"You are the Conductor on..."

[Anonymous]

There were a series of articles related to local switching problems printed in past issues of MR. The article would present a switching problem in a town on a diagram with various do's and dont's. You would be challenged to solve the problems presented you on the train and a set of switching moves would be hidden elsewhere on the issue. (Answers)

My problem is this: None of the stacks of MR I have contain any of these articles. Does anyone know of the year and month these issues contained the articles? Were there a limited number of these articles or was it a regular feature?

[fiatfan]

If I recall correctly, the switching puzzles would appear once or twice a year.  I haven't seen any for some time now.  To my knowledge, they were not a regular feature that appeared on a scheduled basis.

Tom