valley of the Rondout must lie.  The vast stretch of woods, when it came into view from under the foot of Slide, seemed from our point of view very uniform.  It swept away to the southeast, rising gently toward the ridge that separates Lone Mountain from Peak-o’-Moose, and presented a comparatively easy problem.  As a clew to the course, the line where the dark belt or saddle-cloth of spruce, which covered the top of the ridge they were to skirt, ended, and the deciduous woods began, a sharp, well-defined line was pointed out as the course to be followed.  It led straight to the top of the broad level-backed ridge which connected two higher peaks, and immediately behind which lay the headwaters of the Rondout.  Having studied the map thoroughly, and possessed themselves of the points, they rolled up their blankets about nine o’clock, and were off, my friend and I purposing to spend yet another day and night on Slide.  As our friends plunged down into that fearful abyss, we shouted to them the old classic caution, “Be bold, be bold, be not too bold.”  It required courage to make such a leap into the unknown, as I knew those young men were making, and it required prudence.  A faint heart or a bewildered head, and serious consequences might have resulted.  The theory of a thing is so much easier than the practice!  The theory is in the air, the practice is in the woods; the eye, the thought, travel easily where the foot halts and stumbles.  However, our friends made the theory and the fact coincide; they kept the dividing line between the spruce and the birches, and passed over the ridge into the valley safely; but they were torn and bruised and wet by the showers, and made the last few miles of their journey on will and pluck alone, their last pound of positive strength having been exhausted in making the descent through the chaos of rocks and logs into the head of the valley.  In such emergencies one overdraws his account; he travels on the credit of the strength he expects to gain when he gets his dinner and some sleep.  Unless one has made such a trip himself (and I have several times in my life), he can form but a faint idea what it is like,—­what a trial it is to the body, and what a trial it is to the mind.  You are fighting a battle with an enemy in ambush.  How those miles and leagues which your feet must compass lie hidden there in that wilderness; how they seem to multiply themselves; how they are fortified with logs, and rocks, and fallen trees; how they take refuge in deep gullies, and skulk behind unexpected eminences!  Your body not only feels the fatigue of the battle, your mind feels the strain of the undertaking; you may miss your mark; the mountains may outmanoeuvre you.  All that day, whenever I looked upon that treacherous wilderness, I thought with misgivings of those two friends groping their way there, and would have given much to know how it fared with them.  Their concern was probably less than my own, because they were more ignorant of what was before them.  Then there was just a slight shadow of a fear in my mind that I might have been in error about some points of the geography I had pointed out to them.  But all was well, and the victory was won according to the campaign which I had planned.  When we saluted our friends upon their own doorstep a week afterward, the wounds were nearly healed and the rents all mended.