24 Dr. Henry's/urther Experiments on the 



even by a person situated williin its sphere, depends so much 

 on predisposition, and on otiier circumstances, that a much 

 laro'er induction of facts would be necessary, to establish the 

 absence offotnitcs in any case Uke the foregoing. I do not, 

 therefore, lay much stress on so limited a number of facts. 

 It may be proper, however, to mention, that, during the first 

 trial, the person subjected to it was much fatigued by previous 

 exercise ; and that at the close of it he had observed an un- 

 broken fast of eight hours, — a state of the animal system ex- 

 tremelv favourable to the efficacy of contagion, if any had 

 been present. 



In Scarlatina, however (including both scm-l. simplex, and 

 scarl. anginosa), we have a disease admirably adapted for fur- 

 nishing the necessary evidence. No one doubts of its being infec- 

 tious. Perhaps, indeed, of all the diseases with which nosologists 

 have arranged it (the exanthemata), it gives birth to the most 

 active and durable contagion. The interval, between expo- 

 sure to infection and the commencement of the disease, is un- 

 usually short, and may be stated at from two or three, to six 

 days. When the infection has been received, the malady, pro- 

 duced by it, begins to be contagious before the scarlet efflo- 

 rescence appears ; and it continues so even after the subsequent 

 desquamation of the cuticle. Every medical practitioner of 

 much experience must have been baffled in his attempts to 

 dislodore it from families, in which it had gained a footing. 

 In such cases, its revival at distant intervals of time has been 

 sometimes traced to clothes or bedding, which had been care- 

 lessly laid by, without being sufficiently purified. In the state 

 oifomites, this species of infection has lain dormant for many 

 months. Dr. Hildenbrand, for example, relates that he car- 

 ried the infection in a coat, which had not been worn since 

 his attendance on a scarlatina patient a year and a half before, 

 from Vienna into Podolia, where the disease had till then been 

 almost unknown*. Generally speaking, too, scarlatina is a 

 distinct and well characterized disease; and whenever it is 

 otherwise, the doubts may commonly be removed, by com- 

 paring it with the prevailing epidemic. 



These considerations rendered me extremely desirous to 

 try the disinfecting powers of elevated temperatures over the 

 contagion of scarlatina. It fortunately happened that in one 

 of the wards of the House of Recovery, a patient (a female, 

 ao-ed nineteen, of the name of Gerrard) was suffering under 

 that form of the disease, which has been termed scarlatina 



* Did. de Med, xix. p. l.ifi. 



anginosa. 



