ITS KPIZOOTIC FORM. 63 



M. Voisin, that, if the contagion can possibly be trans- 

 mitted from horses to men, it ought to be communi- 

 cated Avith gi'eater facihty from horses to sheep. These 

 suppositions offer a new field for investigation, which 

 experiments might elucidate*." 



Ovine variola early attracted attention from its ra- 

 vages as an epizootic ; and many of these outbreaks 

 are recorded. In our first Chapter we have described 

 one which occurred at Modena in 1691 ; and another 

 in Lower Hungary in 1712. This epizootic form of 

 the disease is also stated to have visited Picardy in 1746, 

 and to have continued till 1792, destroying hundreds 

 of sheep every year dm'ing that intervalf . Rabelais 

 and Joubert mention the existence of clavelee in France 

 in the sixteenth century, since which period many parts 

 of that country have witnessed great destruction among 

 the flocks, particularly in 1816. Hurtrel d'Arboval 

 affirms, that since it was first observed, it has been found 

 to return as an epizootic every ten or fifteen years ; and, 

 according to Captain Carr's account, it is well known in 

 Germany, where it often appears in different and widely 

 separated localities. These facts, while they shew the 

 absolute necessity for the adoption of vigorous measures 

 to guard against similar outbreaks in England, estabhsh 

 also an important resemblance between ovine and 

 human small-pox. 



The experiments which are recorded in these pages, 

 and likewise the rapid extension of the disorder among 

 the flocks of this country, prove very satisfactorily its 

 contagious nature ; it is, therefore, unnecessary to add 



* Dictionnaire de Medecine Veterinaire, article Clavelee, vol. i, 

 p. 451. 



t See pp. 9 and 12. 



