OF SERPENTS. IO7 



by the refpe£lable authority of Dr. Mead, obferving 

 how quickly death foinetimes follows the bites of 

 ferpents, concluded that the venom could a6l through 

 the medium of the nerves only. This is one of thofe 

 vague conje6tures which has ferved, at one time or 

 another, to obftruft the progrefs of every fcience, and 

 which owes its reputation to a fort of readinefs in 

 explaining every thing, becaufe it can explain nothing 

 in an intelligible manner. The celebrated Italian. 

 naturalift, Fontana, has freed us from this difficulty, 

 by demonftrating, from a great variety of experiments 

 on different animals, that the venom of the viper is 

 perfectly innocent when applied to the nerves only ; 

 that it produces in them no fenfible change, and that 

 they are incapable of conveying the poifon to the ani- 

 mal. On the other hand, he has fliewn in a very dif- 

 tin6t manner, that it a6ls immediately upon the blood, 

 that through the medium of this fluid, it deftroys the 

 irritability of the mufcular fibres, and produces death. 

 Neither is it difficult, upon this view of the fubjeft, to 

 underftand how the poifon may fometimes produce 

 very fudden death ; for if this aclive matter happen 

 to be thrown immediately into a large vein running 

 along the furface of the body, it will more readily be 

 carried to the vital parts, and may render the ufe of 

 the moft powerful remedies ineffectual. 



The ground being fo far cleared, the queftion now 

 occurs, what is the peculiar quality in the venom, 

 which enables it to produce fuch direful effe6i:s? Till 

 we can anfwer this queftion in a fatisfaftory manner, 

 it is evident, that the praftice in this difeafe muft be 

 guided by chance, and we can entertain no rational 

 hope of correfting the poifon. It is not many years fmce 

 this fubjeftfeemed to be covered with an impenetrable 

 veil, and Fontana., among all his reafonings upon 

 the poifon of the viper, does not once attempt to 

 remove it. It is therefore an agreeable reiie61ion, that 

 the rapid progrefs which chemiftry has made of late 



vears, 



I 



