"Sawney Beane" wrote in message
...
"Daniel J. Stern" wrote:

On Fri, 16 Dec 2005, Sawney Beane wrote:

"Car Talk" is a syndicated radio show in which the Tappet Brothers,
Click and Clack, answer questions about automotive mechanics.

No, it's an NPR radio show in which those two buffoons give reliably
incorrect car advice in between drunken-bum guffaws at their own dumb
jokes.

I have not found their advice or their brain teasers to be reliably
incorrect. That's why they've taken me in so many times.

Our RR gage came from the width of Roman chariots? (I wrongly
called the width the wheelbase.) The evidence for the myth is that
ruts in the Roman pavement coming out of a stone quarry are as far
apart as modern rails. Saying that was the width of chariots is
like saying jeeps and humvees have the same width as each other and
as eighteen-wheelers.

Maybe each of the early railroad builders used a different Roman
chariot as his gage, and that's why there were so many widths.
They may have been relatives of Click and Clack.

The outside measurement of modern rails is very close to five feet.
I think the original specificaton, in the days of wooden rails,
was for wheels five feet apart at the outside. Wheels and rails
evolved, but new wheels had to fit old rails and new rails had to
fit old wheels. I think that evolution is why the outside
measurement is slightly different from five feet nowadays.

In the US, the most widely used gage was 4' 8 1/2" measured between the
*inside* faces of the rails. This was chosen because most of the early
locomotives were brought over from England, and that was the gage used
there.

Some other gages were used for specialty service, such as mining and
logging. When railroads started interchanging, they had to standardize and
they chose the most common gage. So for the US and Canada, it has been 4' 8
1/2" now for over a hundred years.

daestrom