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How Four Women Told The World About The Nazis’ Medical Experiments

In January of 1943, four Polish political prisoners in Ravensbrück, a women-only Nazi concentration camp in northern Germany, wrote letters to their families.

Inmates were allowed to write one letter per month, missives that the SS strictly censored. The four women escaped suspicion by banally describing life in the camps as pleasant. But in truth, the missives contained messages revealing atrocities perpetrated by SS physicians.

In 27 letters sent between 1943 and 1944, Krystyna Czyz, Wanda Wijtasik and the sisters Janina and Krystyna Iwaska implemented a code system and used urine as invisible ink to expose the conditions at Ravensbrück, where they were subjected to medical experimentation. David Gil’s forthcoming Hebrew-language book “The Art of Hiding,” previewed by Haaretz, explains how Czyz led her fellow inmates in the endeavor, which succeeded in broadcasting vital information about Nazi war crimes.

Czyz, who was 15 when the Nazis invaded her hometown of Lublin, Poland in September 1939, was a member of the Polish underground, working as a lookout and communications officer. Her involvement led to her arrest by the Gestapo in 1941, after which she was interrogated and tortured for half a year before being deported to Ravensbrück.

In the camp, she was among a group of at least 74 young Poles who, on the orders of Heinreich Himmler’s personal doctor, Karl Gebhardt, were subjected to gashes on their legs with shards of wood and glass. The SS doctors, who began their Ravensbrück experiments in the summer of 1942, then introduced bacteria to the women’s open wounds with the goal of testing prototypes of anti-infection medication.

Called “rabbits” by the SS, Czyz and her friends decided in January 1943 to report their treatment to the outside world. Czyz hoped her parents, who were members of a Polish underground cell that taught children after the Polish schools were shut down, would be able to spread the word of their plight to the Polish underground.

The women decided to write the coded messages in urine, which goes invisible when it dries, but can appear again when exposed to heat.

Czyz devised a clever way to get her family to examine her first coded letter closely for hidden clues: In the letter, she referenced the Polish book “Satan from the Seventh Grade,” in which a seventh-grader named Adam hides messages to his friend through the use of acrostics while imprisoned in a cellar. Czyz’s brother suspected she mentioned the book because she too was hiding something, and discovered that Czyz wrote “list moczem,” Polish for “letter in urine,” by an acrostic method. Czyz’s mother then exposed the letter to a hot iron to reveal the invisible message in the margins: “We have decided to tell the whole truth,” the letter began.

The letter described the medical experiments, told the family to expect more letters like it and instructed them to confirm they had read the hidden text through the use of a code word. After the first round of letters Czyz and her friends managed to write more extensively by scribbling parts of a longer message in each of their letters. Their families would then meet in secret to reconstruct the entirety of the hidden text.

The letters would prove damning for the Nazi doctors, providing their names and the names and serial numbers of their victims, as well as the specifics of the procedures being performed.

In May of 1943, the letters were even used in the hopes of helping Ravensbrück inmates escape.

“Five female Polish political inmates have escaped,” Janina Iwaska wrote, in urine, to her father on an envelope, Haaretz reports. “We are preparing a new escape. Send in a parcel: a compass, an accurate map of Germany, two false identification documents with photographs that are not especially characteristic. As much Reichsmarks as possible and some jewelry (gold!)”

Iwaska asked her father to hide his response in a jar of jam and destroy her initial letter. It’s unclear if he followed through. But regardless of whether they succeeded in aiding escapes, the four women’s letters made an impact.

Czyz’s parents sent her messages to their contacts in the underground who managed to spread the letters to Warsaw, the Vatican, the Red Cross in Geneva and, pivotally, the Polish government in exile in London.

A London radio station owned by the Polish underground first reported on the Ravensbrück experiments on May 3, 1944.

“The women in [Ravensbrück] are being submitted to vivisection experiments and are being operated on like rabbits,” the broadcast said, as recorded in the book “Ravensbrück: Inside Hitler’s Concentration Camp for Women,” by Sarah Helm. “The [occupation] authorities have made lists of all women who had to submit to such operations. It is feared that these records are being kept for the purpose of murdering these women so as to obliterate all traces of their crimes.”

The announcement, intended specifically for the ears of the German authorities, went on to promise retribution: “None of the hired assassins of Ravensbrück will escape justice.”

After the war ended, Gebhardt was hanged as a result of the Nuremberg Doctors Trial. And 11 guards and warders from Ravensbrück, all female, were sentenced to death for war crimes and crimes against humanity. Their conviction was based in part on the evidence of the secret letters.

All four letter writers survived the war and went on to have families and careers. Wijtasik became a psychiatrist, Janina Iwaska became a journalist in Paris, her younger sister Krystyna Iwaska became a doctor and Czyz became a research fellow in geography at Maria Curie-Skłodowska university in Lublin, her home city, where her letters are now on display at the Martyr Museum.

PJ Grisar is the Forward’s culture intern. He can be reached at [email protected]

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