Other causes are the intemperate amount of intellectual work which is forced on the brain, and the excessive indulgence of the emotions and the passions. Combined with the strenuousness of life is the large element of uncertainty, the intense anxiety, and the restless energy which is the price of success. Added to these may be lack of suitable and sufficient recreation and short hours of restless sleep; the restrictions of a narrow lot, loneliness, and isolation, the frequent repetitions of uninteresting tasks, added to the burdens of maternity, domestic cares, and worries. In cities the ear-strain caused by the incessant noises of the street, the amount of work done by insufficient and improper lighting, the unsanitary mode of life, the improper diet, the monotonous and infertile work, the unhappiness and discontent bred of a life of idleness, or one given to society and gambling, whether bridge, whist or poker, the senseless bolstering of shattered nerves with alcoholic stimulants and beverages, patent medicines, and hypnotics, all add their quota to the breaking down of the nervous system. A man can do a prodigious amount of work if he only varies it with play which really amuses him, or if he substitutes for mental occupation those which involve bodily exercises. In so-called latent gout insomnia is a frequent symptom, or insomnia may develop as the result of bad nervous habits. Insomnia from whatever cause is followed by the impairment of nerve substance and an overloading of the body with toxins. This continued nerve exhaustion leads to oxaluria, uric acid, gout, anemia, gastric and intestinal dyspepsia, muscular insufficiency, and precordial distress. Whatever enfeebles the body by overtaxing the nervous system the waste is in excess of the repair, in all overwork the destructive metamorphosis is greater than the reparative processes, and so there is an accumulation of toxic products and a more or less severe and permanent injury is done the nervous system. Other causes of neurasthenia, not so generally recognized as overwork, are to be found in the pathologic conditions of the intestinal canal, which becomes a veritable culture tube, and absorption from this into the blood constantly takes place. And this condition of putrefaction has to be overcome before relief can be afforded, and in many cases this condition is associated with an insufficiency of the elimination of urine. The large intestine is the seat of an enormous bacteriologic flora; they are not there by millions, but by billions. Some of them are harmless, but not all of them, and if these pathogenic bacteria are present in sufficient quantity, they, too, may produce symptoms of mild poisoning. So, too, may mere indigestion, or the malfunction of any other organ, torpidity of the liver, a deficiency of the excretion of bile, which is generally accompanied by constipation.