This cover is one of my earliest pieces. It is an 1819 stampless cover with a Philadelphia postmark stamp. According to the Phillips "American Stampless Cover Catalog," such a cover traveling from Philadelphia to Boston (about 300 miles) should cost 18 1/2 cents.
Here is my question. In the upper right corner there is writing that is old and could be original. I see the number 18 and then a squiggle. Is this a mark denoting the 18 1/2 cent postage rate? Is that how this would be done? Is this wishful thinking on my part that it would be marked this way?