RED VAPOURS AT NIGHT. 89 



ran away, and they pursued him through the thorny cac- 

 tuses. At length, tired out, he took shelter in a cow-house, 

 whence he suffered himself to be quietly led to prison, 



Bonpland was seized with fever during the night; 

 but being endowed with great energy and fortitude he 

 continued his labours the next da v. The stroke of the 

 club had extended to the top of his head, and he felt its 

 effect for the space of two or three months. When 

 stooping to collect plants, he was sometimes seized with 

 giddiness, which led him to fear that an internal abscess 

 was forming. Happily these apprehensions were un- 

 founded, and the symptoms gradually disappeared. 



During a few- days which preceded and followed the 

 eclipse of the sun, very remarkable atmospherical phe- 

 nomena were observable. From the 10th of October to 

 the 3rd of November, at nightfall, a reddish vapour 

 arose in the horizon, and covered, in a few minutes, with 

 a veil more or less thick, the azure vault of the sky. 

 Sometimes, in the midst of the night, the vapours disap- 

 peared in an instant ; and at the moment when Humboldt 

 had arranged his instruments, clouds of brilliant white- 

 ness collected at the zenith, and extended towards the 

 horizon. On the 18th of October these clouds were so 

 remarkably transparent, that they did not hide stars even 

 of the fourth magnitude. He could distinguish so per- 

 fectly the spots of the moon, that it might have been sup- 

 posed its disk was before the clouds. 



After the 28th of October, the reddish mist became 

 thicker than it had previously been. The heat of the 

 nights seemed stifling, though the thermometer rose only 

 to 78°. The breeze, which generally refreshed the air 

 from eight or nine o'clock in the evening, was no longer 



