In the army, it is proverbial that the time of fatigue and danger is not the time of disease; it is during the inactive and listless months of a campaign that crowds of patients pass to the hospitals. In both these cases it is the active exercise of the mind giving strength to the brain, and through it, healthy vigour to the body, which produces the effect. Shakspeare has not been unobservant of the consequences of excitement of mind on the bodily functions. In King Henry IV., when Northumberland is told of the fatal tidings from Shrewsbury, and is informed of the death of his son Percy, he breaks out,—
“For this I shall have time enough to mourn.
In poison there is physic; and these news
That would, had I been well, have made me sick,
Being sick, have in some measure made me well:
And as a wretch whose fever-weakened joints,
Like strengthless hinges, buckle under life,
Impatient of his fit, breaks like a fire
Out of his keeper’s arms; even so my limbs,