Speed Board (?) question

[BR&P]

I just got done working a couple weeks on a segment of the former CRI&P. Saw a couple signs, shaped roughly like a canoe paddle stuck in the ground. At the top was a large "C", and below that a horizontal stripe which might have been red when the thing was in good shape. Below that was "40".

It appears to be a permanant speed board for 40 MPH, and I'm wondering if the "C" meant "Curve" or "Curves". There was one in each direction perhaps a half or 3/4 mile apart. The line is 25MPH today, and it makes you appreciate how the old-timers kept things maintained if they used to have to SLOW DOWN to 40!

Anyone with an old Rock Island ETT or rule book who can confirm this? Or am I all wrong?

[57A26]

Yes, you have a speed restriction sign for a curve.

From a RI Special Instructions in a 1969 ETT. "Curve speed sign indicates speed restrictin for curve 4000 ft. from sign except on subdivisions where maximum freight train speed is in excess of 60 MPH sign to be placed 6600 ft. in advance of curve."

The RI also used a similiar sign for zone speed. Those had a "Z" above the numbers. The shapes where slightly different and the diagram in the SI shows the Curve sign yellow, the Zone sign white.

It's placement is almost the same, except where the zone speed goes to a higher speed, the sign is placed where the higher speed begins. For both signs, if there are two numbers, the higher speed governs passenger trains and the lower speed governs other trains and engines. Where there is only one number it governs all trains and engines.
JLH

[BR&P]

Thank you very much. I knew someone here would have the answer.