From:  Edward Whymper in the Anthology of the Outdoor Experience (pp. 30-46).  In addition to the Anthology, the reading is found here:  Scrambles Reading. 

In Edward Whymper's book Scrambles Amongst the Alps, Whymper learns that Jean-Antoine Carrel has double-crossed him and will be attempting to climb the Matterhorn by the Italian Ridge.  Whymper is alarmed.  He quickly hikes over to Zermatt (on the Swizz side of the mountain)  to line up climbers for an attempt on the Hornli Ridge.  The location of the Matterhorn and both the Italian and Hornli routes on the mountain are illustrated below: