NOVUM ORGANUM 125 



mit of Olympus was such, that those who ascended it were 

 obliged to carry sponges moistened with vinegar and water, 

 and to apply them now and then to their nostrils, as the air 

 was not dense enough for their respiration; on the summit 

 of which mountain it is also related, there reigned so great 

 a serenity and calm, free from rain, snow, or wind, that the 

 letters traced upon the ashes of the sacrifices on the altar of 

 Jupiter, by the fingers of those who had offered them, would 

 remain undisturbed till the next year. Those even, who at 

 this day go to the top of the Peak of Teneriffe, walk by 

 night and not in the daytime, and are advised and pressed 

 by their guides, as soon as the sun rises, to make haste in 

 tbeir descent, on account of the danger (apparently arising 

 from the rarity of the atmosphere), lest their breathing 

 should be relaxed and suffocated. 18 



The reflection of the solar rays in the polar regions is 

 found to be weak and inefficient in producing heat, so that 

 the Dutch, who wintered in Nova Zembla, and expected 

 that their vessel would be freed about the beginning of 

 July from the obstruction of the mass of ice which had 

 blocked it up, were disappointed and obliged to embark in 

 their boat. Hence the direct rays of the sun appear to have 

 but little power even on the plain, and when reflected, 

 unless they are multiplied and condensed, which takes place 

 when the sun tends more to the perpendicular; for, then, 

 the incidence of the rays occurs at more acute angles, so 

 that the reflected rays are nearer to each other, while, on 

 the contrary, when the sun is in a very oblique position, 



15 Bouguer, employed by Louis XIV. in philosophical researches, ascended 

 the Andes to discover the globular form of the earth, and published an account 

 of his passage, which verifies the statement of Bacon. 



