Lesson 1: Water flows downhill
Lesson 2: The bigger the hill, the faster the water goes
Lesson 3: Stuff happens when water flows downhill
Lesson 4: Fish like to eat and they hang out where the food is
It's sorta like my old pal Sonny Fry used to say (to paraphrase):
Streams, Streams, the wonderful Routes,
The more it rains, the more they Shoots,
The more they shoots, the fuller the creels,
And we get fish for all our meals.
And may all our Thalwegs be long and bubbly!

