168 Letter from M. Humboldt to C, Delamhres, 



at Quito, where we learned that captain Baudin had pur* 

 sued his voyage from west to cast bv the Cape of Good 

 Hope. Accustomed to misfortunes, we consoled ourselves 

 with the idea of having made so great sacrifices for an in-r 

 tention of doing good : casting our eyes on our herhals, our 

 baroiTietric and geodesic measurements, our drawings, and 

 our experiments on the air of the Cordillera, we did not 

 regret pur having traversed that country, a great part of 

 which has never been visited by any naturalists. We were 

 sensible that man ought never to depend on any thing but 

 what is produced hy his own energy. The province of 

 Quito, the highest land in the world, and torn by the grand 

 catastrophe of the 4th of February 1797, furnished us with 

 a vast Held for physical observations, \^olcanocs so enor- 

 mous, the l^ames of vyhich often rise to the height of oOO 

 toiscs, have never been able to produce a drop of liquid 

 lava ; they vomit up fire, sulphurous hydrogen gas, mud, 

 and carbonated argil. Since 1797 this whole part of the 

 world has been in agitation ; we every moment experience 

 frightful shocks, and the subterranean noise in the plains 

 of Rio Bamba resembles that of a mountain crunibling 

 to pieces under our feet. The atmospheric air and moist 

 tned earth (all these volcanoes are in decomposed porphyry 

 appear to be the grand agents of these combustions ad 

 these subterrajiean fermentations. 



It has hitherto been believed at Quito that 2470 tO'CS 

 IS the greatest height z,i which ipen could resist the r;ity 

 of the air. In the month of March 1 802 we spent pme 

 days in the l^rge plains v/hich surround the volcano ofA.n- 

 tisana at 2107 fathoms, wher-e the oxen, when huted, 

 often vomit up b}ood. On the l6th qf March we ouncj 

 out a passage over |:he snqw, a gentle acclivity, on-vhich 

 we ascended to the height of 2773 toises. The ai there 

 contained 0-0Q8 of parbonip acid, 0-218 of oxygep, and 

 0*774 of azote, Reauijiur's thermometer ^yas only <■ 1^"» 

 it was not ^.t all cold, but the bloqd issued from ovu" Ips a"d_ 

 eyes. The situation did not perjnit me tp make atrial of 

 Borda's compass but in a grpt{.o lower down at tht height 

 of 2467 toises ; the intensity of the magnetic foices vas 

 greater at that height than at Qujtp in t]ie ratip of 23C to 

 218: but it must not be forgotten tiiat the nvimber of oscil^ 

 lations often increases vvhen the inclination decreases, uid 

 that this intensity is increased by the mass of the nipuntiin, 

 the porphyry of which affects the magnet. In the expedi- 

 tion I undertook on the 23d of June 1 802 to Chimboiazo, 

 we proved that with patience it is possible to susum a, 

 .• ' greater 



