Archaeologists are comfortable around headstones. A trip to the cemetery is pretty much another day at work, or in the classroom.Doug Wilson, archaeologist at the Fort Vancouver National Historic Site, brings college students to Vancouver’s Old City Cemetery for summer field-school sessions. In addition to learning how markers are cultural resources, the students document the information on the weathered stone monuments. And we’ve all been seeing plastic tombstones planted in front yards the past few days, signifying nothing more serious than an ongoing Halloween candy binge.But there was one collection of grave markers that sent a chill down the spines of local archaeologists. It was discovered a few years ago, before the Vancouver Land Bridge and the two cabins representing the workers village were built on the Fort Vancouver National Historic Site.Back then, the area east of Interstate 5 and north of state Highway 14 was a blackberry patch. As maintenance workers hacked through the brambles, they found Army grave markers.“I sucked in my breath when I heard on the radio that military gravestones had been found,” Fort Vancouver Superintendent Tracy Fortmann recalled.“It was startling. To see a number of headstones, it’s not something you anticipate while cleaning out blackberry bushes.”Park Service archaeologists started to sort things out. The stones weren’t neatly arrayed; they were scattered around. Some stones were broken. Some markers had other issues: typographical errors.