Underground Rivers - University of New Mexico

Chapter 12 -- Superterranean Metrics
In the leftmost piece, a product of the Middle Ages, God is measuring his creation, the units
perhaps being metrics of holiness. In the next painting, 500 years later, God again reaches
downward, but this time to measure the tangible. In the third, fueling the science vs. religion
controversies to come, God is replaced by Newton.
Newton’s Principia (1687) was elegant as it pertained to celestial workings, but provided little but
a few conceptual pointers regarding much of what occurs below. The path of Mars made more
mathematical sense than did the level of the Thames.
A 1692 issue of The Gentleman’s Journal listed ten different explanations of the oceanic tides,
complaining that competing ideas caused “the learned ... [to be] much puzzled about... the Flux
and Reflux of the Sea.”
The task of quantifying subsurface flow was indeed the most challenging part of the hydrologic
cycle. Rainfall could be measured with a pan. Streamflow would be estimated by measuring a
cross-section and timing a floating object. But no one could reach into the earth with a pan, a
ruler, a clock, or for that matter, any instrument of measurement.
As we remarked in concluding Chapter 2, we'd like someone underground to take a look, but if
we can't send someone with a lantern, perhaps we can measure what's occurring on the earth's
surface and deduce the rest.
This chapter explores how measurement disproved the hydrologic necessity of underground
rivers.
We'll begin by looking three Frenchmen,
Bernard Palissy,
Pierre Perrault and
Edmé Mariotte,
and then cross the channel to note the contributions of three Englishmen,
Edmond Halley,
Charles Hutton and
John Dalton.
Three Frenchmen
French Huguenot Bernard Palissy (1509-1590) began
his career making stained glass windows and after 16
years of experimentation, perfected an enameled pottery
which brought him and his heirs great fortune. An 1880
Palissy factory gravy dish is shown to the left.
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