Spreading Seafloors - Four Revolutions in the Earth Sciences - page 116

face, yet it was not until 1963 that a Cambridge geologist, in a flash of insight, de-
ciphered the zebra stripes.
In 1962, the Cambridge University geophysicist Drummond Matthews
(1931-1997) was on a research cruise in the northwestern Indian Ocean, recording
magnetism and seismic velocities near the submarine Carlsberg Ridge, a branch of
the midoceanic ridge-rift chain that runs roughly north-south between Madagas-
car and India. When he returned to Cambridge, Matthews found assigned to him
a young graduate student named Fred Vine. He handed off to Vine the data from
the Carlsberg Ridge, asking him to produce a map that combined the magnetic and
gravity data with the submarine topography and departed on his honeymoon. “We
hadnoideaofconnectingseafloorspreadingandreversals—atleastIdidn't,”Mat-
thews recollected. 5
Vine had just heard a talk that Harry Hess of Princeton had given at Cambridge
in January 1962. Hess had been thinking about the geophysics of the ocean floors
and the mantle beneath for nearly thirty years. His first idea, that the granitic crust
underneath the oceans had been downbuckled into a deep fold, came a cropper
when scientists discovered that the oceanic crust contained no granite and, at only
five kilometers in thickness, was too thin to support the downfolding. Instead of
defending his original idea at all costs, Hess first amended and then replaced it
with a better one. This flexibility marked Hess's career, as he was that rare scient-
ist who could say, “I take pride in my past errors.” 6
Like nearly every other prominent American geologist, Hess had opposed con-
tinental drift. But he did not go out of his way to say so. As Frankel notes, this
meant that “when [Hess] became a mobilist in 1959, he had little baggage to jet-
tison.” 7 Hess's willingness not just to admit but to take pride in his mistakes is as
powerful a testament to Hess the scientist and Hess the man as his codiscovery of
the key process that led to plate tectonics. Without the ability to admit mistakes,
Hess would be remembered for being not only wrong but pig-headed to boot. One
who cannot admit that his favorite idea has turned out to be wrong is stuck defend-
ing that idea forever, watching from the sidelines as others move science forward.
An Essay in Geopoetry
Frankel pins down Hess's transition to mobilism almost to the day: no later than
July 6, 1959, evinced by a letter of that date from Hess in which he said that be-
cause of the paleomagnetic data, “It is becoming almost compelling to accept con-
tinental drift, something I never favored.”