Norwood's system of navigation: [electronic resource] : teaching the whole art, in a way more familiar, easie, and practical, than hath been hitherto done. Shewing, the projection of the plain scale: the sphere in plaino: astronomical problems useful in navigation: traverse tables: right lin'd triangles ... The description and use of a new instrument called encyclologium, or the sliding cirlces: which, with ease, resolves all questions of proportion, trigonometry, arithmetick, square and cube root, gunnery, mesuration and dyalling / by Matthew Norwood, teacher of mathematical arts.