In which we are breaking up the clumps of clay and really crumbly sandstone from the site to make cob. This soil doesn't have much structure. You can actually break the "rocks" by hand and they shatter into sand. If you put them in a cob wall as is they would crumble over time. The good news is there are also chunks of pure clay in this soil and when we break them up everything sticks together marvelously. Watch for part 2 of this video as we build the rocket heater.