Our 29th Street half of a block drained to the southwest. To level the machine shop / house building a two-foot infill had been excavated to support the southern house half of the building. With extra room left for a sidewalk around the house, this infill sloped down to the natural lay of the land. Covered with grass, those two feet of sloping ground became an endless source of amusement for we three toddlers. 

It was heaven on a summer day, rolling down the cool grass. The green blades tingling our skin. The rich, moist smell of plant and soil. 

In 1950, when I was five, the City of Boise built their first wastewater treatment plant two miles down river from our place. A 1947 bond had passed voter approval by 91%  — 25 years before the federal Clean Water Act required keeping our waterways clean for fish and kids. This sewer plant had a gigantic grass covered berm, perhaps to contain wastewater should one of the large tanks burst. 

As a big boy of five, the little two-foot slope in front of our house had gotten to be about one roll. Our folks were soon driving we kids down State Street for extended rolling in the grass.

From one of dad’s 16mm movies I see he took the opportunity to enjoy some summersaulting himself.  I don’t remember the place smelling of sewer, but the berm along Lander Street was on the prevailing up-wind side of the wastewater plant.

And that is how gravity became friends with my sisters and I long before I knew there was a word for it.