man Melville gave us some forty years ago. There grows upon the
deserts and the cattle ranges of the Rockies a plant of the leguminosae
family, with a purple blossom, which is called the 'loco'. It is sweet to
the taste; horses and cattle are fond of it, and when they have once
eaten it they prefer it to anything else, and often refuse other food.
But the plant is poisonous, or, rather, to speak exactly, it is a weed of
insanity. Its effect upon the horse seems to be mental quite as much as
physical. He behaves queerly, he is full of whims; one would say he was
"possessed." He takes freaks, he trembles, he will not go in certain
places, he will not pull straight, his mind is evidently affected, he is
mildly insane. In point of fact, he is ruined; that is to say, he is
'locoed'. Further indulgence in the plant results in death, but rarely
does an animal recover from even one eating of the insane weed.

The shepherd on the great sheep ranges leads an absolutely isolated life.
For weeks, sometimes for months together, he does not see a human being.
His only companions are his dogs and the three or four thousand sheep he
is herding. All day long, under the burning sun, he follows the herd over
the rainless prairie, as it nibbles here and there the short grass and
slowly gathers its food. At night he drives the sheep back to the corral,
and lies down alone in his hut. He speaks to no one; he almost forgets
how to speak. Day and night he hears no sound except the melancholy,
monotonous bleat, bleat of the sheep. It becomes intolerable. The animal
stupidity of the herd enters into him. Gradually he loses his mind. They
say that he is locoed. The insane asylums of California contain many
shepherds.

But the word locoed has come to have a wider application than to the poor
shepherds or the horses and cattle that have eaten the loco. Any one who
acts queerly, talks strangely, is visionary without being actually a
lunatic, who is what would be called elsewhere a "crank," is said to be
locoed. It is a term describing a shade of mental obliquity and queerness
something short of irresponsible madness, and something more than
temporarily "rattled" or bewildered for the moment. It is a good word,
and needed to apply to many people who have gone off into strange ways,
and behave as if they had eaten some insane plant--the insane plant being
probably a theory in the mazes of which they have wandered until they are
lost.

Perhaps the lo