Epidemics. 161 



It will be found that, taking the year 1817 as a starting 

 point for a new epidemic era, that about every 640 years 

 there* have been great epidemic changes or new forms of 

 disease introduced, or old ones revived and spread over wider 

 areas. Take the era from 1177 to 1817 as the last period. 

 True plague shortly after this period or in 1217 visits Italy ; 

 1222 Egypt, France, and Germany. In 1252 it visits 

 England ; 1347 this country is again visited, Italy again in 

 1477 ; but from 1517 till 1666 it was visiting all the great 

 Continental towns, and from thence travelled into the sur- 

 rounding countries, and from time to time paid a visit to this 

 country, no country appearing to escape its awful calamities 

 Spain, Germany, France, the Netherlands, Italy, and 

 many other lands, venting its last fury in this country in 

 1666. From this time it ceased in our land, but it returned 

 to its native place in and about the Levant by way of 

 Dresden, Dantzic, and Marseilles in 1720, Vienna and Hun- 

 gary 1722, Moscow 1772, Egypt and Constantinople between 

 1778 and 1792 ; but since 1772 it has lingered much in 

 Egypt and Asia Minor, where it still lingers, and often 

 breaks out in a destructive manner in and about the locality 

 of its first centre or endemic area. 



Small-pox first appeared in England about the year 1174, 

 or three years earlier than the fixed period, 1177. It was 

 general throughout Europe in 1436, and in 1638 it got to 

 America. If it came to England in 1174 it must have passed 

 through France first, for it had been long before in Spain. 

 Its widest diffusion and greatest mortality appear to have been 

 attained in the seventeenth century, but at all times since its 

 appearance north of the Apennines it has been a most fatal 

 disease, breaking out in special parts in great severity until 

 its arm of destruction was mutilated and impeded by vaccina- 

 tion. The years 1870 and 1871 would perhaps have seen 

 as widespread destruction from this plague, as from any 



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