habit.

I close this brief reference to the remoter consequences of the habits
of the opium-eater by calling the attention of the reader to the
physical weakness with consequent inaptitude for continuous exertion
which forms a part of my own experience. Unable as I am to refer it to
any _immediate_ cause, frequent and sudden prostration of
strength occurs, accompanied by slight dizziness, impaired sight, and
a sense of overwhelming weakness, though never going to the extent of
absolute faintness. Its recurrence seems to be governed by no rule. It
sometimes comes with great frequency, and sometimes weeks will elapse
without a return. Neither the state of the weather, nor any particular
condition of the body, appears to call it out. It sometimes is
relieved by a glass of water, by the entrance of a stranger, by the
very slightest excitement, and it sometimes resists the strongest
stimulants and every other attempt to combat it. I can record nothing
else respecting this visitant except that its presence is always
accompanied with a singular sensation in the stomach, and that the
entire nervous system is affected by its attack.

The inaptitude for steady exertion is not merely the consequence of
this occasional feeling of exhaustion, but is for a time the
inevitable result of the accumulated pain and weakness to which his
system, not yet restored to health, is still subject. This impatience
of continued application to work, which is common to all opium-eaters,
and which does not cease with the abandonment of the habit, seems to
result in the first case from some specific relation between the drug
and the meditative faculties, promoting a state of habitual reverie
and day-dreaming, utterly indisposing the opium-user for any
occupation which will disturb the calm current of his thoughts, and in