¶ Mast in the earth
← Mast in the Earth | Fast in the Earth (1) →
Index Entry
“If I wanted to have a mast on the face of the earth it would take me a minimum of three legs and a tension member to hold those legs down so it takes four members. I can have one compression member and three tension members or three compression members and one tension. It always comes out four. I can put the pole in the ground and we will find that it still comes out four. We might have the mast bending over and it would take two tension members to hold it up, that is called a gin pole, and then it takes a fourth member of gravity to pull the other end down so there are four members operating. You could do that with two compression legs–sometimes called a jack in the Navy, and one tension member, and gravity–four members every time. So there are four degrees of freedom and the local twist you will remember which gives us twelve. I began to see then that we would always have these kinds of fournesses operative.”
¶ Citations
- Oregon Lecture '65, p. 201. 10 Jul’62
