About the Manning Brothers
Henry Lucius Manning began acquiring land in the Swan River Colony in 1840 and his agent in the colony was James Woodley Davey. Davey died in 1852 and later Henry decided to send out his brother Charles to manage the properties (eventually including this one).
The Manning's estate was Canning Location 37 which comprised a large rural property of 1,386 acres (560 hectares) along the Canning River, bounded by Henley Street, south to Mount Henry and east to Clontarf. The land was originally allocated to Thomas Middleton on 3.12.1830. It was purchased by Henry Lucius Manning in 1856 for £500 ($1,000), although it is believed that the Middleton family resided on the property until at least 1870.
In 1936, 167 acres of the land was sold to the Christian Brothers for the construction of Aquinas College.
Henry was an absentee landowner who made no use of this large area of native bushland, but whose descendants profited from its gradual sale. The estate was held by various members of the family until much of it was resumed by the State Government in 1948 for development by the State Housing Commission as a ‘model suburb’. This suburb is what we now know as Manning.
I wasn't able to find a picture of Henry Lucious Manning, but was able to find one of his brother Charles, so I have included it as the background for the cache page. I was not able to locate the Indigenous history of the site.
About the Cache
The cache is a small bison tube. It's probably only a difficulty 2 or 2.5, but because it is at muggle central I bumped it by 0.5.
Good luck and have fun! 
Congratulations to C10 & B12 on FTF! 