THE EARTH. 281 



must have its rise, not from any previous disposi- 

 tion of the air, but from some particular cause, 

 beginning with one individual, and extending the 

 malignity, by communication, till at last the air 

 becomes actually tainted by the generality of the 

 infection. 



The plague which spread itself over the whole 

 world in the year 1346, as we are told by Meze- 

 ray, was so contagious, that scarcely a village, or 

 even a house, escaped being infected by it. Be- 

 fore it had reached Europe, it had been for two 

 years travelling from the great kingdom of Ca- 

 thay, where it began by a vapour most horridly 

 fetid ; this broke out of the earth like a subterra- 

 nean fire, and, upon the first instant of its erup- 

 tion, consumed and desolated above two hundred 

 leagues of that country, even to the trees and 

 stones. 



In that great plague which desolated the city 

 of London in the year 1665, a pious and learned 

 schoolmaster of Mr Boyle's acquaintance, who 

 ventured to stay in the city, and took upon him 

 the humane office of visiting the sick and the 

 dying who had been deserted by better physicians, 

 averred, that being once called to a poor woman 

 who had buried her children of the plague, he 

 found the room where she lay so little, that it 

 scarcely could hold any more than the bed 

 whereon she was stretched. However, in this 

 wretched abode, beside her, in an open coffin, 

 her husband lay, who had some time before died 

 of the same disease ; and whom she, poor crea- 

 ture, soon followed. But what showed the pecu- 



