From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.tech
Subject: Re: Tire question for Jobst
Date: 14 Jun 1999 17:54:53 GMT

Brian Nystrom writes:

> Thanks for the feedback. BTW, so I understand what others are
> talking about, can you describe a cattle guard or point me to a
> picture of one somewhere?

Most animals have a small footprint in comparison to humans and many
have hard hooves that give poor traction for standing on narrow slats.
Cattle in particular are often fenced on rangeland traversed by public
roads that cannot have gates.  Instead of gates cattle guards over
which wheeled vehicles can travel but cows cannot are used.  Such a
barrier typically employs a five to six foot wide shallow pit covered
by railway rails, transverse to the road, spaced four to six inches
apart.  A cow trying to cross this would break a leg.  Deer have no
problem because they jump over the fence although they, like cows
cannot cross a cattle guard.  These animals all recognize the hazard
and regard it as impassable.  However, cats and most dogs have no
problem walking over them.

On some highways, the appearance of a cattle guard is painted on the
road.  I have seen these but never seen livestock nearby to assess
whether they are fooled by the ruse.

Jobst Brandt      <jbrandt@hpl.hp.com>

From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.tech
Subject: Re: Tire question for Jobst
Date: 18 Jun 1999 21:08:14 GMT

Woodelf (who?) writes:

>> Crikies, how deep is the ditch? The cows around here would just
>> step between the rails if it isn't any deeper than a foot or less.

> Their feet don't actually fit between the slats, generally.

They fit and do so grotesquely, breaking a leg.  Even if the hoof were
six inches in diameter, (the spacing of rails) balancing it on a steel
pipe or RR rail is not a possibility for the cow.  I notice that
hypothesizing about this from the KBD is still as popular as ever...
actually.  Reality is different.

> My understanding is it's more of a psychological than a physical
> barrier.  (Cows have some interesting hangups; I once read a book by
> a semi-autistic engineer who'd solved all sorts of long-standing
> problems dealing with cattle by trying to address their psychology.)

Oh, I suppose you believe that this gives your assessment of cattle
guards great credibility.  What did this book have to say about cattle
guards, or did it mention them?

Jobst Brandt      <jbrandt@hpl.hp.com>