One of my sideline collections is New York Central Railroad. My father-in-law was a lifelong employee so this is in his honor.

A particular fun hunt has been finding NYC perfins on NYCRR stationery. Here are a few examples.



Postmark is Oswego (I think) NY, Nov 15, 1936. The perfin is more clearly shown here:




The next cover is dated July 4, 1942 (my birthday, and July 4 is very hard to find) from Newton Falls, Ohio (Trumbull County, which is also my birth county):



And the perfin:



Notice that this perfin is both inverted and reversed.

A final cover is dated Sept 6, 1951 from Palmer, Mass:



with the perfin seen here:



Notice that the perfin is off-center but still identifiable.

There's more to mine out of these covers but right now I'm just focused on use, identification and the postmarks.

Roger