'Principles of War' by Carl von Clausewitz
From the introduction to this translation of 'Principles':
...Before Clausewitz left Prussia in 1812 to join the Russian army and resist Napoleon, he prepared an essay on war to leave with the sixteen year-old Prussian Crown Prince Friedrich Wilhelm (later King Friedrich Wilhelm IV, r.1840-1858), whose military tutor he had become in 1810. This essay was called "The most important principles of the art of war to complete my course of instruction for his Royal Highness the Crown Prince" ["Die wichtigsten Grundsätze des Kriegführens zur Ergänzung meines Unterrichts bei Sr. Königlichen Hoheit dem Kronprinzen"]. This essay is usually referred to as the "Principles of War." It represented Clausewitz's theoretical development up to that point, translated into a form suitable for his young student. Unfortunately, it has often been treated as a summary of Clausewitz's mature theory—which it most emphatically is not. Rather, it is only a primitive precursor to his later magnum opus—On War. Its subject matter is largely tactical. While some of the more important theoretical concepts of 'On War' are fairly well-developed ("friction," for example), many are embryonic and others entirely absent. In particular, and in great contrast to the later work, "Principles of War" is not notably sophisticated in historical terms. It is based almost entirely on the experience of Frederick the Great and the wars with revolutionary France and Napoleon prior to 1812.
The translation reproduced here was done by Hans Gatzke in 1942. A German protestant, Gatzke (1915-87) emigrated to America in 1937. He graduated from Williams College in 1938 and got his master's degree from Harvard the following year. He then taught at Harvard, ultimately receiving his doctorate there in 1947. From 1944 to 1946, however, he was a second lieutenant in the U.S. Army, serving with Supreme Headquarters Allied Expeditionary Forces (SHAEF). He taught at Johns Hopkins from 1947 to 1964 and then moved to Yale...
A little light reading for the first weekend of spring...
By the way, if you have nice weather where you are, it might be a good idea to go and confirm your zero.
Just a suggestion.