VIPER. 91 
though as yet they had no manner of fangs that we 
could find, even with the help of our glasses.” 
The apparatus with which the viper gives the 
deadly wound, consists, as in other poisonous ser- 
pents, of two teeth or fangs seated in the upper 
jaw. These teeth are moveable, and are generally 
laid flat along the jaw ; but whenever the animal is 
inclined to bite they are instantly erected, and ready 
to inflict the mortal wound. Each fang is hollow 
throughout its length, and the lower end of the 
canal opens into a little bladder of venom, situated 
under the muscle of the upper jaw : when this 
muscle is put in action it compresses the bladder, 
and forces the poison through the tooth into the 
wound. 
From the experiments of Francini, related in the 
Philosophical Transactions, we learn that the venom 
of the viper is quickly fatal to small animals. Two 
pigeons were wounded by the fangs of a viper, 
whose head had been previously cut off. The 
wound was made by thrusting the fangs into the 
fleshy part of the pigeon’s breast, and pressing the 
poison through them from the bladders where it is 
secreted. The pigeon thus bitten began to stagger 
immediately, and died in a few minutes. The se- 
cond was wounded in the same part and expired in 
the same manner, but was rather longer in dying. 
A viper was then irritated so as to bite a cock in 
both his thighs ; in consequence of which he died 
in a quarter of an hour. These experiments were 
repeated, and others tried with a similar result, so 
