Introduction to the Study of Disease 



IN order to have a correct understanding of the 

 elements of disease, it is expedient for the 

 amateur to make himself acquainted with the 

 conditions of health, which can only be done 

 by cultivating the power of observation, together 

 with a just appreciation of the various habits and 

 laws governing the functional powers of the vari- 

 ous organs, the regulation of which forms the 

 fundamental principles not only in health, but in 

 any departure from the same, i.e., disease. The 

 study of the healthy functions of the body is 

 embraced within the title of physiology, and that 

 of disease, under the term pathology, whilst the 

 symptoms and signs presented to the mind of the 

 observer are known as the so-called clinical 

 features, though such features are not necessarily 

 indicative of any particular disease, but when they 

 are, are spoken of as pathognomonic ; thus, for 

 instance, an excessive secretion of urine is positive 

 evidence of the existence of diabetes, and the 

 passage of red urine, in cattle and sheep, has 

 the same significance, though indicative of another 

 malady, i.e. red water. The same remark is 

 equally applicable to ulceration of the nasal mem- 

 brane in Glanders, and numerous other instances 

 might be given. The causation of disease is 



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