The New Zealand E class locomotive comprised a single Mallet steam locomotive operated by New Zealand Railways (NZR) from 1906 until 1917. Classified as E 66 and nicknamed Pearson's Dream after its designer,[1] it was an experimental Mallet locomotive designed to work on the Rimutaka Incline. The "E" classification was previously used by the Double FairlieE class of 1872-75, but the classification was free as they had all been withdrawn by the time E 66 entered service. After the withdrawal of E 66, "E" was again re-used on the battery-electricE class of 1922. It was the only Mallet locomotive to operate for the NZR