Need Information About Flag Cancellation

first, I'm sorry if my post is repost, cause I can't search about this cancellation information, especially at my country Indonesia. I just starting for learn about U.S Postcard and U.S cancellation machine.

What I'm going to ask is, what name for this cancellation, history and value







and for this cancellation at this postcard.is that whether ordinary, there is 2 cancellation at one postcard?





best regard from me in Indonesia...

Top 3 are 'flag cancels' from the American Cancel Machine Company. Some are scarce, these are common varieties- value nil. There are almost 8 thousand different US flags. .

The last card: The domestic US rate for postcards and postal cards was 2 cents from November 2, 1917 - June 30, 1919. This card was originally mailed plain, held for the additional 1 cent postage then sent on to the recipient. Note the "1c due" at the upper left and the layering of the stamps and cancels - the Jefferson imprint has 2 sets of wavy cancels, while the added adhesive has only 1 cancel over it. It was also missent to Hartford PA, where the address was re-written more clearly to get it to Hartford, Conn.

Thank you very much @chasa and @John Becker for your information..
best regards

I just wondering, the number (2 and 12) at the flag. is that for number machine cancellation the city?

Yes, the numbers are those of the particular machine cancelling the item

Peter

thanks @Peter4522

I just received a flag cancellation on a post card from Sleepy Eye, MN 1911

Sleepy eye MN has some great history. I'd imagine it was a pretty small town in 1911 since there are only around 3000 there now. I believe they named the town & lake after Chief Sleepy eye, a native American Sioux known for having droopy eyelids.

I was born in the Sleepy Eye hospital in 1950, my parents lived in smaller community of Evans. I have a 1950 atlas which list the population of Sleepy Eye ay 2923.

Well hello fellow Minnesotan :)