"Nonsense!" retorted Reade, retaining a strong clutch on the boy's shoulder, though once more the sound reached their ears.

"It's all your nerves, Alf," Tom insisted. "You just imagine such things. That's what cigarettes do to your nerves."

"But don't you hear the rattlesnake?"

"I don't," Tom gravely informed him, though once more the nerve-disturbing sound rose clearly on the air. "See here, Alf, rattlers, whatever their habits, certainly don't climb trees. I'll put you up on that limb."

Tom's strong young arms lifted Alf easily until he could clutch at the lowest limb of a tree.

"Climb up there and sit down," Reade ordered. Drew sat on the limb, shaking with terror.

"Now, I'll show you that there isn't a snake anywhere in that clump of brush," Tom proposed, and forthwith stepped into the thicket, beating about lustily with his heavy boots.

"L-l-l-look out!" shivered Drew. "You'll be bitten!"

"Nonsense, I tell you. There isn't a rattler anywhere on this part of the Range. It's your nerves, Alf. Cigarettes are destroying 'em. There! I've beaten up every bit of this brush and you see that I've not been bitten. Now I'll help you down to the ground, and you want to get a good, steadying grip on your nerves."

Alf Drew permitted himself to be helped to the ground. No sooner, however, had his feet touched the earth than there came that ominous rattling sound.

"There, you big idiot!" howled Alf. "There it is again!"

"Just your bad nerves, Alf," Tom smiled. "They're so bad that I'll overlook your lack of respect calling me an idiot!"

"Don't you s'pose I know rattlers when I hear 'em?" asked Drew, sullenly. "I was almost bitten by one once, and that's why I'm so afraid of 'em."

"I was bitten once," Tom replied. "Yet you see that I'm not very nervous about them, especially in a part of the country where none are ever found. It's your nerves, Alf—-and cigarettes!"

"I wish I had one now," sighed the younger boy.

"A rattlesnake?" Tom inquired innocently.

"No—-of course not! A cigarette."

"But you're going to forget those soul-destroying little coffin-nails,"
Reade suggested. "You're going to become a man and act like one.
You're going to learn how much more fun it is to have your lungs
filled with pure air instead of stifling cigarette smoke."

"Maybe I am!" muttered the boy.

"Oh, yes; I'm sure of it," said Reade cheerfully.

Cl-cl-cl-click!

"O-o-o-ow!" shrilled Alf, jumping at least two feet.

"Now, what's the matter with you?" inquired Tom in feigned astonishment.

"Don't tell me you didn't hear the rattler just now," cried young
Drew fiercely.

"No; I didn't," Tom assured him. "And how could we find a rattler—here? We're crossing open ground now. There is no place within three hundred feet of us for a rattlesnake to move without our seeing him."

Cl-cl-cl-click!

Alf Drew held back, trembling.

"I'm not going forward another step," he insisted. "This ground is full of rattlers."

"Let's go back to camp, then, if your nerves are so unstrung,"
Reade proposed.

They turned, starting backward. Again the warning rattle sounded, seemingly just in front of Alf, though there was no place for a snake to conceal itself nearby.

Alf, however, turned paler still, halted and started off at right angles to his former course. Again the rattle sounded.

"Hear that snake?" demanded young Drew.

"No; and there isn't one," Tom assured him. "Why will you be so foolish—-so nervous? In other words, why do you destroy your five senses with cigarettes in this fashion?"

Cl-cl-click!

Alf Drew halted, trembling so that he could hardly stand.

"I'm going to quit camp—-going to get out of this place," he shivered. "The ground is full of rattlers. O-o-o-oh! There's another tuning up."

Tom laughed covertly. The disturbing sound came again.

"I never saw a place like this part of the range," Alf all but sobbed, his breath catching. "Oh, won't I be glad to see a city again!"

"Just so you can find a store where you can buy cigarettes?" Tom
Reade queried.

"I wish I had one, now," moaned the young victim. "It would steady me."

"The last ones that you smoked didn't appear to steady you," the young engineer retorted. "Just see how unstrung you are. Every step you take you imagine you hear rattlers sounding their warning."

"Do you tell me, on your sacred honor," proposed Alf, "that you haven't heard a single rattler this afternoon?"

"I give you my most solemn word that I haven't," Tom answered. "Come, come, Alf! What you want to do is to shake off the trembles. Let me take your arm. Now, walk briskly with me. Inflate your chest with all the air you can get in as we go along. Just wait and see if that isn't the way to shake off these horrid cigarette dreams."

Something in Reade's vigorous way of speaking made Alf Drew obey. Tom put him over the ground at as good a gait as he judged the cigarette victim would be able to keep up.

Readers of the preceding volumes of this series, and of other, earlier series, need not the slightest introduction to Tom Reade and Harry Hazelton. Our readers of the "Grammar School Series" know Tom and Harry as two of the members of that famous sextette of schoolboy athletes who, under the leadership of Dick Prescott, were known as Dick & Co.

In the "High School Boys Series," too, our readers have followed the fortunes of Tom Reade and Harry Hazelton, through all their triumphs on football fields, on baseball diamonds and in all the school sports.

Dick Prescott and Greg Holmes succeeded in winning appointments to the United States military Academy, and their adventures are fully set forth in the "West Point Series."

Dave Darrin and Dan Dalzell "made" the United States Naval Academy at Annapolis, and what befell them there has been fully set forth in the "Annapolis Series."

Reade and Harry Hazelton elected to go through life as civil engineers. In "The Young Engineers in Colorado" has been fully set forth the extraordinary work of these young men at railroad building through the mountains wilds. In "The Young Engineers in Arizona" we have followed Tom and Harry through even more startling adventures, and have seen how they handled even greater problems in engineering.

Up to date the careers of these two bright young men had not been humdrum ones. The surroundings in which their professional lives had been passed had been such as to supply them with far more startling adventures than either young man had ever looked for.

And now they were in Nevada, the state famous for its gold and silver mines. Yet they had come ere solely in search of a few weeks of rest. Rest? There was anything but rest immediately ahead of the young engineers, but the curtain had not been lifted.

Immediately after the completion of their great work in Arizona, Tom Reade and Harry Hazelton had gone back east to the good old home town of Gridley. While there they had encountered Dick Prescott and Greg Holmes, their old school chums, at that time cadets at the United