460 MATER i A MEDIC A AND THERAPEUTICS. 



settling in the tissues and carrying on an indepent metabolism 

 of their own, that is, by living, thriving, and reproducing their 

 like at the expense of the pabulum of the tissues ; that they 

 throw the products of their changes into the venous current, 

 which is thus poisoned and infects the rest of the body ; and 

 that by their life-changes they cause a development of heat 

 which constitutes one part of fever. 



The phenomena of disordered metabolism are necessarily of 

 endless variety and complexity. The most striking symptoms 

 attend that kind of excessive nutrition known as fever, viz., 

 wasting, increased excretion, high temperature, and general 

 functional derangement. To this subject we shall return in 

 chapter xiv. Inflammation may be broadly defined as a similar 

 increase of metabolism in a local form. Defective local nutrition 

 is seen in fatty and calcareous degenerations. In some forms of 

 derangement the results are chiefly appreciable in connection 

 with the tissues themselves, as in obesity ; in others they are 

 discovered in the excretions, e.g. gravel, and glycosuria ; in 

 many instances, such as gout, they can be found both in the 

 tissues and excretions. Occasionally they take the form of ex- 

 cessive and unnatural growth, invading and destroying the 

 normal structures, as in cancer. In other diseases the growth 

 is rapidly followed by decay, as we see in syphilis and tubercle. 

 When. the derangement remains persistently, and establishes 

 itself in the organs, without definite anatomical change, it con- 

 stitutes in part the so-called diatheses gouty, rheumatic, 

 calculoid, etc. Manifestly in this great collection of diseased 

 conditions we have an urgent demand for treatment. 



IV. NATURAL EECOVERY. 



Experience has taught us that many of the most common 

 derangements of metabolism, such as fever, gravel, and rheu- 

 matism, are of but temporary duration, that is, disappear spon- 

 taneously, when the normal conditions have returned or are 

 restored. The forms which natural recovery takes in metabolic 

 disorder are known as reaction and repair, i.e. increased nutritive 

 activity, often associated with inflammation. Unfortunately this 

 class of derangements are peculiarly liable to recur, but this 

 is chiefly because of the return of unhealthy circumstances. 

 Here, too, as elsewhere, recovery is limited by anatomical 

 changes ; but even growth and degeneration will sometimes 

 disappear, under favourable conditions. 



V. THERAPEUTICS. 



The rational treatment of disorders of nutrition is a subject 

 of such large proportions that it can be discussed only in an 



