Hi all.

        I've been monitoring the excavation of a trench for the railroad through
Reno, along the original transcontinental route. One of the things we've
found is a substance that is similar to coarse sand in grain size, texture,
and ability to pack (I couldn't get vertical walls, they all ended up being
at the angle of repose...) and a uniform black that rubs off on your hands,
clothes, etc. Normally, there's nothing else in the deposit. A couple of
deposits have been rather random in shape, but one was in an approximately
cubical hole about 1 meter on a side. I was thinking that it could be the
remains of coal used in the train boilers, consequently subjected to high
and extended heat. But coal isn't a common fuel in the Great Basin, so I
have no idea what coal ash should look like. Could someone accustomed to
coal-fired heat give me a clue what remains when coal is well burned?  Ashy
(like wood)? Mottled color or uniform? Black or shades of grey? Can I
expect a scent after its been buried for a century (I detected none)? Or
??? Unfortunately, I have no picture, but visualize black sand.

Robert C. Leavitt