Let ψ denote the inclination to the horizontal, and wδs the weight of an element δs.
A combination of red and blue is presented by Φ (mistakenly marked on map No. 23 as ψ).
The radius of curvature and normal are each equal to c sec ψ.
A small Greek Lexicon, from γ to ψ inclusive, also filthy, with several crude but vivid illustrations in red ink.
The elimination of ψ between the equation of conservation of angular momentum about the vertical, viz.
The Greek letter psi. Entries beginning with this character are alphabetized under psi.
psi 1 (sī, psī)
Symbol ψ The 23rd letter of the Greek alphabet.