“Maw used ter give me sarsaparilla,” said Jimmie.

“My folks,” observed Pete, “never tuk nothin’ but castor ile.  Must ha’ downed a barrel o’ that when I was a kid.”

“This thing is drivin’ me crazy,” said Dan.

“Wal,” replied Pete deliberately, “I know what I’d do, and I’d do it quick.  This yere Professor is on the ranch, and he’s a dandy.  After the rodeo, you jest sachay up to him an’ tell him what you’ve tole us.  If he don’t take the kinks outer yer, he’s a fraud.  See!”

“Gosh,” exclaimed Dan, “I’ll do it!”

They turned in.

* * * * *

The Professor next day watched the rodeo from a platform erected near the biggest of our corrals.  This was his first visit to California, and he was mightily impressed by the skill and vigour of the vaqueroes.  To Ajax he declared that he was amazed to find such splendid specimens in that particular locality.  Ajax smiled.

“We have not much,” he said, “but we feel that we have a right to expect high health.  We used to say,” he added, “that sickness was unknown in our hills till a wise doctor settled here from the East.”

The Professor frowned.

“I rose at six,” he said austerely.  “I made a microscopical examination of the water in your new spring, which rises, I venture to remind you, through soil which is undoubtedly diatomaceous.”

“That sounds awful.”

“Diatoms in a fossilised condition are silicious, and they are to be found in Virginia, in Bermuda, and here.”

“Professor, I am an ignoramus.”

“Then it is my duty to inform you that the man or woman who drinks water from that spring is swallowing millions of tiny flint knives, hard as diamond dust—­indeed, diatomaceous earth is used commercially as a polishing powder.”

“You mean that if we drink that water we shall be polished off?”

The Professor glared.  Like many distinguished scientists, he took himself seriously, and he knew that this was a serious matter.

“Those tiny flint knives cut to ribands the mucous membrane.”

“Fortunately,” said Ajax, “we don’t drink that water.  The spring was only developed a few days ago.”  In a graver voice he continued:  “We are exceedingly obliged to you.  Of course we shall warn our men.”

“Has nobody drunk of that spring?”

Ajax thought that he detected a note of disappointment.  He replied reflectively:  “I don’t think so.  The cattle have used it.  It doesn’t seem to have affected them.”

“Are you sure of that?” he demanded sharply.

“You can ask our foreman.”

Later, the Professor did so.  Uncle Jake came out of the corrals, carrying a branding-iron and found himself confronted by a short, thick-set man with prominent, slightly congested grey eyes, which shone keenly out of an immense head.

“I am Professor Chawner, of the Smithsonian.  I wish to ask you a question.”