On February 8, 1812, Ludwig Beethoven writes to Nikolaus Zmeskall (1759-1833), who is one of his few close personal friends in Vienna. Zmeskall was an official in the Hungarian Chancellery. The letter reads:
Most extraordinary and first and foremost man of the pendulum in the world, and without lever too! ! ! ! I am much indebted to you for having imparted to me some share of your motive power [buoyancy]. I wish to express my gratitude in person, and therefore invite you this morning to come to the "Swan,"- a tavern, the name of which itself shows that it is a fitting place when such a subject is in question,
Beethoven also writes to Josef de Varena that day. Part of his letter includes the following:
...As I do not publish any new work until a year after its composition, and, when I do so, am obliged invariably to give a written assurance to the publisher that no one is in possession of it, you can yourself perceive that I must carefully guard against any possible contingency or casualty as to these pieces....