WWI ARCS Voluntary Motor Service certificate

It is not known who Mrs G. McColl was, but she did her bit by allowing her motor vehicle to be used to transport returned servicemen and women.
Sir James Oswald Fairfax (1863–1928) was the Chairman of the Australian Section of the Empire Press Union as well as Chairman of the New South Wales Division of the Australian Red Cross Society.
Miss Claire Garvan was the Hon. Secretary involved in coordinating the cars to be used in the Voluntary Motor Service. She was recognised in the London Gazette of 19 October 1920 for services as a voluntary motor transport worker in New South Wales.

An article from the Sydney Morning herald dated 3 May 1918 explains the service:

"The Minister for Recruiting has
called on owners of motor can to
register their cars for the public service,
especially in connection with the
conveyance of home-coming sick and
wounded soldiers.
The chairman of the executive,
N.S.W. division of the Red Cross
Society, has published an appeal point-
ing out that the special service requires
a very large number of cars,
There are 7000 motor cars registered
in Sydney, but only 400 to 500
have been offered. Our cars are called
out in turn through notice in the daily
Press at the instance of the Red Cross
motor service, under the direction of
Miss Claire Garvan.
It has only to be brought home to
car owners that the duty is imposed
upon them to render this public service,
and the number of cars placed
at the disposal of the voluntary motor
service will be increased tenfold.
Thirty cars are called out for the
service of a small detachment of soldiers
returning home to-day, the
Governor's car being of the number.
The larger the number enrolled the
less often will the demands be made
on the owners. Owners provide their
own drivers ; there need be no damage
done to the cars; the self-denial is
trifling. I hope therefore that owners
will respond with alacrity to the requirements
of the Minister for Be
cruising and to the appeal of the Red
Cross.
* MARGARET DAVIDSON,
President of the
New South Wales Division,
Australian Branch of the B.B.C.,
May 2, 1918.
Owners who are willing to register
their cars with the service are kindly
requested to communicate with Miss
Garvan, Red Cross Motor Service, 26
Castlereagh-street, Sydney.