136 HEALTH AND DISEASE 



on muddy roads or hunting in wet districts, and various methods of treat- 

 ment were employed for its cure, and some countries had the credit of 

 possessing soils which contained an unknown but extremely irritating con- 

 stituent. It was, however, always the case that these parts of the country 

 were perfectly harmless in dry seasons, but, having loose loamy soil, were 

 readily converted into mud by heavy rains, and certainly no particular 

 constituent likely to cause irritation was ever discovered, nor with our 

 present knowledge of the subject is there any reason to suspect that such 

 peculiar constituent existed. 



To complete the story it is necessary to relate that some fifty years ago 

 a veterinary surgeon in the midland counties discovered, in the course of 

 his practice, that mud fever never occurred in badly conducted stables, 

 where the attendants were either too lazy or too much occupied to trouble 

 themselves about the mud on the animals' legs and other parts, but turned 

 them into their stalls untouched, and got rid of the mud the following 

 morning with the greatest ease, commonly by the aid of the ordinary birch 

 broom, which, being applied to the parts where the dried mud remained, at 

 once swept it off in the form of fine dust. The discoverer, whose name has 

 escaped the writer's memory, as it has that of all modern writers on the 

 subject, apparently induced some hunting men to try the method, to the 

 great disgust of the grooms, as a matter of course. The system very soon 

 became quite general in large establishments, and cracked heels and erup- 

 tions on the legs arid other parts of the body almost, and in some cases 

 entirely, ceased to appear among the horses. 



In the best establishments, where the proper appliances are always to 

 hand and understood, the practice is to envelop the muddy legs in dry, 

 warm, flannel bandages, and brush the dust out of the coat the following 

 morning. 



As soon as the fact was discovered that washing the muddy skin was 

 injurious, and all the more when hot water was used, a satisfactory physio- 

 logical explanation was at hand; indeed, an experiment by one celebrated 

 physiologist has only to be quoted in order to make the whole matter 

 perfectly clear. 



The experiment was one connected with a series relating to the causes 

 of inflammation under the influence of change of temperature. The ear of 

 a rabbit was subjected to the influence of cold fluid until the blood was 

 driven from the superficial vessels by the contraction of the arteries. The 

 animal was then at once transferred into a warm chamber. The blood im- 

 mediately rushed back into the channels from which it had just before been 

 driven, with the necessary result that some vessels were blocked by the 

 excess of blood, while in others the circulation was going on with rapidity. 



