This digression on fasting was somewhat necessary, to show how much our diet tends to modify our being. It is well known that troops will display more activity and courage when fasting than after a meal; and an ingenious physician of our day is perfectly correct when he attributes a daring spirit or a pusillanimous feeling to the influence of our stomach. Intellectual weakness, frequently brought on by excesses, has proved a rich source to empiricism; hence the belief in mystic and supernatural agencies, and the power of certain nostrums. Coloured fountain water and bread pills have made the fortune of various quacks, when imaginary cures have relieved imaginary diseases. In our days, numerous have been the recoveries attributed to Hohenloe's prayers. Trusting to mystic numbers, three, five, seven, or nine pills have produced effects, when other numbers less fortunate would have failed. To this hour mankind, even in enlightened nations, are fettered by these absurd trammels. Credulity, and superstition her twin sister, have in all ages been the source whence priestcraft, and quackery have derived their wealth. Next to these rich mines we may rank fashion. The adoption of any particular medicine by princes and nobles will endow it with as great a power as that which was supposed to be vested in regal hands in the cure of scrofula, hence called _king's evil_; and we have too many instances of such cures having been effected by a monarch's touch to doubt the fact. The history of the potato is a strong illustration of the influence of authority: for more than two centuries the use of this invaluable plant was vehemently opposed; at last, Louis XV. wore a bunch of its flowers in the midst of his courtiers, and the consumption of the root became universal in France. The warm bath, so highly valued by the Romans, once fell into disrepute, because the Emperor Augustus had been cured by a cold one, which for a time was invariably resorted to. Thus Horace exclaims, ----Caput ac stomachum supponere fontibus audent Clusinis, Gabiosque petunt et frigida rura. Unfortunately, the means which had relieved Augustus killed his nephew Marcellus; and the _Laconicum_ and the _Tepidarium_ were again crowded with the "fashion."