Geoscience Reference
In-Depth Information
supply an abundance to rivers since it only dampens the surface soil? The greater part of rain is carried
off to sea through river-beds. The amount which the earth absorbs is scanty, and the earth does not
retain that. For the ground is either dry and uses up what is poured into it or it is saturated and will pour
off any excess that has fallen into it. For this reason rivers do not rise with the first rainfall because the
thirsty ground absorbs all the water.
What about the fact that some rivers burst out of rocks and mountains? What will rains contribute to
these rivers, rains which pour down over bare rock and have no ground in which to settle? Besides, in
very dry localities wells are driven down to a depth beyond a distance of two hundred or three hundred
feet and find copious veins of water at a level where rainwater does not penetrate. So you know that
no water from the sky exists there nor any collection of moisture, but what is commonly called living
water. The theory that all water comes from rain is disproved by another argument: the fact that certain
springs well up on the high tops of mountains. It is obvious that they are forced up or are formed on
the spot, since all rainwater runs down.
Seneca apparently admits that most rainwater makes its way to river channels, but he feels
that this is a short-lived phenomenon and that these quantities are insufficient to maintain
a continuous river flow. He bases this argument on observations in his vineyards, which
are certainly perceptive, and similar to the findings of Perrault and de LaHire in the late
seventeenth century, as will be seen below.
In the later stages of the Roman era Judaic and Christian views gradually gained in
influence. In their writings the fathers, or early leaders, of the Christian church displayed a
broad knowledge both of biblical accounts and of classical philosophy. But in their eclec-
ticism among the different philosophical concepts they invariably accepted only those that
could be reconciled with the biblical narrative. The set of homilies
On the Hexaemeron
, i.e.
the six days (of creation), by Basileios of Cappadocia (
c
. 330-379 CE), is an example of
this. Basileios had been educated in the classical tradition at Caesarea, Constantinople and
Athens, and his writings generally reflect this background. In reference to Genesis (I,1,9)
and Ecclesiastes (1, 7), he (Basil, 1963; 4,3) wrote the following.
For this reason, according to the saying of Ecclesiastes 'All the rivers run into the sea, yet the sea doth
not overflow.' It is through the divine command that waters flow, and it is due to that first legislation,
'Let the waters be gathered into one place,' that the sea is enclosed within boundaries. Lest the flowing
water, spreading beyond the beds which hold it, always passing on and filling up one place after another,
should continuously flood all the lands, it was ordered to be gathered into one place.
Then, in (4, 6) he had this to say on the origin of rivers and springs.
In the first place, the water of the sea is the source of all the moisture of the earth. This water passing
through unseen minute openings, as is proved by the spongy and cavernous parts of the mainland into
which the swift sea flows in narrow channels, is received in the curved and sinuous paths and hurried
on by the wind which sets it into motion. Then, it breaks through the surface and is carried outside;
and, having eliminated its bitterness by percolation, it becomes drinkable.
Evidently, Basileios judged that among all available theories, the Hippon-Thales view was
the main one in harmony with the creation events in Genesis and with the water cycle
in Ecclesiastes. Similar views were promulgated some seventeen years later, around 389,
by Ambrosius (
c
. 333-397) in his own
Hexameron
, which was partly inspired by that of
Basileios. Ambrosius was then Bishop of Milan, but he had been converted to Christianity
only at the age of 41, and his early education had been in the classical Latin tradition of
the Roman upper class. His descriptions of the origin of rivers (Ambrose, 1961; 3, 2, 10; 3,
5, 22) are nearly the same as those of Basileios. The writings of Basileios and Ambrosius
show how the fundamental concept of natural philosophy, as Thales had initiated it, was
retained. Thus the Greek tradition of searching for an explanation of the physical world
within that same world, without animistic or direct divine intervention, was continued. But
