Superstition of the Serpent and the Emerald

"After having read in learned books of this peculiarity of the emerald, I tested it by my own experiment and found the statements exact. It chanced that I had in my possession a fine emerald of the zababi variety, and with this I decided to make the experiment on the eyes of a viper. Therefore, having made a bargain with a snake-charmer to procure me some vipers, as soon as I received them I selected one and placed it in a vessel. This being done, I took a stick of wood, attached to the end a piece of wax, and embedded my emerald in this. I then brought the emerald near to the viper's eyes. The reptile was strong and vigorous, and even raised its head out of the vessel, but as soon as I approached the emerald to its eyes, I heard a slight crepitation and saw that the eyes were protruding and dissolving into a humor. After this the viper was dazed and confused; I had expected that it would spring from the vessel, but it moved uneasily hither and thither, without knowing which way to turn; all its agility was lost, and its restless movements soon ceased."