It might have been the fading light of the waning day that cast the peculiarly sombre shadow on the Captain's house as we drew up to it; but I thought the same shadow must have fallen on the Captain's face, when he appeared in the door to greet us. Presently Mrs. Arnold fluttered up in white muslin and blue ribbons; and both did their best to make us comfortable. How my husband felt, I don't know; but they did not succeed in making me feel comfortable. Perhaps the absence of the bright fire made the rooms look so dark, even after the lights had been brought in – there was certainly a change. Supper was placed on the table, but I missed Constantia's round face in the dining-room. In answer to my question regarding her, I was told she had expressed so strong a desire to return to the States that she had been sent to Fort – , there to await an opportunity to go in. Lieutenant Rockdale's absence I noticed also. He did not mess with them any more, I was informed.

My attention was attracted to a conversation between Captain Arnold and my husband. The guard-house, he told him, was at present occupied by two individuals who had made their appearance at Fort Desolation several days ago, and had tried to prevail on the Captain to sell them some of the government horses, and arms and ammunition, offering liberal payment, and promising secrecy. They were Americans; but as the number of American settlers, or white settlers, in this country is so small, it was easy for the Captain to determine that these were not of them, and their dress and general appearance led him to suspect that they belonged to that despicable class of white men who make common cause with the Indian, in order to rob and plunder, and, if need be, murder, those of their own race. Of course they had not made these proposals directly and openly to the Captain – at first representing themselves as members of a party of miners going to Pinos Altos; but they soon betrayed a familiarity with the country which only years of roaming through it could have given them. He had felt it his duty to arrest them at once, but had handcuffed them only to-day, and meant to send them, under strong escort, to Fort – , where their regimental commander was stationed, as soon as some of the men from the picket-posts could be called in.

It was late when we arose from the supper-table, and the Captain and my husband left us, to go down to the guard-house, while Mrs. Arnold led me into the room where their bed stood. This room had but one window – of which window the Captain was very proud. It was a French window, opening down to the ground. Throwing it open, Mrs. Arnold said:

"What a beautiful moon we have to-night; let us put out the candle and enjoy the moonshine" – with which she laughingly extinguished the light, and drew my chair to the window.

From where I sat I could just see the men's quarters and the guard-house, though it might have been difficult from there to see the window. We had not been seated long when I fancied I heard a noise, as though of some one stealthily approaching from somewhere in the direction to which my back was turned; then some one seemed to brush or scrape against the outside wall of the house, behind me. "What's that?" I asked in quick alarm. It had not remained a secret to Mrs. Arnold that I was an unmitigated coward; so she arose, and saying, "How timid you are! – it is the dog; but I will go and look," she stepped from the low window to the ground outside, and vanished around the corner of the house. Some time passed before she returned, and with a little shudder, sprang to light the candle.

"How chilly it is getting," she exclaimed; and then continued, "it was the dog we heard out there. Poor fellow; perhaps the cook had forgotten him, so I gave him his supper."

Rising from my seat to close the window on her remark about the cold, I stepped to the opposite side from where I had been sitting; and there, crossing the planks that lay over the slimy creek, and going towards the commissary buildings, was a man whose figure seemed familiar: I could not be mistaken – it was Lieutenant Rockdale. No doubt the man had a right to walk in any place he might choose; but, somehow, I could not help bringing him in connection with "the dog, poor fellow," for whom Mrs. Arnold had all at once felt such concern.

Soon the gentlemen returned, and we repaired to the parlor, where a game of chess quickly made them inaccessible to our conversation. The game was interrupted by a rap at the front door, and Harry, the sergeant whom Mrs. Arnold had compelled to mount her black horse that day, appeared on the threshold. In his face there was a change, too; his eyes flashed with an unsteady light as he opened the door, and ever and again, while addressing the Captain – whose thoughts were still half with the game – his looks wandered over to where Mrs. Arnold sat. We were so seated that the Captain's back was partly toward her when he turned to the sergeant; and he could not see the quick gesture of impatience, or interrogation, that Mrs. Arnold made as she caught the mulatto's eye. Involuntarily, I glanced toward him – and saw the nod of assent, or intelligence he gave in return.

The sergeant had come to report that the prisoners in the guard-house had suddenly asked to see the Captain: they had disclosures to make to him. When Captain Arnold returned, his face was flushed.

"The villains!" he burst out. "They had managed to hide about five thousand dollars in United States bank-notes about them, when they were searched for concealed weapons, and they just now offered it to me, if I would let them escape. Not only that, but from something one of them said, I have gained the certainty that they are implicated in the massacre of the party of civilians that passed through here about two months ago: you remember, the General ordered out a part of K company, to rescue the one man who was supposed to have been taken prisoner. The wretches! But I'll go myself, in the morning, to relieve the men from picket-duty, and select the best from among them to take the scoundrels to Santa Fé!"

When about to begin my toilet the next morning, I gave a start of surprise. Was that what had made the house look so dark and changed? Before me stood a large tin wash-basin – of the kind that all common mortals used out here – and the beautiful toilet-set of china, with its splendors of gilt-edge and moss-roses, had all disappeared – all save the soap-dish and hot-water pitcher, which were both defective, and looked as though they had gone through a hard struggle for existence.

When our ambulance made the ascent of the little steep hill that hides Fort Desolation from view, I saw three horses led from the stable to the Captain's house – the Captain's horse and two others. He was as good as his word, and before another day had passed, the two men penned up in that tent there would be well on their way to meet justice and retribution. A solitary guard, with ebony face and bayonet flashing in the morning sun, was pacing back and forth by the tent; and walking briskly from the commissary buildings toward the men's quarters, was Harry, the mulatto sergeant.

From the first glance I had at Mrs. Kline's face, when we reached Fort – , I knew that the mystery of the change at Fort Desolation would be solved here. Constantia was there, and acting as cook in Dr. Kline's family. She was an excellent cook, and we did ample justice to her skill at suppertime. The gentlemen leaving the table to smoke their cigars, Mrs. Kline and I settled down to another cup of tea and médisance. From what Constantia had stated on coming to Fort – , it would seem that in some way Captain Arnold's suspicions had been aroused in regard to the friendship of Lieutenant Rockdale for his wife. About two months ago, he one day pretended to start off on a tour of inspection to the picket-posts; but returned, late the same night, by a different road. Stealing into the house through the kitchen, he had, rather unceremoniously, entered the bed-room, where he found Lieutenant Rockdale toasting his bare feet before the fire. Raising his carbine to shoot the man, Mrs. Arnold had sprung forward, seized his arms and torn the gun from him. In the confusion that followed, the toilet-set referred to, and other articles of furniture, were demolished: but Constantia, who had crept in after the Captain, to prevent mischief, if possible, gave it as her opinion that Mrs. Arnold "had grit enough for ten such men as him an' de leftenant."

"If you did but know the ingratitude of the creature," continued Mrs. Kline, "and the devotion her husband has always shown her!" And she gave me a brief sketch of her career: Married to Arnold just at the breaking out of the war, and of poor parents, she had driven him almost to distraction by her treatment, when thrown out of employment some time after. At last he went into the Union forces as substitute – giving every cent of the few hundred dollars he received to his wife, who spent it on herself for finery. Later, when for bravery and good conduct he was made lieutenant in a negro regiment, she joined her husband, and finally came to the Territory with him. In their regiment, it was well known that he had always blindly worshipped his wife; and that she had always ruled him, his purse, and his company, with absolute power.

Before retiring for the night, we debated the question: Should we remain the next day at Fort – , or proceed on our journey? The mules needed rest, as well as the horses, for the quartermaster could not furnish fresh mules, which we had rather expected; still, my husband was anxious to reach Santa Fé as soon as possible – and we left the question of our departure where it was, to settle it the next morning at breakfast. The news that came to Fort – , before the next morning, made us forget our journey – for that day, at least. Captain Arnold had been murdered! The big, true-hearted man was lying at Fort Desolation – dead – with his broken eyes staring up to the heaven that had not had pity on him – his broad breast pierced with the bullet that a woman's treachery had sped!

Before daybreak, a detachment of six men had come in from Fort Desolation to Fort – , to report to the commander of their regiment that Captain Arnold had been assassinated, and Sergeant Henry Tulliver had deserted, taking with him one horse, two revolvers, and a carbine. Captain Arnold had started out the morning before, with only two men, to call in the picket-posts. An hour later, the two men had come dashing back to the fort, stating that they had been attacked, and Captain Arnold killed, by the two white men who had been confined in the guard-house. It was ascertained then, for the first time, that the prisoners had made their escape. A detachment of men was sent out with a wagon, and the Captain's body brought in – the men, with their black faces and simple hearts, gathered around it, with tears and lamentations, heaping curses on the villains who had slain their kind commander.

Suddenly a rumor had been spread among them that Harry, the sergeant, had set the prisoners free; and instantly, a hundred hoarse voices were shouting the mulatto's name – a hundred hands ready to take the traitor's life. Vainly Lieutenant Rockdale – who, after the Captain's departure, had at once repaired to his house – tried to check the confusion, that was quickly ripening into mutiny: the excitement only increased, and soon a crowd of black soldiers moved toward the men's quarters, with anything but peaceful intentions. Perhaps Harry's conscience had warned him of what would come, for while the mob were searching the quarters, a lithe figure sprang over the planks across the creek, ran to the stables below the Captain's house, and the next moment dashed over the road, mounted on a wild-looking, black horse.

Could they but have reached him – the infuriated men, who sent yells and carbine-balls after the fugitive – he would have been sacrificed by them to the manes of the murdered man; and perhaps this effect had been calculated on, when the fact of his having liberated the prisoners had been brought, to their ears.

"How did it come to their ears?" I asked of the Doctor, under whose care one of the six men, overcome with fatigue and excitement, had been placed. It seems that Mrs. Arnold had expressed her conviction of the sergeant having liberated the prisoners to Lieutenant Rockdale in little Fred's hearing, and the boy had innocently repeated the tale to the men.

In the afternoon of the same day, the detail had been made of the men who brought the news to Fort – ; but when the detachment had been only an hour or two on the way, they found the trail of the escaped prisoners. The men could not withstand the temptation to make an effort, at least, to recapture them. They knew them to be mounted, for the two horses which Sergeant Tulliver had that morning separated from the herd were missing; but the trail they followed showed the tracks of three horses, which led them to suppose that Harry had found the men and joined them.

But the trail led farther and farther from the road, and fearing to be ambushed, they turned back, leaving the man who had been driven from the companionship of his brethren by a woman's treachery, to become one of the vultures that prey on their own kind.