VOL. LIV,] PHILOSOPHICAL TRANSACTIONS. 105 



is the danger, as the noxious particles, exhaling from the infected person must 

 be more numerous, and consequently have greater force and activity in propor- 

 tion to their distance. 



Some persons are of opinion, that the air must be infected, and that it is the 

 principal cause of these plagues ; whereas he presumes that the ambient air is not 

 otherwise concerned, than as the vehicle, which conveys the venomous particles 

 from one body into another, at least in such plagues, as he had seen at Smyrna 

 and Constantinople; allowing always, that the different constitution of the air 

 contributes very much to propagate the plague; for the hot air dilates and ren- 

 ders more volatile and active the venomous steams, whereas cold air contracts 

 and mortifies them. The person having the plague may be said to have a con- 

 tagious and poisonous air in his room and about him, while at the same time 

 the open air is free from any dangerous exhalations; so that he never was afraid 

 to go into any large house, wherein a plaguy person lived, provided he was con- 

 fined to one room. 



The pestilential fever shows itself first by a chilliness and shiverings, even in 

 the months of July and August, so very like the first approaches of an ague, 

 that it is impossible to distinguish the one from the other at first sight. This 

 cold fit is soon accompanied with a loathing nausea and desire of vomiting, which 

 obliges the patient at last to discharge a vast quantity of bilious matter, with 

 great uneasiness and oppression in the thorax and mouth of the stomach, at- 

 tended sometimes with a dry cough, as in an intermitting fever; and even in 

 this stage it is very difficult to distinguish the one from the other. Next the 

 patient has a violent headach and giddiness, with some slight convulsive motions: 

 he breathes hard; his breath and sweat stink; his eyes are ruddy, he looks 

 frighted, sad, and pale; he has an insatiable thirst; his tongue is yellowish with 

 a red border; he has a total loss of appetite, with restlessness, great inward heat, 

 and more than could be expected from the fever, which is sometimes pretty mo- 

 derate, but grows stronger frequently towards night: the patient very often bleeds 

 at the nose. He continues in that dismal condition for some days, till the ve- 

 nomous matter begins to be separated in some measure from the blood, and dis- 

 charge itself critically on the surface by the cutaneous eruptions of buboes, car- 

 buncles, blains, petechial spots, and some small vesicles or blisters : but all these 

 symptoms are not to be looked for in the same person. When the cutaneous 

 eruptions appear and increase sensibly, the patient finds himself better, and 

 somewhat relieved from the great oppression he laboured under before. Some 

 persons in the above state have a very violent fever, sometimes attended with a 

 delirium and phrenzy; others are stupid, sleepy, and complain of nothing: as 

 one of Captain Hill's men mentioned before; and the young fellow who died of 

 the plague last year. Such as are furious and delirious seldom live so long as 



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