I know it works, but never understood how: Batt/Alt/Start

[roccaas]

The battery feeds power to the starter through the negative cable/post.

When the Alt/Gen takes over, HOW does it recharge the battery:

1. Alt/Gen>Junction Box>Ammeter>Junction Box>Starter>back up the negative cable to the battery?

OR

2. Alt/Gen>Frame/Block Ground>through the frame>positive cable to the battery?

If 1, does the negative cable change direction of flow to let the power back into the battery? How does this work if the battery is still providing a buffer to the whole electrical system, and could be feeding some power from the battery to the system?

If 2, is it the logical idea that electricity flows from positive to negative?

3. It's really just magic and little elves under the hood, so just accept it!

This whole theory is hard for me to grasp having grown up in an era of Negative Ground, but even in 1978 I was puzzling on this as I replaced (X3) the starter on my '73 LeMans!