108 Professor Thomas B. Fraser [March 20, 



ferments, and have no power of reproducing themselves in the body, 

 but they are substances that produce effects having a direct relation- 

 ship to the quantity introduced into the body. This quantity in the 

 case of each serpent varies with its size and bodily and mental 

 condition ; with the nature of the bite — whether both fangs or only 

 one has been introduced, whether they have penetrated deeply or 

 only scratched the surface ; and with other circumstances related to 

 the serpent, such as whether it had recently bitten an animal or not, 

 and thus parted with a portion or retained the whole of the venom 

 stored in the poison glands. 



A bite may, therefore, result in very little danger, or it may be 

 rapidly fatal ; but, in order to produce death, there must have been 

 introduced into the tissues at least a certain quantity of venom, which 

 is spoken of as the minimum-lethal quantity or dose. The minimum- 

 letbal quantity for the animal bitten, again, is different for different 

 species of animals, and different also for different individuals of the 

 same species, the chief cause of difference between adult animals of 

 the same species being the body weight of the individual, the quantity 

 required to produce death being very exactly related to each pound 

 or kilogramme of weight. 



If even a minute fraction below the minimum-lethal has been 

 introduced into the tissues by an effective bite, death will not follow, 

 although serious and alarming symptoms will be produced of exactly 

 the same kind as those which follow a bite which terminates fatally. 



How then can we be assured, in any case of snake-bite in man, 

 that a quantity of venom sufficient to produce death has been intro- 

 duced ? It is impossible to answer this question except by the result. 

 If a quantity less than the minimum-lethal has been introduced, 

 although the gravest symptoms may be produced, the patient will 

 recover, whatever remedies are administered, provided, obviously, that 

 the remedies have not been so injudiciously selected or used that they 

 themselves, and not the insufficient quantity of venom, produce a 

 fatal termination. The recovery of a patient after the introduction 

 of less than the smallest quantity of venom capable of producing 

 death, has thus too often been attributed to the remedies that have 

 been administered ; and, consequently, as, indeed, is exemplified in 

 the treatment of many diseases, a large number of substances have 

 acquired an unjust reputation as antidotes. The list of antidotes has, 

 accordingly, become a very large one; but when their pretensions 

 have been subjected to sufficient tests, the verdict is that all of 

 them are valueless to prevent death when even the smallest quantity 

 of venom required to produce death has been received by an animal. 



Without entering into details, I will content myself with re- 

 producing the opinion of Sir Joseph Fayrer, that, " after long and 

 repeated observations in India, and subsequently in England, I am 

 forced to the conclusion that all the remedies hitherto regarded as 

 antidotes are absolutely without any specific effect on the condition 

 produced by the poison." 



But while medical practice and science, in each period of its 



