The eastern boundary of the Louisiana purchase was the Mississippi River, from its source to the 31st parallel, though the source of the Mississippi was, at the time, unknown. The eastern boundary below the 31st parallel was unclear.
An A-frame pool ladder is a great above ground pool ladder designed for stability and safety that is perfect for above ground swimming pools Pool owners with small children can provide an extra layer of safety with the fold up mechanism or locking gate.
As far as swim ladders go, this link shows the kind we installed 15 yrs ago and it is still working just fine. We chose the 3-step model which puts a rung into the water on my boat. [The swim platform is 1 ft above the waterline.] It is nice to not have a ladder on the platform which can stub toes, etc.