Why don't these multiplexers work?
From a quick glance at the picture it looks like you don't have anything attached to Vee (or enable) You must have Vcc, Vee and GND connected. Enable needs to be pulled to ground. 

If your input signal is bipolar (swings positive and negative) you need to connect Vee to a negative supply that is greater than the maximum negative swing of your signal (e.g. if signal is +/- 4V then Vcc = +5V and Vee = -5V)
If it's not bipolar then just connect Vee to 0V (GND)