HOSACK ON THE LAWS OP CONTAGION. 205 



had the disease in its mildest form, what he denominates the first degree, 

 in which the fever was slight, and the patient easily and promptly cured. 

 Dr. Desgenettes adds, that it was an imperfect experiment, and that it 

 does not disprove the communication of the disease by contagion, and 

 that he made the experiment for the purpose of quieting the fears of 

 the French troops, and of inspiring them with confidence.* 



But that the plague, in common with the other diseases I have asso- 

 ciated with it, is only communicable through the medium oflhi impure, 

 or vitiated atmosphere, is an opinion which, although it has never been 

 attended to by physicians, will be found to be verified by every writer 

 on this disease. The plague of Athens, the first of which we have any 

 authentic or satisfactory account, furnishes evidence of this truth. Whe- 

 ther that disease originated in the city of Athens, or was introduced 

 into it from ^Ethiopia, the fact is established, that, the circumstances 

 under which it appeared in that city were peculiarly favourable to its 

 diffusion. It appeared, according to Thucydides, in the beginning of 

 the summer season, and first of all at the Piraeus, the port and harbour 

 of Athens, from whence it spread with increasing mortality into the 

 upper part of the city. It appeared, too, at a time when Athens was 

 so crowded with those who had fled thither from the adjacent country 

 of Attica for safety from the invading armies of the Peloponnesians and 

 their allies, that many of them were forced to lodge themselves within 

 the turrets of the walls, or wherever they could find a vacant corner. 

 " The city," says the historian, " ws s not able to receive so large a conflux 

 of people :" " afterwards the long walls, and a great part of the Piraeus, 

 were portioned out to them for little dwellings; at the same time, too, 

 the Athenians were fitting out, at the Piraeus, a fleet of one hundred 



* See Note C. 



