The best thing to do in such a case is to adopt some abstract theory
of action without delay, and put it into practice without
hesitation. Then if you fail, you can throw the responsibility on
the theory.

Now, in regard to flies there are two theories. The old,
conservative theory is, that on a bright day you should use a dark,
dull fly, because it is less conspicuous. So I followed that theory
first and put on a Great Dun and a Dark Montreal. I cast them
delicately over the fish, but he would not look at them.

Then I perverted myself to the new, radical theory which says that
on a bright day you must use a light, gay fly, because it is more in
harmony with the sky, and therefore less noticeable. Accordingly I
put on a Professor and a Parmacheene Belle; but this combination of
learning and beauty had no attraction for the ouananiche.

Then I fell back on a theory of my own, to the effect that the
ouananiche have an aversion to red, and prefer yellow and brown. So
I tried various combinations of flies in which these colours
predominated.

Then I abandoned all theories and went straight through my book,
trying something from every page, and winding up with that lure
which the guides consider infallible,--"a Jock o' Scott that cost
fifty cents at Quebec." But it was all in vain. I was ready to
despair.

At this psychological moment I heard behind me a voice of hope,--the
song of a grasshopper: not one of those fat-legged, green-winged