1. How do the Dwarves keep water from coming down their light-shafts?
I'll go with those who propose some sort of water catching device at the end of
the shaft.
2. For that matter, how do they arrainge drainage throughout the whole of
Moria?
I don't think the dwarves' deepest shafts were above the water table or
above ground level -- which would leave the shafts dry or easily drainable ,
respectively. Therefore, I have to conclude that the
dwarves possessed steam engines or the Middle-earth equivalent.
Before the steam engine, mines were pumped out by various methods (see
excerpt below) but none of them worked well enough beyond a depth of
about 100 meters or so. It was apparently only the invention of the steam
engine driven pump that allowed water to be pumped out from greater
depths. One could speculate that the dwarves must have possessed some sort of
technology equivalent to a steam engine in order to truly plumb the
depths.
Excerpt from the following: http://www.history.rochester.edu/steam/lord/2-3.htm
The development of drainage in the tin-mines is important, as it is
the immediate cause of the commercial success of the steam-engine which, in its
turn, is the central fact of eighteenth century history.
In the earliest gravel or stream works the water was carried out in wooden
bowls, or was carried off from the working in a " level " or trench leading
from the work to the river. Later came the windlass turned by man-power, then
small hand or force pumps, contemporary with which in the larger works was the
adit. The adit was similar to the level only driven through the hill-side to
meet the shaft at its foot. This last was expensive and temporary, because as
soon as the shaft was driven deeper additional apparatus had to be used to
raise the drainage to the level of the adit. Various mechanical pumping devices
worked by man-power were also tried, but the severity of labour they entailed
on the men working them15 made them unsatisfactory and costly. Water wheels
were used in some mines, but as their power was limited a deep mine needed two
or three wheels one above the other to clear it effectively. In place of these
combinations of wheels, John Costar, in 171O, successfully used a single large
water-wheel to drain some of the deeper mines. His invention, however, was
quite overshadowed by that of the steamengine.16 .......
The first working steam-engine was constructed in Devonshire by Thomas Savery.
He was a clever engineer, and among other discoveries he made a paddle boat to
move without wind. ... He made a steam-engine in which the steam was
alternately condensed in two vessels, causing a vacuum into which the water
from the pit was actually sucked, thus avoiding any pumping apparatus.
See also
http://inventors.about.com/library/inventors/blsteamengine.htm and
http://www.egr.msu.edu/~lira/supp/steam/
The second reference includes a nice picture of how it works.
2. 2/3 sounds reasonable to me. Maybe Gandalf wasn't very comfortable
where he was seated.
3. Sounds good to me.
4. I like the secret door idea.
5. Stone seems like a perfectly reasonable material to me. I wonder if
the bridge was a natural arch that the dwarves shaped for their own purposes.
CHALLENGE
As the Dwarves hollowed out these truly vast works extending for miles under
three mountains, what did they do with the tailings?
Hmmm, I suppose I thought of Moria as consisting of some natural caverns
(reworked of course) as well as "dug" passages. That would
cut down on the amount of tailings. Perhaps they threw a bunch of
them into the "bottomless" abyss below the bridge
?
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We who still labour by the cromlech on the shore,
The grey cairn on the hill, when day sinks drowned in dew,
Being weary of the world's empires, bow down to you,
Master of the still stars and the flaming door. --W.B. Yeats
