Question re N&W Manual Blocking Procedures

NW Mailing List nw-mailing-list at
Mon Mar 19 12:49:23 EDT 2012

I am probably at least 50 year too late in asking this question about N&W Manual Block procedures, but here goes...

The Clearance Card, N&W Form CT-37 1/2 (revision of 2-1-1941,) which was still in use when I hired in 1964, has a curious final line, which leads me to question how the N&W handled the manual blocking of trains in territory where Time Table/Train Order was the method operation, and on which the Manual Block System had been superimposed as a second level of protection.

I'll attach a scan of that Clearance Card.  The last line on the card is a fill-in-the-blanks line reading:  "Signal is displayed for ___ and ___ to meet (or pass) as per Order No. ___.  Except as stated, Block is clear."

This line was obviously provided for a situation where trains meet (or pass) at a "blind siding" (no open Train Order Office.)

This raises the immediate question:  When a train received a Clearance Card with this line filled out, what was done with the Manual Block Signal?  Was it held at Stop, or raised to Permissive, or raised to Clear?  And furthermore, if the signal was held at Stop or displayed at Permissive, at what speed did the train proceed to the meeting/passing point?

Unfortunately, I never worked over any N&W territory where the method of operation was Time Table/Train Order + Manual Block System.  And I don't think I've ever seen the situation addressed in any of the old rule books.

-- abram burnett

“No man can hear his telephone ring without
wishing heartily that Alexander Graham Bell had
been run over by an ice wagon at the age of 4.”

  --H.L. Mencken

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