A poster to HCVC forum placed a photo of a three-wheel lorry running as a
parade item in the 1930s.
This sparked a lot of discussion and research.
A few members found more on the glass company; others found more on the
obelisk.
Several more photos were posted, with the source unstated.
I tried in the TDU archive, and found only one of them.
One colour one looks suspiciously like a Noel Reed.
I suspect that the lot came from a local-history facebook site. These are
notorious for stealing without crediting, and without posting the caption
information too.

Three-wheel tractor of Australian Glass Manufacturers with trailer, ~1930s.
Grimwade Glass started in Melbourne, but expanded interstate.
Great reading: www.ozcrowncrystal.com/period1.html.
In 1926, AGM launched a subsidiary company - Crown Crystal Glass Pty. Ltd. -
to produce crystal, cut, pressed and blown glassware (including pyrex) for
industrial and domestic use. By the late 1930s, the company was producing
9634 different types of glass bottles and containers.
In 1968 Crown Crystal Glass became partners with American company Corning
Ltd., becoming Crown Corning Ltd. The partnership ended in 1988.
The story of the Hyde Park (Elizabeth Street at Bathurst St) obelisk; it's
not a war memorial. Unveiled in 1857 by the then Lord Mayor, George
Thornton, it served as a sewerage duct vent to allow the escape of noxious
gases from the sewer (although it now ventilates the stormwater system,
following works to separate Sydney's sewerage and stormwater systems). The
Hyde Park Obelisk was the first special sewer ventilation shaft built in
Sydney and in NSW, and is the only example of a sewer ventshaft constructed
of sandstone within the Sydney Water system. It was modelled on Cleopatra's
Needle on the banks of London's River Thames. The overall structure is 22
metres high, which comprises a square sandstone base 6.5 metres high. The
vent at the top is a filigreed bronze pyramid.
On 7.11.14, the obelisk was covered with a giant pink condom as a temporary
installation to raise awareness about hiv, primarily in Sydney's homosexual
community.
It is also jokingly referred to as Thornton's Scent Bottle.

Here are the only two which I could find on TDU:
http://tdu.to/a16609/The_Obelisk_Elizabeth_St_Sydney.jpg (crop of the one
via HCVC).
http://tdu.to/a16612/Bathurst_St_from_George_St.jpg Obelisk and horse
vehicles.

Enclosed: Five via HCVC. People may be able to find TDU references and
credits.

Hyde Park, Elizabeth St - obelisk, horse vehicle.
1950s Hyde Park, Elizabeth St - obelisk, R1.2865.
1411xx Hyde Park - obelisk, giant condom.
19090825-Hyde Park, Elizabeth St - obelisk, 155 [L155? 15S?]
Hyde Park, Bathurst St - obelisk, horse vehicles.