Lamarck was first to classify clouds in a simple way at the start of the 19th century, but Luke Howard, a businessman, later put them into �types' such as stratus, cirrus and so on. This system was developed and became the International Cloud Atlas, a version of which was published in 1896. In that, there were ten cloud types and Cloud 9 was the white, fluffy, cottonwool-like sort angels are usually portrayed playing harps on! In that way, being "on cloud nine" meant floating free, in a sort of paradise, on a soft white cushion with not a care in the world.