For a few days Lord James was able to bring Genevieve encouraging reports of a vast improvement in Blake's spirits. But still the engineer-inventor failed to make the headway he had expected toward the solution of the complex and intricate problem of the dam. In consequence, he re-doubled his efforts and worked overtime, permitting himself less than four hours of sleep a night. His meals he either went without or took at his desk.

All the urgings of Griffith and Lord James could not induce him to cease driving himself to the very limit of endurance. Day by day he fell off, growing steadily thinner and more haggard and more feverish; yet still he toiled on, figuring and planning, planning and figuring.

But on the morning of the day set for Genevieve's ball, the weary, haggard worker tossed his pencil into the air, and uttered a shout that brought his two friends on a run from Griffith's office.

"I've got it! I've got it!" he flung at them, as they rushed in. He thrust a tablet across the table. "There's the proof. Check those totals, Grif."

Lord James leaned over the table to grasp Blake's hand.

"Gad, old man!" he said. "Just in time for you to go to the ball."

Griffith paused in his swift checking of Blake's final computations.
"Ball? Not on your sweet life! He's going to bed."

"You promised to go, Tom," said Lord James.

"Did I?" replied Blake. "Well, then, of course I'm going."

"Of course!" jeered Griffith. "It's no use arguing against a mule.
Can't help but wish you hadn't reminded him, Mr. Scarbridge."

"The change will do him good," argued Lord James.

"I'm in for it, anyway," said Blake. "Only thing, I wish I could get some sleep, in between. Well, here's for a good hot bath and a square meal. That'll set me up."

Griffith shook his head. "I'm not so sure. What you need is twelve hours on your back."

That he was right the Englishman had to admit himself with no little contrition before the ball was half over.

Blake presented a good figure, and though he talked little and danced less, yet on the whole he produced a very good impression. As Lord James had once observed, with regard to his visit at Ruthby Castle, Blake's bigness of mind seemed to be instinctively sensed by nearly all those with whom he came in contact on favorable terms.

But, from the first, he avoided Genevieve with a persistence so marked as almost to disarm Mrs. Gantry.

Most of his few dances were with Dolores, who discovered that, notwithstanding his evident weariness, he was astonishingly light on his feet and by no means a poor waltzer. But after midnight she found it increasingly difficult to lure him out on the floor whenever she was seized with the whim to favor him by scratching the name—and feelings—of some other partner.

More than once Lord James urged him to go home and turn in. Blake's reply was that he knew he ought not to have come to the ball, but since he had come, he proposed to stick it out,—he would not be a quitter. So he stayed on, hour after hour, weary-eyed and taciturn, but by no means ill-humored. Many of the wall-flowers and elderly guests poured their chatter into his unhearing ear, and thought him a most sympathetic listener.

Genevieve, however, with each glimpse that she caught of him, perceived how his fatigue was constantly verging toward exhaustion. At last, between three and four in the morning, she cut short a dance with young Ashton and asked Lord James to take her into the library for a few minutes' rest. He was with Dolores, but immediately relinquished her to Ashton, and went off with Genevieve.

They soon passed out of the chatter and whirl of the crowd into the seclusion of the library. Genevieve led the way to her father's favorite table, but avoided the big high-backed armchair. Lord James placed a smaller chair for her at the other side of the table, facing the door of the cardroom, and as she sank into it he took the chair at the corner.

"Ah!" sighed Genevieve. "It's so restful to get away from them all for a few moments."

"I wonder you're not still more fatigued. Awful crush," replied Lord James. "I daresay you haven't had any chance all evening for a nibble of anything. Directed that something be brought to us here."

"That was very thoughtful of you. I do need something. I'm depressed—It's about Tom. I brought you in here to ask your opinion. He has looked so haggard and worn to-night."

"Overwork," explained Lord James. "He's been hard at it, day and night, in that stuffy office. He could stand any amount of work out in the open. But this being cooped up indoors and grinding all the time at those bally figures!"

"If only it's nothing worse! I'm so afraid!"

"No. It hasn't come on again; though that may happen any time when he's so nearly pegged. Must confess, I blame myself for urging him to come to-night. But he said he had solved the big problem, and I thought the change would do him good—relax his mind, you know. Egregious mistake, I fear. I've urged him to go; but he insists upon sticking it out."

"But you're certain that he—has—done nothing as yet?"

"No, indeed, I assure you! This over-fatigue—I'm not even certain whether the craving is on him or not…. You'll pardon me, Miss Genevieve—but do you realize how hard you have made it for him, cutting him off from all help in his desperate struggle?"

"Then he is fighting all alone?" she exclaimed.

"Yes. He won't allow even me to jolly him up now. He's given me the cold shoulder. Said the inference to be drawn from your conditions was that he should have no help whatever."

"Isn't that brave!—isn't that just like him!" cried the girl, her eyes sparkling and cheeks aglow. "He will win! I feel sure he'll win!"

Lord James looked down at the table, and asked in rather an odd and hesitating tone: "We must hope it. But—if he does win—what then?"

Blake came slowly into the room through the doorway behind them, his head downbent as if he were pondering a problem.

Unaware of the newcomer, Genevieve looked regretfully into the troubled face of her companion, and answered him with absolute candor. "Dear friend, need I repeat? I am very fond of you, and I esteem you very highly. Yet if he succeeds, I must say 'no' to you."

As the young Englishman bent over, without replying, Blake roused from his abstraction and perceived that he was not alone in the room.

"Hello—'scuse me!" he mumbled. Half startled, they turned to look at him. He met them with a rare smile. "So it's you, Jeems—and Miss Jenny. Didn't mean to cut in on your 'tates-an'-tay, as the Irishman put it."

He started to turn back. Genevieve sought to stop him. "Won't you join us, Tom?"

"Thanks, no. It's Jimmy's sit-out. I just stepped in here to see if I could find a book on the differential calculus. Been figuring a problem in my head all evening, and there's a formula I need to get my final solution. I know that formula well as I know you, but somehow my memory seems to've stopped working."

"Those bally figures! Can't you ever chop off?" remonstrated Lord James. "You're pegged. Come and join us. Miss Genevieve will be interested to hear about the dam."

"I'm interested, indeed I am, Tom. Papa says you are working out a piece of wonderful engineering."

Blake stared. "What does he know about it?"

"I suppose his consulting engineer told him—your friend Mr. Griffith."

"Grif's not working for him now."

"Indeed? Then I misunderstood. Anyway, you must come and explain all about the dam."

"Well, if you insist," said Blake. He went around to the big armchair, across from Genevieve, and sat down wearily while explaining: "But the dam is a long way from being built. It's all on paper yet, and I've had to rely on the reports sent in by the field engineers."

A footman came in and set food and wine before Genevieve and Lord James. Blake went on, with quick-mounting enthusiasm, heedless of the coming and going of the soft-footed, unobtrusive servant.

"That's the only thing I'm afraid of. Would have liked to've gone over the ground myself first. But they had two surveys, and the field notes check fairly well. Barring mistakes in them, I've got the proposition worked out to a T. It's all done except some figuring of details that any good engineer could do. Just as well, for I'm about all in. Stiffest proposition I ever went up against."

He sank back into the depths of the big chair, with a sudden giving way of enthusiasm to fatigue. Lord James reached out his plate to him.

"You are pegged, old man," he said. "Have a sandwich."

"No," replied Blake. "I'm too played out to eat. Just want to rest."

Genevieve had been scrutinizing his face, and her deepening concern lent a note of sharpness to her reproach: "You're exhausted! You should not have come to-night!"

"Couldn't pass up a dance at your house, could I?" he smilingly rejoined. "Don't you worry about me. It's all right, long's I've got that whole damn irrigation system worked out."

"Ha! ha! old man!" chuckled Lord James. "That expresses it to a T, as you put it. But wouldn't it be better form to say, 'the whole irrigation dam system'?"

Blake smiled shamefacedly. "Did I make a break like—such as that?
'Scuse me, Miss Jenny. I'm sort of—I'm rather muddled to-night."

"No wonder, after all you've done," said Genevieve. She added, with a radiant smile, "But isn't it glorious that you've finished such a great work! Papa says that you've actually invented a new kind of dam."

The silent footman had reappeared with another plate and glass of wine. He glided around behind Blake, who had leaned forward again with the right arm upon the edge of the table. Unconscious of the servant, who placed the plate and wine glass near him on his left and quietly glided from the room, the engineer responded to Genevieve's remark with an animation that might have been likened to the last flare of a dying candle.

"No," he said, "it's not exactly a new kind of dam—not an invention. I did work out once a modification of bridge trusses which some might call an invention,—new principle in the application of trusses to bridge structure. Allows for a longer suspension span on cantilever bridges."

"But this Zariba Dam," remarked Lord James; "I've yet to learn, myself, just how you worked it out."

"Well, it wasn't any invention; just a sort of discovery how to combine a lot of well-known principles of construction to fit the particular case. You see, it's this way. There was only one available site for the dam, and the mid-section of that was bottomless bog; yet provision had to be made for a sixty-five foot head of water."

"You take him, Miss Genevieve," said Lord James. "They have no solid ground to build on, and the water above the dam is to be sixty-five feet deep."

"I should think the dam would sink into the bog," remarked Genevieve.

"That was one factor in the problem," said Blake. "Solved it by putting the steel reinforcement of the concrete in the form of my bridge-truss span. The whole central section could hang in midair and not buckle or drop. That was simple enough, long's I had my truss already invented. The main difficulty was that deep bog. If you studied hydrostatics, you'd soon learn that a sixty-five foot head of water puts an enormous pressure on the bed of a reservoir."

Absorbed in his explanation, Blake unconsciously grasped the wine glass in his left hand, as he went on:

"That pressure would be enough to make the water boil down through the bog and clear out under the deepest foundation any of the other engineers had been able to figure out. Well, I figured and figured, but somehow I couldn't make anything in the books go. At last, when I had almost given up—"

"No! you couldn't do that," put in Lord James.

Blake smiled at him, and paused to grasp again his broken thread of thought. In the fatal moment when his wakeful consciousness was diverted, and before Lord James could interpose to avert the act, his subconsciousness automatically caused his left hand to raise the glass which it held to his lips.

Before he was aware of what he was doing, he had taken a sip of the wine. An instant afterward the glass shattered on the floor beside his chair, and he clutched at the edge of the table, his face convulsed and his eyes glaring with the horror of what he had done.

"Hell!" he gasped.

Genevieve rose and started back from the table, shocked and frightened by what she mistook for an outburst of rage or madness. Lord James rose almost as quickly, no less shocked and quite as uncertain as to what his friend would do.

[Illustration: His jaw closed fast,—and in the same instant his outstretched hand smashed down upon the wine glass]

"Tom!" he called warningly, and he laid his hand on Blake's shoulder.

Almost beside himself in the paroxysm of fear and craving that had stricken his face white and half choked him with seeming rage, Blake shook off the restraining hand, and gasped hoarsely at Genevieve: "Wine!—here—in your house! God! Shoved into my hand! Smell wasn't enough—must taste it! God! Tough deal!"

"Lord Avondale!" cried Genevieve, and she turned to leave the room, furiously indignant.

"Gad! old man!" murmured Lord James, staring uncertainly from Blake to the angry girl, for once in his life utterly disconcerted and bewildered. He was unable to think, and the impulse of his breeding urged him to accompany Genevieve. After a moment's vacillation, he sprang about and hastened with her from the room.

Blake sat writhing in dumb anguish, his distended eyes fixed upon the doorway for many moments after they had gone. Then slowly yet as though drawn by an irresistible force, his gaze sank until it rested upon the half-filled wine glass left by Lord James. He glared at it in fearful fascination. Suddenly his hand shot out to clutch at it,—and as suddenly was drawn back.

There followed a grim and silent struggle, which ended in a second clutch at the glass. This time the shaking fingers closed on the slender stem. The wine was almost wetting his lips when, with a convulsive jerk, he flung it out upon the rug beside his chair.

Shuddering and quivering, Blake sank back in the chair, with his left arm upraised across his face as if he were expectant of a crushing blow or sought to shut out some horrible sight. His right arm slipped limply down outside the chair-arm, and the empty glass dropped to the floor out of his relaxing fingers.

Yet the lull in the contest was only momentary. As his protecting arm sank down again, his bloodshot eyes caught sight of the wine in Genevieve's glass. Instantly he started up rigid in his chair and clutched the edge of the table, as if to spring up and escape. But he could not tear his gaze away from the crimson wine.

Again there came the grim and silent struggle, and again the fierce craving for drink compelled his hand to go out to grasp the glass. But his will was not yet totally benumbed. As his fingers crooked to clutch the glass-stem, he made a last desperate effort to withstand the all but irresistible impulse that was forcing him over the brink of the pit. Beads of cold sweat started out on his forehead. His face creased with furrows of unbearable agony. His mouth gaped. The serpent had him by the throat.

The struggling man realized that he was on the verge of defeat. He was almost overcome. In a flash he perceived the one way to escape. For a single instant his slack jaw closed fast,—and in the same instant his outstretched hand clenched together and upraised and smashed down upon the wine glass.

Utterly exhausted, the victor collapsed forward, with head and arms upon the table, in a half swoon that quickly passed into the sleep-stupor of outspent strength.