Sonnet for a geometry teacher

Wisconsin poet Ronald Wallace has fun with math-words in the following sonnet that celebrates a teacher of plane geometry. 

     Mr. Glusenkamp      by Ronald Wallace

     His gray face was a trapezoid, his voice
     droned on like an ellipse.
     He hated students and their noise
     and loved the full eclipse
     of their faces at the end of the day.
     No one could have been squarer,
     and nothing could have been plainer
     than his geometry.

     He didn't go for newfangled
     stuff—new math, the open classroom.
     And yet he taught us angles
     and how lines intersect and bloom,
     and how infinity was no escape,
     and how to give abstractions shape.

"Mr. Glusenkamp"  is found in Wallace's collection Long for This World:  New and Selected Poems (University of Pittsburgh Press, 2003).