132 A HISTORY OF 



maruei prepare ihose flowers for making opium, are very sensibh 

 affected with the drowsiness they occasion. A physician of Mr. 

 Beyle's acquaintance, causing a large quantity of black hellebore to 

 be pounded in a mortar, most of the persons who were in the room, 

 and especially the person who pounded it, were purged by it, and some 

 of them strongly. He also gathered a certain plant in Ireland, which 

 the person who beat in a mortar, and the physician who was stand 

 ing near, were so strongly affected by, that their hands and faces 

 swelled to an enormous size, and continued tumid for a -ong time after 



But neither mineral nor vegetable steams are so dangerous to the 

 constitution, as those proceeding from animal substances, putrefying 

 either by disease or death. The effluvia that comes from diseased 

 bodies, propagate that frightful catalogue of disorders which are called 

 infectious. The parts which compose vegetable vapours and mineral 

 exhalations, seem gross and heavy, in comparison of these volatile 

 vapours, that go to great distances, and have been described as spread- 

 ing desolation over the whole earth. They fly every where ; pene- 

 trate every where ; and the vapours that fly from a single disease, 

 render it soon epidemic. 



The plague is the first upon the list in this class of human calami- 

 ties. From whence this scourge of man's presumption may have its 

 beginning, is not well known : but we well know that it is propagated 

 by infection. Whatever be the general state of the atmosphere, we 

 learn, from experience, that the noxious vapours, though but singly 

 introduced at first, taint the air by degrees ; every person infected 

 tends to add to the growing malignity ; and, as the disorder becomes 

 more general, the putrescence of the air becomes more noxious, so that 

 the symptoms are aggravated by continuance. When it is said that the 

 origin of this disorder is unknown, it implies, that the air seems to 

 be but little employed in first producing it. There are some coun- 

 tries, even in the midst of Africa, that we learn have never been 

 infected with it ; but continue, for centuries, unmolested. On the 

 contrary, there are others, that are generally visited once a year, as 

 in Egypt, which, nevertheless, seems peculiarly blessed with the se- 

 renity and temperature of its climate. In the former countries, which 

 are of vast extent, and many of them very populous, every thing 

 should seem to dispose the air to make the plague continual among 

 them. The great heats of the climate, the unwholesomeness of the 

 food, the sloth and dirt of the inhabitants, but, above all, the bloody 

 battles which are continually fought among them, after which heaps 

 of dead bodies are left unburied, and exposed to putrefaction. All 

 these one might think would be apt to bring the plague among them, 

 and yet, nevertheless, we are assured by Leo Africanus, that in Nu- 

 midia the plague is not known once in a hundred years ; and that in 

 Negioland, it is not known at all. This dreadful disorder, therefore, 

 must have its rise, not from any previous disposition of the air, but 

 from some particular cause, beginning with one individual, and ex 

 tending 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 yeai 

 1346, as we are told by Mezeray, was so contagious, that scarce a v' 



