The two pictures of trolley coaches comes from the British Trolleybus Society. the top picture is dated 8/8/59 by Graeme Bennett and the second one is not dated and is from Ransomes, Sims and Jefferies from the BTS. The map shows their tramway operation from 1916 to 1954 and their trolleybus system from 1950 to 1967. Since I had this material in my archive for over 33 years and the New Zealand transit operations are not that known in the United States , I decided to post the information for those researchers and others that will find this information useful.
The New Plymouth operation was a small one, and it was quoted in the source above that " ... thus started the smallest municipally - operated electric streetcar system in the world using the overhead system of current collection, serving a population of only 8,000..." p. 36. Although before World War I a trolleybus system was desired but a streetcar system opened on 3/10/16 and consisted of about six cars. The trolleybus system started in 1950 with four trolleybuses. The system lasted until 1967.