It's been answered plenty of times, the OP has done it correctly here. If you bridge the interfaces and move filtering from the bridge members to the bridge interface then the resulting interfaces will behave like switch. It will be much slower than even the cheapest switch (in most cases) but there are advantages. You can filter traffic between the ports for example. There are legitimate reasons to do this, buying a quad port nic just yo bridge them is not one of them.
I have 3 interfaces bridged on my home box here. It has 10 NICs, they aren't removable and I don't need 10 subnets. The box cost me £40. ;)
Steve