What's On This Scott's No. 1009?

I have not been able to find anything written about the marking on this stamp, Scott's No.1009. I am hoping that someone in this forum can help me out. Thank you very much.
hawkstamp

The black marking is a duplex cancellation, common for the time period.

Here is an example that is similar to yours, of the full cancel.



They are called Duplex cancels, because they consist of two parts, a Circular Date Stamp (CDS) containing the name of the city and state as well as the date, and the other part is the Killer, which marks the stamp to show it was used (often oval or "football" shaped).

Here is a picture of the business end of a Duplex Stamp (slightly different design from yours) which was previously posted on SCF.

Great, that sure was quick. Thank you very much. One additional comment I have is that under magnification, it appears as though there is hand writing under at least one of the lines. That fact made me very curious and I wonder if you can see it on my scan. If there is, how did it get there, to be precisely under the marking of the cancellation. Perhaps you have a thought on this. If you do,please let me know.

All I see is little streaks of ink being flung in various directions as the stamp comes down onto the cover.

smauggie,
Thanks again for your help. It's always good to be able to come to this forum and get help from experienced collectors.
hawkstamp