Sketches four and five are referred to here as a pair of companion images because the demands of four are fulfilled by the supplies delivered in five (the laws of supply and demand are met). "This" image is shared between the 324 Patent and the 407 OED. These two projects were worked on simultaneously therefore stimulus for one process spilled over into the other process. At times, the design processes converge and other times the processes diverge. The text of the two Mathematicians conversing has not come out very clearly here. The mathematician staring at his own shoes is the introvert. The mathematician staring at the other mathematician’s shoes is the extrovert. It’s a joke amongst mathematicians. “Sick, but social.”