FEVERS. 659 



" Though there be no proper variation in the symptoms pe- 

 culiar to the disease, we may come to a very different determi- 

 nation merely from a different state of these collateral circum- 

 stances. If, in the time of a contagion generally prevailing, a 

 person has had a manifest intercourse with those labouring un- 

 der that disease ; if we know nothing of any particular applica- 

 tion of cold inducing it, or at least can only see it concurring 

 with the contagion ; if the season is summer or autumn, if there 

 are no catarrhal symptoms or rheumatic affections ; if there is 

 nothing particular to determine in the habit, young, full or 

 vigorous, and nothing to be expected from haemorrhagic evacu- 

 ations, or artificial venesection ; and, going back to the circum- 

 stances of the disease, if, though the pulse is frequent, to above 

 100, though there are considerable heat, thirst and headach, 

 yet the pulse at the same time not very full, nor very hard, then 

 there can be no doubt that that disease is probably to turn out 

 a typhus or synochus at least, and venesection is improper, or 

 at least we should practise it with much hesitation, and only in 

 the case of a certain ambiguity, from a mixture of these circum- 

 stances ; but though we know that a contagion is prevailing, 

 and that we can trace the disease to it, if the system is remark- 

 ably full and vigorous, and the pulse remarkably hard, still some 

 venesection may be allowed. 



" d. I put a fourth case which differs considerably from all 

 the others in its symptoms. The case occurs in the time of a 

 contagion very generally prevailing, and where that contagion 

 approaches to the worst kind, to a nervous or petechial fever ; 

 where there is a manifest suspicion of an actual contagion 

 caught from the person perhaps living in an hospital, or 

 having a communication with a person labouring under the dis- 

 ease in a. more violent degree ; where the symptoms of the ap- 

 proach of the disease appear in the shape I have formerly des- 

 cribed ; where the attack is gradual and obscure, and even where 

 we can see the disease is formed, yet the symptoms of the in- 

 flammatory appearance are not considerable, and the state of 

 the thirst very moderate. In such cases, there most general- 

 ly occurs a frequent pulse, but which, at the same time, is weak 

 and soft ; there is some headach, not violent, with no suffusion 

 of face, no redness of the eyes ; but there are great complaints of a 



