Re: (rshsdepot) Tunnel: 'Hidden historical asset of Baltimore'

["Jim Dent" <james.dent_@_itochu.com>]

Bruce,

-From my limited knowledge of the Baltimore area and from perusing the USGS
maps at:
http://www.topozone.com/map.asp?lat=39.316481995840355&lon=-76.6101768898642
5&s=25&size=m&symshow=n

it would appear that the Howard St. Tunnel does not travel under any bodis
of water, instead it carries the tracks from the north side of Baltimore
south towards Camden Station.  For the most part the tunnel is underneath
the north-south running Howard St.

Jim

- ----- Original Message -----
From: "Bruce Mowbray" <TRAINHEAD_@_mymail.emcyber.com>
To: <rshsdepot_@_lists.railfan.net>
Sent: Thursday, August 02, 2001 10:14 AM
Subject: Re: (rshsdepot) Tunnel: 'Hidden historical asset of Baltimore'


> At 09:18 PM 8/2/01 -0400, you wrote:
> >While I am not sure about the 4.8% grade to the Howard St. Tunnel, Saluda
> >Grade in NC has a sustained grades of 4.5% and short stretches that
exceed
> >5%.
> >
>
> Maybe I am going out on a limb here but,
>
> If the area or the stiff grade is not too long and knowing the tunnel is
> under a river, I would imagine there is an opposing grade toward each end
> of the tunnel with the bottom of the grade at the center. Here is what I
> think could be the allowance for such a steep grade. The train enters the
> tunnel and heads down grade. The rest of the train follows. The leading
> part of the train reaches the bottom of the grade and heads upgrade to the
> other end of the tunnel. The rest of the train is still heading down grade
> and this helps to push the leading end of the train upgrade. As long as
the
> train isn't short, the opposing grades could effectivly cancel each other
out.
>  Just my thoughts and my limited experience with basic physics.
>
>
>
> Bruce Mowbray
> trainhead_@_mymail.emcyber.com
> http://www.geocities.com/trainhead391/
> TMB Manufacturing and Locomotive Works
> 1 1/2" Scale & 2 1/2" Scale (Narrow Gauge) Live Steamer
>
>

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