before. At least one of these colleagues
must have known of the Vine-Matthews hypothesis, for he said to Pitman, “Ha!
Ha! I suppose you're going to prove Vine and Matthews are right” (333).
As Pitman continued his analysis of the
Eltanin
data, he saw in the emerging
magnetic profile the same amazing symmetry that Vine and Wilson had observed:
the highs and lows of magnetic intensity on one side of the rise precisely matched
those on the other, even to the slightest squiggle. Pitman showed the profile to his
supervisor,JamesHeirtzler,whorespondedthatitwas“tooperfect”tofittheVine-
Matthews hypothesis. Joe Worzel, a longtime Lamonter and dedicated fixist, said
after examining the profile, “Well, that knocks seafloor spreading into a cocked
hat. Its too perfect” (335).
The second confirmation of the Vine-Matthews hypothesis came from an unex-
pected source: sediment cores from the seafloor that at Maurice Ewing's instruc-
tion Lamont scientists hadcollected. Asthe techniques ofpaleomagnetism hadim-
proved, it had become possible to measure the direction even of the weak mag-
netism in sediments. Neil Opdyke, one of the few Lamonters open to continental
drift, knowing that paleomagnetic directions were easier to determine at high latit-
udes, used an ultrasensitive magnetometer on a set of sediment cores from the far
South Atlantic. He located in the cores each of the magnetic epochs and events of
the latest paleomagnetic timescale. In the autumn of 1965 he found a new, short-
lived reversal at 0.9 million years but was unsure whether it was real. At the spring
1966 meeting of the American Geophysical Union, Opdyke was more confident.
In a hotel-room discussion, he told Dalrymple of the new event, only to hear him
