2 Drew the smooth charet of sad Cymodoc{e"};

charet > chariot

3 They were all taught by Triton to obey

Triton > (Son of Neptune and Amphitrite, and thus a nephew of Cymodoc{e"}; his chief characteristic is his shell-trumpet, which he blows to quieten the waves; for his command over dolphins, see Myth. 8.3) obey > be obedient; submit

4 To the long reins, at her commandment:

commandment > command

5 As swift as swallows, on the waves they went,

swallows > (Which, besides having a fast and liquid flight, will skim the surface of fresh water in order to drink)

6 That their broad flaggy fins no foam did rear,

That > [So that] flaggy > drooping (Spenser's knowledge of dolphin anatomy seems to have been gained from woodcuts in medieval bestiaries and the like) rear > raise