It is no rare thing for the "escolta" itself to be suspected; or at least the officer commanding it. More than once has the connivance been established, by evidence, in a court of law! Still rarer does punishment follow in any proportion to the diabolical crime--the criminal usually getting clear by turning _salteador_ himself! On the other hand, there are times when an honest officer--one of action and courage--makes his appearance upon the scene; and by the energetic performance of his duty becomes a terror to the bandits--rendering the roads comparatively safe. Unluckily this improved state of things continues but for a short period. Some new _grito_--followed by the usual spasmodic revolution-- brings about a change, both in rulers and robbers; who sometimes also _exchange_ situations! The energetic officer is snatched away from the scene--either by death, or promotion to a better post; and the passage of the roads becomes perilous as ever. Such were a few of the revelations I had from the lips of Don Samuel Bruno, as we journeyed along the lone causeway leading by the lake Tezcoco. There were two things still unexplained, and which no little puzzled me: how my guide had contrived to come safe out of so many hair-breadth perils? And how he managed to keep his peace with the _salteadores_? The explanation was asked for, and freely given. The secret lay in a nutshell. _No matter what happened, Sam always remained neutral_! "Ye see, cap'n," said he--by way of explanation rather than apology, "as I'm only the driver, they hain't no ill-will agin me. They know I'm but doin' my duty. Besides, if thar was no driver, there ked be no _diligencia_; an' if _it_ war off the road, all the wuss for them, I reck'n. They look upon me as bein' nootral; otherwise I needn't go that way agin. I keep on my box, an' leave 'em do as they've a mind--knowin' that I ked be of no sarvice to the poor passengers that's bein' plundered. I kin do _them_ more good, arter it's all over--by drivin' them on to thar destinashun." For a time my companion was silent, and I too. I became absorbed in thoughts, cheerless, if not absolutely sad. The sight of Tezcoco, along whose shores we were now proceeding, was not calculated to cheer me. The lake looked still, and dark as Acheron itself--its sombre silence relieved only at intervals by sounds yet more lugubrious--the scream of the great curlew, or the screech-like call of the American ibis! Giving way to a string of unpleasant fancies, I rode on without speaking to any of my comrades. I was roused from my reverie by the voice of Sam Brown; who appeared desirous of once more entering into conversation. "Cap'n!" said he, spurring alongside of me, and dragging the pack-mule after him. "'Scuse me for intrudin' upon you; but I've got somethin' more to say about this business we're on. What air ye goin' to do?"