You could turn on the first one for two minutes and turn it off. Then the middle for two minutes and turn it off. Then the last and run inside. If it is on then it is the last is it. If the bulb feels hot then the middle one. If only warm then the first.
Or here is a better method...
Turn on the first one for like two minutes then turn it off. Then turn on the middle one run inside, if the light is on it is the middle one, if it is off feel bulb for warmth. If the bulb is warm then the first one turns on the light, if not then the last one does.
Is this right?