It's been more than 150 years since Abraham Lincoln issued his Emancipation Proclamation, freeing enslaved blacks in the Confederacy and paving the way for freedom for all, regardless of race, throughout the union.

A century and a half later, slavery has faded for most from harsh reality to distant memory - but vestiges still remain. Slavery should not be forgotten, believes Gwen Ragsdale, of Philadelphia's Lest We Forget Black Holocaust Museum of Slavery, but for too many, it has been. On Feb. 25, Ragsdale took her museum's traveling exhibit to Oakcrest High School to ensure its students understand the impact slavery still has to this day.

English teacher Dianne Robbins, who brought the museum to Oakcrest for Black History Month through a grant from the Ralph W. Martin Foundation, said seeing slavery-era artifacts with their own eyes reinforces for the students the lessons they've learned in school.

"When I saw her laying out the stuff this morning, that just put everything in perspective," Robbins said after Ragsdale's presentation. "You can talk to them so much and give them so much to read, but (they won't understand) until they see it and say, 'Wow, it really does exist.'"

Ragsdale gave students a 90-minute presentation on slavery and its lingering effects, followed by a Q&A session. After the program, she invited students to view several artifacts from her collection she had laid out on tables at the head of the school's auditorium.

Among the objects Ragsdale displayed at the program were 20th-century product advertisements depicting popular African-American caricatures, rusted iron shackles dating to slavery's heyday and a leather whip used for punishing misbehaving slaves. The thin whip, only a few feet in length, doesn't look too frightening at first glance, but Ragsdale insisted it was a violent and effective torture tool.

"It doesn't feel like much," she said, running her finger along one end. "But what they would do is soak it in salt water or brine, and it would become like a razor's edge."

Ragsdale's husband, J. Justin, began collecting slavery artifacts about 50 years ago, she said. The couple began their traveling exhibit - which has gone as far away as Bermuda - in the early '90s, and in the 2000s, established their physical museum in the Port Richmond section of Philadelphia.

Reece Tunstall, a 16-year-old sophomore in Robbins' English class, remained after the presentation to look over the artifacts. Among the most powerful in his eyes was Ragsdale's authentic Ku Klux Klan robe, which he said put racism into perspective.

"I see it always on TV, like the History Channel, but I never really saw one in person," Tunstall said.

Despite some obvious advances in race relations, aspects of racism in America still persist. The N-word, used often in African-American culture, is a symbol of black oppression Ragsdale would like to see eliminated from the vernacular, and the paddles used in hazing rituals are holdovers of slave torture, she said.

Slavery is a painful period of American history we might wish to forget, Ragsdale said, but it's one we can't if we're to learn from it.

"They don't know this part of their history, because it's not taught for the most part, and it's not talked about much in homes, black in particular," Ragsdale said. "This is not just black history. This is American history. Slavery was a dark and tragic period of American history, but American history nonetheless."

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