4 MONT BLANC. 



vapour suspended in the inferior regions of the air, deprived me of the 

 distinct view of the lowest and most remote objects, such as the plains of 

 France and Lombardy; but I did not so much regret this loss, since I 

 saw with remarkable clearness, what I principally wished to see, viz. 

 the assemblage of these high ridges, with the true forms and situations 

 of which I had long been desirous of becoming thoroughly acquainted. 

 I could scarcely believe my eyes I thought myself in a dream when I 

 saw below my feet so many majestic peaks, especially the Needles, the 

 Midi Argentiere, and Geant, whose bases had proved so difficult and 

 dangerous of access. 1 obtained a perfect knowledge of their proportion 

 to, and connexion with, each other; of their form and structure; and a 

 single view removed more doubts, and afforded more information, than 

 whole years of study. While I was thus employed, my guides pitched 

 my tent, and were fixing my apparatus for the experiments I had proposed 

 to make on boiling water, but when I came to dispose my instruments for 

 the purpose, I was obliged, almost at every instant, to desist from my 

 labours, and turn all my thoughts to the means of respiration. When it 

 is considered that the Mercury in the barometer was no higher than 16 

 inches and a line (17 145 inches English), and that this air had conse- 

 quently little more than half the density of that on the plains, the breathing 

 must necessarily be increased, in order to cause, in a given time, the 

 passage of a sufficient quantity of air through the lungs. The frequency 

 of respiration increased the circulation of the blood ; more especially as 

 the arteries on the surface of the body had not the pressure they were 

 usually accustomed to. We were all in a feverish state, as will be seen 

 in the sequel. While I remained perfectly still, I experienced but little 

 uneasiness, more than a slight oppression about my heart; but on the 

 smallest bodily exertion, or when I fixed my attention on any subject for 

 some minutes together, and particularly when I pressed my chest in the 

 act of stooping, I was obliged to rest, and pause for two or three minutes. 

 My guides were in a similar condition. We had no appetite, and our 

 provisions, which were all frozen, were not well calculated to excite it. 

 Nor had we any inclination for wine or brandy, which increased our 

 indisposition, most probably, by accelerating the circulation of the blood. 

 Nothing but fresh water relieved us, and much time and trouble were 

 necessary to procure this article, as we could have no other than melted 

 snow. I remained on the summit till half- past three, and though I did 

 not lose a single moment, I was not able to make all those experiments in 

 four hours and a half, which I have frequently done in less than three 

 hours by the sea-side. We returned much easier than I could have 



