The man of science melted.  With a shrug of his massive shoulders, he said, mildly for him—­

“My dear sir, I will try to gratify a not unreasonable curiosity.  I did not wish to alarm you prematurely this morning, but the worst has happened.  The silicious fragments in that confounded earth have lacerated terribly the mucous membranes of these three unfortunate young men.  That in itself is a matter of small importance.  The mucous membrane is most delicate, but it has quite amazing capacities of repairing itself.  The point is this.  The water in that spring, and—­ I’ll be perfectly frank—­the water in most of the surface springs in this particular locality, is simply swarming with pathogenic germs, and amongst them I identified this morning the as yet unnamed coccus which I had the honour to discover, and which is as deadly as the coma bacillus of Asiatic cholera, or—­shall I say?—­the highly specialised venom of the rattlesnake.”

“Great Scot!”

“This coccus, my dear friend, increases and multiplies under certain conditions.  It exacts a highly lacerated condition of the mucous membrane into which it burrows.  Fortunately it is rare; fortunately, also, it is seldom found in water which has filtered through diatomaceous earth; for these fossilised deposits are only found here and there, and, as a rule, not near water.”

“They are three good fellows.”

“I hope to pull them through,” said the Professor stoutly.  “For the moment there is nothing more to be done.  They are in bed, and, not to put a fine point on it, half-drunk.  Alcohol stupefies the cocci, but it does not destroy them.  I shall pour whisky down their throats till the drugs I have ordered arrive from San Lorenzo.  I have told your foreman that my patients are not to be disturbed.  After supper I shall administer another dose of whisky.”

An hour later, the Professor, accompanied by me, returned to the bunk-house.

“I hope to find them asleep,” he said.  “I gave them enough alcohol to induce stupor.”

“How much?”

“At least a quart.”

I said with deference—­

“I do not presume to question your treatment, but cowboys can carry an amazing quantity of whisky.  Alcohol is a stimulant-narcotic, isn’t it?”

“Perfectly.”

“It stimulates first.  Speaking from a variegated experience of cowboys, I should say that a quart of well-matured Bourbon would barely suffice to stimulate three powerful young men.”

“’Um!” said the Professor thoughtfully.  “I had not considered that.  They assured me they were water-drinkers.  However, a mistake of that sort is easily rectified.”

So speaking, he tiptoed to the door of the bunk-house, and, finger upon lips, entered.  Immediately a sharp exclamation indicated that something surprising had occurred.  I followed quickly, to find the Professor staring, pop-eyed, at three vacant bunks.