IN HUMAN PHYSIOLOGY. 159 



32. Is a staid, formal promenade suitable exercise? 



No. There is an intimate relation between the brain 

 and the muscles. The mind should be pleasantly em- 

 ployed to obtain the full effect of any exercise. The 

 sports of children are often the very perfection of health- 

 ful gymnastic exercises ? * 



33. Is there any danger in changing the warm clothing of 

 pur daily wear for the thin one of a party ? 



Very great. The body is not as well protected as 

 usual against a sudden change of temperature, as in 

 going from a heated-room to the carriage, and a cold is 

 often the consequence. This may lay the foundation of, 

 or prepare the way for, fatal disease. 



34. Should we retain our overcoat, shawl, or furs, when 

 we come into a warm room ? 



No. The body will become over-heated, the pores be 

 opened, and the skin be rendered susceptible to the 

 change of temperature when we return into the open 

 air. 



35. Which should bathe the oftener, students or out-door 

 laborers ? 



* " The mental operations, like all others, are connected with changes in 

 the material of the body. In all our consciousness the chemical tendencies 

 of the substance of the brain come into play, and thus a chain of action is set 

 up which extends throughout the system. The influence of these brain- 

 changes is felt wherever a nerve travels, and modifies, invigorates, or de- 

 praves the action of every part. Experience gives ample proof of this fact to 

 every one, as in the sudden loss of appetite a piece of bad news will cause, or 

 in the watering of the mouth excited by the thought of food. And the history 

 of disease abounds in evidence of a similar kind : hair becoming gray in a 

 single night from sorrow, milk poisoning an infant from an attack of passion 

 in the nurse, permanent discoloration of the skin from terror, are among the 

 instances on record." HINTON. 



