This book describes his subsequent expedition to Ecuador, designed primarily to collect data for the study of mountain sickness and of the physical effects of altitude. During 1880 Whymper twice ascended the previously unclimbed Chimborazo, the highest mountain in Ecuador and once considered the highest mountain in the world. (And ironically it is the highest mountain in the world if you measure from the center of the Earth, as it is near the Equator and the Earth bulges at the Equator!)

He also spent a night on the summit of Cotopaxi, and made first ascents of half-a-dozen other great peaks. In 1892 he published the results of his journey in Travels amongst the Great Andes of the Equator. The publication of this work was recognized by the Royal Geographical Society who awarded him Patrons medal.

Twenty-three years after his triumphant and disastrous conquest of the Matterhorn, Whymper turned his attention to the soaring Andes peaks of Ecuador. As DNB states, 'From a climber's point of view the expedition was completely successful. The summits of Chimborazo (20,948 feet) and six other mountains between 15,000 and 20,000 feet were reached for the first time. A night was spent on the top of Cotopaxi (19,613 feet), and the features of that great volcano were thoroughly studied. From the wider points of view of the geographer, the geologist, and the general traveller, Whymper brought home much valuable material, which was carefully condensed and embodied in [this book].'

Jill Neate states that 'This book was the first of the few great mountaineering classics of South American mountaineering literature. It remains essential reading for anyone visiting Ecuador.' Whymper was also one of the leading wood-engravers of his time and engraved the many superb illustrations in these volumes.

One of the ostensible reasons for this expedition was to scientifically investigate mountain-sickness. His findings and conclusions were correct as to its cause, and his suggestions for improving the unreliable aneroid barometer. For this work Whymper was awarded the Royal Geographical Societys highest honor, the 'Patron's Medal'.

From the Introduction: 

''It will be within the knowledge of most of those who take up this book that it has long been much debated whether human life can be sustained at great altitudes above the level of the sea in such a manner as will permit of the accomplishment of useful work. The most opposite statements and opinions have been advanced concerning this matter. The extremes range from saying that fatal results may occur, and have occurred, from some obscure cause, at comparatively moderate elevations, down to that no effects whatever have been experienced at the greatest heights which have been attained.

''Allegations of the latter class may be set aside for the present, for the evidence is overwhelming that, from 14,000 feet above the level of the sea and upwards, serious inconveniences have occurred; that prostration ( amounting in the more extreme cases to incapacitation has been experienced; and that, in some instances, perhaps, even death has resulted through some cause which operates at great elevations.....''

Contents include: from London to Guaranda; from Guaranda to the first camp on Chimborazo; the first ascent of Chimborazo; from Chuquipoquio to Ambato, Latacunga and Machachi; on an ascent of Corazon, and walks in the lanes of Machachi; on Cotopaxi and Illiniza; the ascent of Cotopaxi, and a night on the summit; the first ascent of Sinchoolagua; on Quito and the Quitonians; the first ascent of Antisana; upon an ascent of Pichincha; the first ascent of Cyambe; the first ascent of Sara-Urcu; on the province of Imbabura, and the first ascent of Cotocachi; a visit to the Pyramids of Quito; upon a walk on the Quito Road, and a journey to Altar; the first ascent of Carihuairazo; etc. etc.

Illustrations include: Chimborazo, from the Slopes above Guaranda; Chimborazo, from a little above the third camp; ice-cliffs under the summits of Chimborazo; carried on the litter into Ambato; Cotopaxi ( 19,613 feet ), from the Hacienda of S. Rosario; part of the interior of the Crater of Cotopaxi; Antisana ( 19,335 feet ), seen from the Hacienda; at samp on the Equator, at Corredor Machai; etc. etc.