Force Ten (song) worked with Rush on their song "Tom Sawyer", had sent Neil Peart some lyrics for the song, and Peart would add more verses to it. Lyrically, the song describes the "storms of life," making a reference to a very high level of the Beaufort scale ("force ten" is defined as a 'storm', being near the scale's maximum of 12) as an analogy, according to the book "Rush and Philosophy: Heart and Mind United". Musically, "Force Ten" is composed in A minor, with changes into A major scale occurring in the song. The song is set in common time at a
Fujita scale F1 corresponds to the twelfth level of the Beaufort scale, and F12 corresponds to Mach number 1.0. F0 was placed at a position specifying no damage (approximately the eighth level of the Beaufort scale), in analogy to how the Beaufort's zeroth level specifies little to no wind. From these wind speed numbers, qualitative descriptions of damage were made for each category of the Fujita scale, and then these descriptions were used to classify tornadoes. The diagram on the right illustrates the relationship between the Beaufort, Fujita, and Mach number scales. At the time Fujita derived the scale, little information was