22 Dr. Henry' sjitrther E.vjm-imenfs on the 



The doctrines in question, however, are not likely to find 

 a more able advocate than Mr. Whewell, whose vigorous and 

 active mind will assuredly afford them every elucidation and 

 development of which they are susceptible. 



IV. Further Experiments on the Dishifectiyig Powers of in- 

 creased Temperatures. By William Henry, M.D.F.R.S. 

 4-c. S-c.* 



IN the Phil. Mag. and Annals, for November, I described a 

 series of experiments, which established the following con- 

 clusions : — 



I. That raw cotton, and various kinds of piece-goods, ma- 

 nufactured for clothing from that or other materials, sustain 

 no injury whatsoever, either of colour or texture, by expo- 

 sure for several hours to a dry temperature of nearly 212° 

 Fahrenheit f . 



II. That the infectious matter of cow-pock is rendered in- 

 ert, by a temperature not below 140° Fahrenheit; from whence 

 it was inferred that more active contagions are probably de- 

 structible, at temperatures not exceeding 212°. This propo- 

 sition it was obviously within the reach of experiment to de- 

 termine. But I had intended to have resigned the inquiry, to 

 those who are engaged in the practice of medicine, as more 

 within their province than my own : when the appearance of 

 malignant cholera at Sunderland determined me immediately 

 to extend the investigation. If that disease be communicable 

 from one j^erson to another, there appeared ground for hope 

 that any new facts or principles, respecting contagion gene- 

 rally, might be brought to bear upon this particular emer- 

 gency. If cholera should be proved not to be so communi- 

 cable, there still would remain many infectious maladies, to 

 which any newly acquired knowledge of the laws of contagion 

 might admit of beneficial application. 



Of diseases generally allowed to be contagious, I could ob- 

 tain access to two only, typhus and scarlatina. The former 

 malady does not, however, answer to all those conditions 

 which are required to render it a fit subject of experiment. 

 It is less distinctly marked, than many other diseases, by cha- 

 racteristic appearances; and it is judged to exist, from a col- 

 lection of symptoms, each of which is occasionally wanting, 

 and each of which, when present, admits of such an infinite 



* Communicated by the Author. 



f The temperature, I luive since found, may in most cases be safely 

 raised forty or fifty degrees higher. 



variety 



