George Thurston was a first lieutenant and aide-de-camp on the staff of Colonel Brough, commanding a Federal brigade.  Colonel Brough was only temporarily in command, as senior colonel, the brigadier-general having been severely wounded and granted a leave of absence to recover.  Lieutenant Thurston was, I believe, of Colonel Brough’s regiment, to which, with his chief, he would naturally have been relegated had he lived till our brigade commander’s recovery.  The aide whose place Thurston took had been killed in battle; Thurston’s advent among us was the only change in the personnel of our staff consequent upon the change in commanders.  We did not like him; he was unsocial.  This, however, was more observed by others than by me.  Whether in camp or on the march, in barracks, in tents, or en bivouac, my duties as topographical engineer kept me working like a beaver—­all day in the saddle and half the night at my drawing-table, platting my surveys.  It was hazardous work; the nearer to the enemy’s lines I could penetrate, the more valuable were my field notes and the resulting maps.  It was a business in which the lives of men counted as nothing against the chance of defining a road or sketching a bridge.  Whole squadrons of cavalry escort had sometimes to be sent thundering against a powerful infantry outpost in order that the brief time between the charge and the inevitable retreat might be utilized in sounding a ford or determining the point of intersection of two roads.

In some of the dark corners of England and Wales they have an immemorial custom of “beating the bounds” of the parish.  On a certain day of the year the whole population turns out and travels in procession from one landmark to another on the boundary line.  At the most important points lads are soundly beaten with rods to make them remember the place in after life.  They become authorities.  Our frequent engagements with the Confederate outposts, patrols, and scouting parties had, incidentally, the same educating value; they fixed in my memory a vivid and apparently imperishable picture of the locality—­a picture serving instead of accurate field notes, which, indeed, it was not always convenient to take, with carbines cracking, sabers clashing, and horses plunging all about.  These spirited encounters were observations entered in red.

One morning as I set out at the head of my escort on an expedition of more than the usual hazard Lieutenant Thurston rode up alongside and asked if I had any objection to his accompanying me, the colonel commanding having given him permission.

“None whatever,” I replied rather gruffly; “but in what capacity will you go?  You are not a topographical engineer, and Captain Burling commands my escort.”

“I will go as a spectator,” he said.  Removing his sword-belt and taking the pistols from his holsters he handed them to his servant, who took them back to headquarters.  I realized the brutality of my remark, but not clearly seeing my way to an apology, said nothing.