upthrust
Buoyancy
salt
A simple clay ball and straw will work just fine..
because elasticity of clay is very small, so when reaction of wall acts on the clay, clay cannot withheld the force and it deforms
straw and unbaked clay
straw and unbaked clay
you
clay and straw
A light grey Tennesee ball clay
adobe bricks made from clay and straw
If you're good with your hands, you can make a cube out of one ball of clay,or a cubical frame out of one straw cut into 12 equal pieces.Ohhhh wait ! Now I see what you're driving at. Maybe the little clay balls arewhat you use at the corners to stick the pieces of straw together. OK.You still need 12 pieces of straw all the same length, and then you need eightballs of clay to stick the corners together and make a cube.I apologize for giving you the answer. Now you'll never think it through on your own,and you'll never understand why that's the answer.