was the importance of keeping the floats pumped dry at all times. CG, all up weight, slosh in manoeuvring flight.
Most of the water goes into the rear chambers moving the CG aft as the rear of the floats are frequently under the water. If there is a problem in the bow chambers then there’s a leak.
When a seaplane is on the water you can gauge its balance by the way it looks.
A bit like with a Cessna 172 on wheels... It will tell you a lot by its attitude.
As for slosh, the chambers have bulkheads to reduce the amount of slosh to their short lengths. Floats should each be able to support the aeroplane on the water though often this is not true in Luscombes, and J3 Cubs that are often under floated...
Like everyone I had to learn, and in recent years I have taught the seaplane rating in Canada, both in floats, and in flying boats.
They are easier than tailwheel aeroplanes, but at the same time less forgiving in some circumstances, it’s a different skill.
There are plenty of stories...
One involved the pilot being encouraged to take hunters and their kills out of a lake.
He was unwilling, but the hunters told him the other guy flew out like this last year.
They crashed of course, and the hunters told the pilot that they got a few hundred yards further than they did the previous year.
This is very common in Canada, where young green ‘bush’ pilots are asked to take unreasonable loads in aeroplanes and crash for it.