AND OTHER ORGANS. 43 



version of operations takes place ; the cold chills 

 the surface, stops the perspiration, and directs the 

 current of the blood towards the internal organs, 

 which presently become excited, and, under this 

 excitation, the kidneys, for example, will in a few 

 minutes secrete as much of their peculiar fluid as 

 they did in as many of the preceding hours. The 

 reverse of this, again, is common in diseases ob- 

 structing the secretion from the kidneys ; for the 

 perspiration from the skin is then altered in quan- 

 tity and quality, and acquires much of the peculiar 

 smell of the urinary fluid. 



When the lungs are the weak parts, and their 

 lining membrane is habitually relaxed, accompanied 

 by an unusual amount of mucous secretion from its 

 surface, cold applied to the skin throws the mass 

 of the blood previously circulating there inward 

 upon the lungs, and increases that secretion to a 

 high degree. Were this secretion to accumulate, 

 it would soon fill up the air-cells of the lungs, and 

 cause suffocation; but to obviate this danger, the 

 Creator has so constituted the lungs, that any for- 

 eign body coming in contact with them excites the 

 convulsive effort called coughing, by which a vio- 

 lent and rapid expiration takes place, with a force 

 sufficient to hurry the foreign body along with it, 

 just as peas are discharged by boys with much 

 force through short tubes by a sudden effort of 

 blowing. Thus, a check given to perspiration, by 

 diminishing the quantity of blood previously circu- 

 lating on the surface, naturally leads very often to 

 increased expectoration and cough, or, in other 

 words, to common cold. 



The lungs excrete, as we shall afterward see, a 

 large proportion of waste materials from the sys* 

 tern : and the kidneys, the liver, and the bowels 

 have in so far a similar office. In consequence of 

 this alliance with the skin, these parts are more in- 

 timately connected with each other in healthy and 



