\ \ Y \ \ \ \ V / I / i ? / / \ i \ / /3 , r Standard Type (+ V) n-Type Double sphere type (co-tvoe) Tapering type / T \ i “Y /5 N f i 1 1 5 I \ r) I k / ( > r Vestige Type Parabola Type Catenary Type iy-Type / \J \ \ \ / I 9 / \ f ' ÏÏ j \ 11 i 1 0 1 V/ ) V 11 / \ I \ YY \ 11 h