1858.] Astronomical Rcperiment on the Peak of Teneriffe, 495 



The morning was desperately cloudy, quite a desponding sort 

 of day; but the angle of ascent in the road was happily most 

 moderate and uniform, so on and up we rode with the greatest 

 facility. A sympiesometer, by Adie of Edinburgh, gave the 

 heights without dismounting. At 3000 feet of altitude, still 

 pacing up a constant slope, the level of the clouds was reached, 

 — those clouds which had made the sky look so unhappy when we 

 were starting from the port of Orotava. A whiff or two of damp 

 mist flew about us for a while, and then we suddenly emerged into 

 clear hot sunshine. From that moment, and hour after hour, as 

 the decreasing column of the sympiesometer chronicled the height 

 ascended, and as we continued toiling up the long slope of the 

 mountain, the sun shone vehemently down upon us from a sky of the 

 purest blue ; and never did the clouds below attempt to leave their 

 constant level of 3000 or 4000 feet above the sea. In this bril- 

 liant illumination, in the rarefied and arid air, amidst volcanic 

 rocks of grotesque and imposing forms, — in fact, in this most moon- 

 like region we travelled on, until by evening we had reached the 

 top of Mount Guajara, on the southern side of the elevation crater ; 

 and thus within 24 days of leaving England, had the satisfaction of 

 bivouacking on the top of a mountain 8900 feet high, and only 28** 

 from the equator ; in a calm air, too, with a temperature of 65^, 

 and under a sky undimmed by a single cloud, and gloriously re- 

 splendent with stars. 



AVas not that at once a realisation of Newton's prophetic de- 

 scription, " a serene and quiet air on the top of the highest moun- 

 tains above the grosser clouds" ? — for all this time the lowlands 

 beneath us, and the sea far and wide, were covered in by a broad 

 expanse of mist, whose rollers were driving along under the in- 

 fluence of a violent N.E. wind. 



That great plain of vapour floating in mid-air at a height of 

 4000 feet, was a separater of many things. Beneath, were a moist 

 atmosphere, fruits, and gardens, and the abodes of men ; above, 

 an air inconceivably dry, in which the bare bones of the great 

 mountain lay oxidising in all variety of brilliant colours, in the 

 light of the sun by day, and stars innumerable at night. 



Below that constant curtain of cloud, were towns and villages, 

 — prisons, theatres and churches many, — above it, save a few goat- 

 herds wandering over the heights with their flocks of Guaiiche 

 breed, were no traces of human life but in our little astronomical 

 encampment. 



Then how truly serene and quiet, and transparent, too, was the 

 air above our 8900 foot elevation ; for, on erecting our telescopes, 

 not only was each star, whether high or low, seen with an exquisite 

 little disc and nearly perfect rings, but the space-penetrating power 

 was extended with tlie same instrument and same eye from the 

 10th magnitude, at the sea level, to the 1 4th, on Guajara. 



Similar results in their ultimate bearing, followed other obser- 



2m2 



