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
Beaufort scale law relating wind velocity to Beaufort force. Wave heights in the scale are for conditions in the open ocean, not along the shore. The wind speeds in different units are not mathematically equivalent; e.g. 12–19 km/h is not equivalent to 8–12 mph, and both are not equivalent to 7–10 knots. The reason is that the Beaufort scale is not an exact nor an objective scale. It was based on visual and subjective observation of a ship and of the sea. The corresponding integral wind speeds were determined later, but the values in different units were never made equivalent. The scale