Commissioner of Agriculture 2fi3 



EARLY HISTORY 



This plague, like most of the animal pests of Europe, has mani- 

 festly prevailed from time immemorial in certain parts of Asia, 

 from which at intervals it extended westward as military necessi- 

 ties or racial emigration led to the movement of live stock from 

 such early Asian centers. Various obstacles tended, however, to 

 restrict this advance. From the infected eastern ranges, the live 

 stock could be moved only by road and on foot. Even this slow 

 mode of progress was further delayed by the necessity of stopping 

 daily for pasturage on the way. A drive of 1,000 to 3,000 miles 

 at 10 miles a day, even if it proceeded uninterruptedly, would 

 consume 100 to 300 days, and this, added to dangers from robbers 

 and the certainty of blackmail for the right of passage, virtually 

 forbade an European outlet and market to the stock owners of 

 central Asia. If these were insufficient as a deterrent, there re- 

 mained the obstacles of the Black Sea, the Sea of Azov, the Sea of 

 Marmora, the iEgean Sea and the Mediterranean, the mountain 

 ranges of the Caucasus, Ural and Altai, the great desert of 

 northern Turkestan, and the interminable steppes of southern 

 Siberia and Russia. 



The duration of the foot and mouth disease is about 1-4 days 

 and in 7 days more the attendant wounds are practically healed, 

 so that the animal may usually be considered safe, apart from the 

 infection laid up in the buildings or attached to the surface -of 

 the body. 



Paradoxical as it seems at first thought, it may be held that 

 the extreme contagiousness of the disease and its short duration 

 acted to a considerable extent on snch long journeys as obstacles 

 to a distant propagation of infection. Once introduced into a 

 moving herd, it attacked every animal within a week; within a 

 fortnight, all passed through it and were well on the way to re- 

 covery. The herd would have to be rested a few days at least, 

 when fasting, sick and lame, so that the area of contamination 

 was relatively more restricted ; when again started they would be 

 in no condition to diffuse so much virus along their trail, and this 

 would soon cease altogether. Then, as the whole drove had been 

 already affected, there was no susceptible animal left to develop 

 the active disease later, and to scatter in fed inn along their future 



