Re: Horses vs Coaches

Ric Locke wrote:

On Fri, 23 Nov 2007 13:53:03 +0000, Catja Pafort wrote:

Ric Locke wrote:

The prevailing theory for centuries was that a wheel should be narrow,
so that it would sink until it hit something solid and be thin enough to
pull through the muck. A modern engineer, faced with designing a coach
from scratch, would go the other way -- try to find light enough
materials to make the wheel extremely wide, so that it "floated" on the
surface rather than digging or sinking in. The resulting coach would
look very strange to us, but it would be much less likely to get mired
and would be enormously less damaging to the road and more tolerant of
bad road conditions. The knock-on effects are left as an exercise for
the student.

Only works if you have the material. If all you have to work with is
wood, then you're faced with something very heavy that offers a lot of
resistance.

And I don't think you _can_ make surfaces wide enough that they don't
dig into heavy soils, regardless of the materials. 4WD vehicles with
their comparatively wide wheels will still dig deep ruts into muddy
lanes.

Heh. Google "rolligon". Not that a preindustrial culture could build
one, mind you, but there are ways to avoid the problem. Perhaps
something like a barrel...

The manufacturer tells me nothing about how much force you need to get
the thing moving, which will be critical. If you're looking at a
carriage moving on a fairly even and firm surface, it needs very little
power to keep moving once it's in motion; and I feel that will be
important if your only mode of propulsion is horses.

Plus, a barrel-type construction won't withstand the forces a wheel has
to cope with. With steel and rubber you can create such items; but until
then, you'll probably find that the wheel will be the most efficient
mode.

If you have the engineers to do it, I'd suggest levelling the terrain
and putting loads on rails; much easier to shift loads that way, you
need less horsepower.

And make the wagons run on time?

Weeeelllll...


Catja


--
writing blog @ http://beyond-elechan.livejournal.com
.

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