N&W CPLs, the last generation
NW Mailing List
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Tue Dec 31 12:14:38 EST 2019
Your error is forgiven. For your penance 1)stay around and stay healthy so
you can keep giving us your information/recollection/stories; 2)please
consider coming to a Society Convention some day. Turnips are hardy; they
can get by four days without you.
Not asking much
Who can't really give absolution but was educated by Jesuits
On Tue, Dec 31, 2019 at 10:20 AM NW Mailing List <nw-mailing-list at nwhs.org>
> Gentlemen, I must confess to a gross slippage-of-the-mental-cogs on my
> It was the PL-3s which the N&W did not use.
> The PL-2's were developed sometime around 1940, and its optical system
> provided for a horizontal **spread** of the forward-focused light about 30
> percent greater than that of the original PL-1 optical system.
> Thus, the PL-2 was obviously designed for railroads which had a
> significant amount of curvature. It was the perfect PL signal optical
> system for the N&W.
> The PL-3, on the other hand, seems to have been designed for concentration
> of the beam of light emitted and, thus, for range of readability. It was
> apparently only bought by the PRR and the Long Island RR.
> The tragedy is that the correspondence and literature on why these
> different optical systems were developed seems to have been completely
> lost. The best one can do is talk with some of the retired signal
> engineers from US&S, none of whom go back to the day when all this signal
> technology was being developed.
> My apologies, Had I sat on my post for a day or two, the error would have
> leapt off the page at me.
> I accept my error, and regret it.
> Yours penetentially,
> -- abram burnett
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