Sails of Silver now sported the same line-up that had brought it to the height of its success, "Sails of Silver" has often been seen as embodying a different spirit from their classic albums of the 1970s. Prior to "Sails of Silver", the band had always performed songs written by other people, predominantly traditional songs, but also a few 20th century pieces, such as the two Brecht songs on "Storm Force Ten". But on this album they included several songs they had written themselves, including "Let Her Go Down" and "Senior Service". This was the beginning of a trend that continues down to
Forces on sails presented to windward and, therefore, there are two leaches. On sails attached to a mast and boom, these edges may be curved, when laid on a flat surface, to promote both horizontal and vertical curvature in the cross-section of the sail, once attached. The use of battens allows a sail have an arc of material on the leech, beyond a line drawn from the head to the clew, called the "roach". As with aircraft wings, the two dominant factors affecting sail efficiency are its planform—primarily sail width versus sail height, expressed as an aspect ratio—and cross-sectional curvature or draft. In