Let us now take the vector of the 1st kind

(57) Ω = _i_ω[Φψ]*

with the components

Ω₁ = -_i_ | ω₂ ω₃ ω₄ |

| Φ₂ Φ₃ Φ₄ |

| ψ₂ ψ₃ ψ₄ |, etc.