It's large, heavy and Victorian and our walls are also Victorian and so far I have managed to cock it up completely.
I've put two little brackets on the top edge (which is the soundest part of the edge) with a hole in each (you know the brass ones - the sort you might hang a mirror with) and have been trying to drill into the wall but the trouble is, as I anticipated, that the walls are made of shit and horse hair, and I can't seem to find any studs in them. Only space and impenetrable brick, with crumbly plaster in front.
I was intending to support it with further screws direct through the back board after I had done this and also thought about putting brackets underneath it as well, though they would have to be quite small as there is a dado rail going up a little way beneath it (more drilling fun no more nails probably )
I'm thinking of putting it outside on the pavement and waiting for someone to take it away and give it a home.
I have had the thing for many years, it was a 'foundling' which someone else chucked out and then charged me £15 for when I asked if I could take it 
Glass fronted, 8" deep and about 36 wide by 47 tall. Bloody thing.