Holocaust Survivor, Who Hid in a Sewer, Headed U.S. Tech Firm

In early April 1945, with Nazi Germany nearing collapse, that optimism was put to a severe test. All Jews in the camp were ordered to gather for a roll call. The young man suspected some kind of atrocity awaited them.

He sought advice from an older prisoner, Erwin Lippmann, who had become his unofficial guardian. Mr. Lippmann steered Carl and his younger brother into a sewer, where they hid for a day or two.

Within days, U.S. troops liberated Buchenwald. Carl Rosner found his way to Sweden and in 1952 emigrated to the U.S., where he worked as a research engineer at General Electric Co. and for three decades headed Intermagnetics General Corp., which supplied materials for magnetic resonance imaging, or MRI, equipment.

Mr. Rosner died April 16 at his home in Niskayuna, N.Y. He was 93.

Karl Heinz Rosner, the first of three sons, was born April 4, 1929, in Hamburg. (He later changed the spelling of his first name to Carl.) His mother, Rahel Rosner, ran a bedding store with help from his Romanian-born father. His parents divorced, and his mother sought ways to emigrate with her sons as Nazi persecution of Jews increased. The youngest son, Eliot, was sent to Sweden as part of the Kindertransport program. Ms. Rosner followed him there, leaving 9-year-old Carl and his 8-year-old brother, Joseph Wolfgang, to live in an orphanage while awaiting a chance to emigrate.

“As a child you accept things,” Carl Rosner said in a 1997 interview with the Shoah Foundation. “You don’t question everything or worry about everything.”

In public, the boys had to wear star-shaped patches identifying themselves as Jews. In 1942, his Jewish school was closed, leaving Carl to play chess and read books in the orphanage. Other Jewish children were sent to concentration camps. At first, he felt left out and wanted to go with his friends.

His Romanian citizenship, a legacy of his father, saved him from that fate for a time. He and Joseph were moved to a Jewish old-age home, where they helped with kitchen chores. Later, they moved in with a family whose daughter had been sent to England.

They survived bombing raids in Hamburg but in June 1944 were arrested and sent to Buchenwald. Their heads were shaved. They were hosed with disinfectant. They were required to watch hangings of prisoners who tried to escape.

Carl Rosner was put to work making bricks and fell gravely ill from the starvation diet and freezing temperatures. He survived with luck and help from Mr. Lippmann.

In the fall of 1945, the Rosner brothers finally reached Sweden, and Carl Rosner resumed his formal education. He married another Holocaust survivor, Frieda Zeidshnur, and in 1952 they emigrated to Newark, N.J., where Mr. Rosner earned a degree at the Newark College of Engineering.

In 1955, GE hired him to work at a research lab in Schenectady, N.Y., where he helped develop superconducting magnets. In visits to grade schools, he spilled metallic shavings and then amazed the pupils by cleaning up the mess instantly with magnets.

He became chairman of a GE spinoff, Intermagnetics, in 1971. Mr. Rosner stepped down as chief executive in 1999 and retired as chairman three years later.

Philips Electronics

NV agreed to buy Intermagnetics for $1.3 billion in 2006.

By then, Mr. Rosner was running another company, CardioMag Imaging Inc., that developed technology for early detection of heart disease.

He was wary of retirement. He had noticed what happened to some people who give up work: “Suddenly, they drop dead.”

His wife, Frieda Rosner, died in 2000. He is survived by his brother Joseph, three children, six grandchildren and one great grandchild.

His daughter Elizabeth Rosner wrote a 2017 book, “Survivor Café,” exploring how the trauma of atrocities is passed on to new generations. In her case, she believes her father’s ordeals gave her a “tendency to be hyper-vigilant” and “see calamities around the bend.” It also gave her confidence that she could endure hardship.

“My father often talked about his luck in surviving,” she said. “He was reluctant to credit himself.” He was surprised when people considered him extraordinary.

Though he barely had a childhood, he learned late in life to clown around with his grandchildren. He loved chess and revered Beethoven. At home, his bookshelves were packed two books deep. “I want to know everything,” he told the Albany Times Union. “I’m interested in everything.”

Write to James R. Hagerty at [email protected]