“What’s in the box?” was the question many Philadelphians were asking this week after Penn Museum acquired a mysterious unopened suitcase from a vintage dealer in Kentucky. 

According to the museum’s Facebook page, the valise once belonged to Mary Louise Baker, an artist who worked at the museum from 1908 to 1936. 

“She was probably the best archeological illustrator of her time,” Penn Museum’s senior archivist Alessandro Pezzati told Philly.com

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Pezzati opened the suitcase, whose contents hadn’t seen the light of day in more than 50 years, during his weekly “Unearthed in the Archives” presentation on Friday via Facebook Live. 

So what was in the case, which was covered in stickers from Baker’s extensive travels?

After struggling with the its locks, whose keys no longer worked, Pezzati used a screwdriver and lifted the lid of Baker’s valise. 

Inside were an unused notebook, photo negatives of unidentified people, a news clipping from 1927 about one of her artistic endeavors and a letter she wrote during a stormy sail through the Mediterranean Sea to Israel in 1932.

“She traveled everywhere. … Nothing scared her. She was a remarkable woman,” Pezzati said. 

Baker, who was born in 1872, died in 1962. Her more-than-500 contributions to the museum included depictions of Maya pottery, 54 diaries, scrapbooks and a model of the Throne Room of Merenptah that can still be seen in its Egypt (Sphinx) Gallery.

Pezzati said he will use the scrapbooks to try and identify some of the people in the photo negatives.