In 1841 James David Forbes, professor of natural philosophy at the University of Edinburgh, came to see the Matterhorn. A philosopher and geologist, and an observant traveller, he continued the work of De Saussure in his journeys and his writings. He was full of admiration for the Matterhorn, calling it the most wonderful peak in the Alps, unsealed and unscalable. These words, pronounced by a man noted among all his contemporaries for his thorough knowledge of mountains, show what men's feelings then were towards the Matterhorn, and how at a time when the idea of Alpine exploration was gaining ground in their minds, the Matterhorn stood by itself as a mountain apart, of whose conquest it was vain even to dream. And such it remained till long after this; as such it was described by John Ball twenty years later in his celebrated guide-book. Forbes ascended the Theodul Pass in 1842, climbed the Breithorn, and came down to Breuil; as he descended from the savage scenery of the Matterhorn, the Italian landscapes of the Valtournanche seemed to him like paradise. Meanwhile Gottlieb Samuel Studer, the geographer, together with Melchior Ulrich, was describing and mapping the topographical features of the Zermatt peaks.