58 | Great Geologists
Dana’s sketch of an erupting Vesuvius, published in 1834.
After completing his studies at Yale in 1833, Dana served as a
mathematics instructor on a U.S. Navy ship that sailed to the
Mediterranean. There, he saw Mount Vesuvius in eruption and
sent a report back to Silliman. This report would form the basis for
the first paper published by Dana in 1834. In this same year, Dana
returned to Yale to take up teaching and research duties. His first
objective was mineralogy.
Silliman had an extensive collection of minerals which Dana could
supplement with his own specimens, some collected when
a child. Using this material, Dana set about developing a new
mineral classification based on chemistry and crystallography. His
results were published as System of Mineralogy when he was
just 24. This remarkable work has formed the basis of modern
mineralogical studies ever since.
Reminiscent of the opportunity afforded to Charles Darwin to sail
on the Beagle, in 1838 Dana was offered the opportunity to serve
as the geologist and mineralogist of the U.S. Exploring Expedition
(1838–1842). For American science, this expedition was without
precedent. A fleet of six ships was charged with charting islands
in the Pacific, exploring the South American coast and even
venturing towards Antarctica. The expedition was substantially
funded by the U.S. Navy; and in addition to Dana, there were
specialists in botany, vertebrate and invertebrate zoology and
philology on board, plus two artists.
For Dana, the voyage was not always comfortable (“naval
servitude” as he remarked in a letter). The expedition captain
had a volatile temperament, and there were the hazards of any
voyage in difficult waters. Dana’s ship was almost lost in the
Straits of Magellan, and aggressive natives made work difficult in
Fiji. Nonetheless, he explored the Andes, the atolls of the Pacific
and the active volcanoes in Hawaii. Thus, the expedition gave
Dana the chance to experience geology on a global scale, which
impacted his geological thinking for the rest of his life.
On his return to Yale, Dana’s observations were summarised