On 25 December 1887, Werner von Siemens wrote a letter to his brother Carl. The Siemens Historical Institute calls it the most important of his many letters. Siemens wrote that he saw the business only secondarily as a financial asset. For him it was ein Reich welches ich gegründet habe, an empire that he had founded. He wanted to hand it on undiminished to his descendants, so that they could continue to build in it. As early as 1863, he had written to Carl about founding eine dauernde Firma, a lasting firm.