Thanks for posting, good history lesson. How many people know that the last one posted, the French 4-pounder "Swedish" model, was a primary weapon of the US artillery during the Revolutionary War? Henry Knox had many of them bored up to 6-pounder. There are probably a couple dozen or fewer of these pieces surviving, most still in the hands of the US Army. Most are outside dissolving in the acid rain, expecially at Ft. McNair, Washinngton DC. I've written to the Army about that situation and the person in charge recently told me the "outside" collection at Ft. McNair is now slated to move to a covered location at the new Army museum at Ft. Belvoir VA.
