Browning's "Saul" certainly is pentameter and seems to include enough anapests to make it classifiable as anapestic pentameter. As is typical of anapestic lines, many begin with iambs, and there is also substitution of other triple feet, such as amphimacers ( / * /).
 

  *      /   | *   * /  | *   *     /  |   /        *       /   |    /           *    /
He stood as erect as that tent-prop, both arms stretched out wide

  *   *      /   |   /       *     /  | *  *    /  |  *   *     /    | *    *     /
On the great cross-support in the centre, that goes to each side;
He relaxed not a muscle, but hung there as, caught in his pangs
And waiting his change, the king-serpent all heavily hangs,
Far away from his kind, in the pine, till deliverance come
With the spring-time,--so agonized Saul, drear and stark, blind and dumb.