Excerpt from a letter by John H. Horn written in January 1945 (LOC archive):
Leo had been living and working under the name of Kading as a gentile for years, respected and honored by his boss and fellow workers – until October 1944. He confided in his always open and good-hearted manner to another Jew, Rachmann was his name his true identity. This Rachmann was an agent for the Gestapo. (He was later gassed too, as were all the other Jewish agents). Leo was at the time of his arrest in the Jewish Hospital in Iranische Srtasse. He was taken out in one of the periodic raids on a stretcher by the Gestapo. From the Sammellager in the Oranienburgerstrasse to Auschwitz was a one way road.
The curtain has fallen on one of the most inhuman and most horrible chapters of mankind, no eternity no power on earth can restore what has been destroyed. Leo, Luzie Arthur and family will never die, they cannot die, they are there, wherever I am, they are closer to me now, than they ever were. In their names I feel obligated to fight this war to a successful end, it is far from concluded. I know if they could speak they would want me to go on.
If we don’t remember the past, how can we do any better?