(578 ACUTE INFECTIOUS DISEASES. 



of water by evaporation and sweating ; it does not occur it the patients 

 replace the loss of water by drinking freely. During the sweating 

 stage, the bodily temperature gradually falls, and toward its end be- 

 comes nearly normal. When the paroxysm is over, and the apyrexia 

 begins, most patients fall into a deep sleep, from which they awake 

 much fatigued and dull, it is true, but feeling relatively well. Wher 

 all the stages of the paroxysm are well marked, the disease is called 

 an intermittens completa ; if one or other stage fails or is indistinct, it 

 is called incompleta. In rare cases, the stages of the fever are said 

 not to follow the regular order ; for instance, the cold stage closes the 

 paroxysm instead of opening it (typus in versus). 



After the first paroxysms of intermittent, the apyrexia is rarely 

 " pure." *' The patients have no fever, it is true ; in some cases the 

 temperature is even low and the pulse slow; but the appetite is 

 often poor ; the tongue coated, digestion disturbed ; the patients are 

 sensitive to changes of temperature, and complain of an indefinite feel- 

 ing of illness. After a few paroxysms the disturbances usually sub- 

 side, and during the apyrexia the only symptoms we notice are 

 steadily-increasing debility and more evident impoverishment of the 

 blood. If intermittent fever is very protracted, the apyrexias often 

 become impure again, and the intermittent type approaches the remit- 

 tent (febris intermittens subcontinua). 



According to the rhythm in which the paroxysms follow each other, 

 we distinguish intermittens quotidiana, tertiana, and quartana. In the 

 quotidian, the paroxysms recur in nearly or exactly twenty-four hours ; 

 in the tertian, in twice twenty-four hours ; in the quartan, in three 

 times twenty-four hours after the commencement of the last one. It 

 is less certain if there be also a five, six, or seven day rhythm, or if 

 the intervals be even longer. The most frequent varieties are the 

 tertian and quotidian. If the paroxysms recur at an earlier hour than 

 it did the last fever-day, the disease is called anticipating, in the oppo- 

 site case it is called retarding. By continued anticipation or retarda- 

 tion, the rhythm of the fever may change, and a tertian may become a 

 quotidian, or the reverse. If a paroxysm last almost till the com- 

 mencement of the next one, we have a febris intermittens subintrans. 

 When the apyrexia of a quotidian, tertian, or quartan intermittent is 

 interrupted by a weak, short paroxysm, which often occurs at a differ- 

 ent time of day, it is called febris intermittens duplicata. In quo 

 tidiana duplicata there are two attacks each day, one severe, the 

 other mild ; in tertiana duplicata there is one attack each day, but 

 one day it is mild, the next weak, etc. ; in quartan duplicata, parox- 

 ysms occur on two successive days, while the third day remains free. 

 Intermittent fever never begins double ; this rhythm usuallv develops 



