Samples of Albert Einstein's brain on display at the Mütter Museum

More than five decades after the brain of Albert Einstein was preserved, partitioned, and distributed to the private collections of various hospitals and researchers, a set of the precious samples is now on public display.

On Thursday, Lucy Rorke-Adams, a prominent neuropathologist at Children's Hospital of Philadelphia, donated 46 slides containing Einstein's gray matter to the Mütter Museum of the College of Physicians of Philadelphia.

"They are a very important part of medical history," said Rorke-Adams, 82, who received the slides from a colleague in the mid-1970s.

The ridges and valleys of this world-changing brain have held a certain popular fascination since the famous physicist died in 1955, perhaps all the more because the various samples have been out of the public eye. The brain has been the subject of a quirky documentary, a book, and a handful of research papers that sought to discern the physical underpinnings of Einstein's intellectual gifts.

By most accounts, the physician who performed the autopsy of Einstein's body, Thomas Harvey, removed the brain without permission but soon obtained the family's approval to keep it for scientific study.

Harvey, who died in 2007, kept most of the brain in his home, separated into three glass jars, and finally published a study of it in 1999. He later gave it to University Medical Center at Princeton, where he had performed the autopsy years earlier.

The slides donated by Rorke-Adams reveal a kind of medical artistry that has been lost to the past. Marta Keller, a technician at Philadelphia General Hospital, spent months slicing the tissue into thin sections so they could be preserved for posterity, Rorke-Adams said.

Some are stained to reveal individual brain cells, others to highlight the presence of myelin, the fatty material that acts as the brain's insulator. The intricate cerebral byways and undulations take on a chocolaty-brown hue when the vintage glass is held up to the light.

Robert D. Hicks, director of the Mütter Museum, said he welcomed the donation as an illustration of the scientific process.

"I'm particularly pleased that the samples were created specifically for scientific analysis," Hicks said. "If it was just a finger in a jar, that's just going to be a relic for people to come and gawk at." The slides are displayed in a wooden box behind a glass case, with one slide highlighted on a magnifying device.