The description for the photo on the right reads:
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Source: New Zealand Herald, 11 April 1931, Page 6
When the bus was trialled in Auckland in February 1931, it was described as 'Auckland's rocket.' It made no noise on starting up and went 50mph out to Point Chevalier, and 20mph up Parnell Rise.
In 1932, the paper again reports a steam bus undergoing road trials for White & Sons of Thames - destined to be for the Thames to Auckland Passenger route. New Zealand Herald, 23 July 1932, Page 10
Following these reports, there is no further news on the Steam bus manufacture at Thames, and one can but conclude the scheme did not continue and sadly the orders did not flood in as was expected.
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Further information located, posted 13/01/2015
First two items from "Men of Steel" by C W Vennell