The descriptor "first"should always be used with caution, particularly in relation to motor vehicles. The Shearer Steam Carriage, which made its first public appearance on South Australian roads on 5th June 1899, is sometimes touted at Australia's first motor vehicle.
What we can say for sure is that the Shearer was not the first motor vehicle to take to South Australian roads. That Lewis produced a motor vehicle that pre-dated the Shearer is evidenced by the following extract from The Critic on 11th March 1899:
Unfortunately no contemporary photo has been found of the motor triplet in action, but it must have made quite a sight. One of the early Lewis workshops was located in Freeman Street, and so the experimentation with the triplet was taking place close to home. That said I can't imagine that a machine with such a long wheelbase can have been suited to city streets, and presumably the testers must have ventured to more open roads or a bicycle track to fully assess the performance of the machine. Aside from this one reference, we have found no other contemporary mention of the triplet.
If the team of Vivian Lewis and T.P. O'Grady were genuine innovators in the motor industry, one or both of them had a rather endearing quality: they liked to hang on to historic junk. Later we will see how the 1900 Lewis car survived within the company for decades, but here it is enough to look at the Lewis Cycle works c1904 as captured in one of the photos from the Lewis album:
Hanging high in the rafters above the cluttered work bench we see what is surely the remains of the motor triplet. By this stage - some 5 years after The Critic saw it under power in Freeman Street - it has been stripped of its tank and motor, but the belt rim is still fitted to the back wheel.
The additional strutting to the rear of the machine was no-doubt related to the engine mounting arrangement.
In an interview with a reporter from The Critic which appeared on 22nd April 1908, O'Grady commented on the motor triplet:
By the time he was interviewed for The Mail for their September 13 edition in 1913, O'Grady had reflected a little more on the performance of the early versions of the motor that appeared in the triplet:
Glimpses in photographs 02, 10 and 11 add a little to our knowledge. The triplet featured flat belt drive, toe clips, down-turned racing handlebars at the front, and the the top tube was duplicated at least for the front third of the frame.
Beyond these scant details, we know little of the configuration or performance of the machine. Additional information relating to the motor triplet would be most welcome. Perhaps someone can supply a photo of the beast in action?