If you attempt to use the sink the way a person of modern times would, you wind up either freezing your hands or burning them. The correct technique for using the sink is to stop up the sink, and then turn on both faucets. Then the user tests the water until the mixture in the basin reaches the right temperature. After this point, he or she begins to wash hands in the sink, and may even dump in a bar of soap until all the water becomes soapy. You could investigate the technical details of setting up a sink, if you want to know more about the design concepts behind this.
Modern sinks use a single faucet and one or two handles, avoiding the complex two-faucet design.
Continue with a look at some soap , with naphtha.