Crazy laughing

It's the morning rush hour. Walking fast along the platform and jumping into the tube train as far towards where I need to alight as I can get before the doors close. A man gets on behind me. Slightly odd look about him. A tooth sticks out beyond his closed lips. Boggly eyes. As the tube train doors shut something tickles him and he begins to laugh heartily. He laughs long enough for the other passengers to go from staring in vague disbelief to some catching the infectious laugh finding themselves tittering to themselves and others burying themselves in their papers or music. Then he stops. The momentary reconnection to each other evaporates. At the next station people crowd on shoving and standing like rocks holding  space like their lives depend on it.