They got two things they have been waiting for a very long time in Coatesville last night.

An arrest in the wave of arsons that had many residents living in fear.

And a good night’s sleep. Or at least a better night’s sleep.

Officials yesterday afternoon announced the arrest of a 19-year-old Downingtown man in the wave of domestic terror – in the form of a series of arson fires – that had residents afraid to go to sleep at night.

Roger Leon Barlow, 19, is believed to be responsible for nine of the fires, including the conflagration that roared through a block of row homes, destroying 15 homes, displacing scores of residents, and pushing the already-tense city over the edge into a siege mentality.

Last night a second man was charged in an attempted fire at a local restaurant.

Barlow is from Downingtown, just a stone’s throw down Lincoln Highway from Coatesville. Mark Gilliam, 20, is from West Bradford, just outside Downingtown. Here’s another troubling thought: He’s a volunteer firefighter.

The city’s problems are not over. There are a couple of questions that come to mind. One of them would be why? Why does someone do such a thing. Chester County District Attorney Joe Carroll yesterday referred to Barlow as a pyromaniac who liked to watch things burn.

But there is a more important issue that hangs over this case like the smoke that swirled around these fires.

Barlow is charged in nine of the fires. There have been 24 arsons in the city and surrounding towns since the start of the year.

Maybe Barlow or Gilliam eventually will be charged in even more fires. If not, who set them? A couple of suspects were charged in the arsons that plagued the region last year, but the fires did not stop.

Maybe they will now.

And maybe, just maybe, residents can sleep at night.