192 TRAVELS AMONGST THE GREAT ANDES, chap. x. 



It appears from a passage in the Comptes Rendus (vol. Ixxxviii., 

 p. 1241) ^ that Boiissingault was affected on Antisana by snow- 

 blindness, and I had a similar unpleasant experience on the 7th of 

 March. Though the harm was done between 11 a.m. and 1 p.m. 

 (through uncovering the eyes to use my field-glass), it did not 

 manifest itself for some hours later. In the course of the even- 

 ing I became unable to see, and remained in that condition for 

 twenty-four hours. Verity sat up through the night handing 

 rags dipped in a solution of sulphate of zinc, changing them 

 when they grew hot, and this occurred in a few minutes after 

 each application. 



The affection that is termed ' snow-blindness ^ is inflammation 

 of the eyes. They become extraordinarily sensitive to light. The 

 lids refuse to open ; tears come freely, and coagulating round the 

 lashes glue the lids fast. To apply a lotion effectively, the lids 

 must be forced open, and the instant this is done the patient will 

 imagine that red-hot needles are being driven through the eyes 

 into the brain. The pain is acute, and sometimes makes strong 

 men howl.*^ 



Snow-blindness has long been known to Indians dwelling • in 

 the Andes. Acosta, writing three centuries ago, mentions a remedy 

 that they applied, which reminds one of the raw beefsteaks used 

 by prize-fighters. 



^ " Pendant mon ascension, je fus atteint subitement d'une ophthalmie des plus 

 graves, causee par la reverberation des neiges. Oblige de retourner a Quito, je dus 

 renoncer a continuer les observations que j'avais commenc6es a la m6tairie." 



2 Medical men recommend two or three grains of sulphate of zinc to an ounce of 

 water. In practice, I find that the solution may be made stronger, with safety and 

 benefit, and that six, eight or ten grains to the ounce is not too much to use. 

 Although the inflammation may be reduced quickly, and the absolute inability to 

 see may soon pass away, the eyes remain tender and weak for a long time (after a 

 bad attack, even for weeks or months) and they are more liable to be affected than 

 before, unless extra precautions are taken. 



PuflSng and cracking of the skin, and snow-blindness, can be avoided by keeping 

 the face covered, and by using tinted snow-spectacles. My usual appearance at 

 great elevations on this journey is shewn at p. 80. 



