"Good Lord!" I breathed.

A care-worn smile crept into his eyes. "A test for nerves, you think, Mr. Gilland? I agree with you. n.o.body fears what anybody can see."

There came the slightest movement beside me.

"Are you trembling?" I asked, turning.

"I was writing," she replied, steadily. "Did my elbow touch you?"

"By-the-way," said Professor Farrago, "I fear I forgot to congratulate you upon your choice of a stenographer, Mr. Gilland."

A rosy light stole over her pale face.

"Am I to record that too?" she asked, raising her blue eyes.

"Certainly," he replied, gravely.

"But, professor," I began, a prey to increasing excitement, "do you propose to attempt the capture of one of these animals?"

"That is what the cage is for," he said. "I supposed you had guessed that."

"I had," murmured the pretty stenographer.

"I do not doubt it," said Professor Farrago, gravely.

"What are the chemicals for--and the tank and hose attachment?"

"Think, Mr. Gilland."

"I can't; I'm almost stunned by what you tell me."

He laughed. "The rosium oxide and salts of strontium are to be dumped into the tank together. They'll effervesce, of course."

"Of course," I muttered.

"And I can throw a rose-colored spray over any object by the hose attachment, can't I?"

"Yes."

"Well, I tried it on a transparent jelly-fish and it became perfectly visible and of a beautiful rose-color: and I tried it on rock-crystal, and on gla.s.s, and on pure gelatine, and all became suffused with a delicate pink glow, which lasted for hours or minutes according to the substance.... Now you understand, don't you?"

"Yes; you want to see what sort of creature you have to deal with."

"Exactly; so when I've trapped it I am going to spray it." He turned half humorously towards the stenographer: "I fancy you understood long before Mr. Gilland did."

"I don't think so," she said, with a sidelong lifting of the heavy lashes; and I caught the color of her eyes for a second.

"You see how Miss Barrison spares your feelings," observed Professor Farrago, dryly. "She owes you little grat.i.tude for bringing her here, yet she proves a generous victim."

"Oh, I am very grateful for this rarest of chances!" she said, shyly.

"To be among the first in the world to discover such wonders ought to make me very grateful to the man who gave me the opportunity."

"Do you mean Mr. Gilland?" asked the professor, laughing.

I had never before seen Professor Farrago laugh such a care-free laugh; I had never suspected him of harboring even an embryo of the social graces. Dry as dust, sapless as steel, precise as the magnetic needle, he had hitherto been to me the mummified embodiment of science militant. Now, in the guise of a perfectly human and genial old gentleman, I scarcely recognized my superior of the Bronx Park society. And as a woman-hater he was a miserable failure.

"Heavens," I thought to myself, "am I becoming jealous of my revered professor's social success with a stray stenographer?" I felt mean, and I probably looked it, and I was glad that telepathy did not permit Miss Barrison to record my secret and unworthy ruminations.

The professor was saying: "These transparent creatures break off berries and fruits and branches; I have seen a flower, too, plucked from its stem by invisible digits and borne swiftly through the forest--only the flower visible, apparently speeding through the air and out of sight among the thickets.

"I have found the footprints that I described to you, usually on the edge of a stream or in the soft loam along some forest lake or lost lagoon.

"Again and again I have been conscious in the forest that unseen eyes were fixed on me, that unseen shapes were following me. Never but that one time did these invisible creatures close in around me and venture to touch me.

"They may be weak; their structure may be frail, and they may be incapable of violence or harm, but the depth of the footprints indicates a weight of at least one hundred and thirty pounds, and it certainly requires some muscular strength to break off a branch of wild guavas."

He bent his n.o.ble head, thoughtfully regarding the design on his slippers.

"What was the rifle for?" I asked.

"Defence, not aggression," he said, simply.

"And the camera?"

"A camera record is necessary in these days of bad artists."

I hesitated, glancing at Miss Barrison. She was still writing, her pretty head bent over the pad in her lap.

"And the clothing?" I asked, carelessly.

"Did you get it?" he demanded.

"Of course--" I glanced at Miss Barrison. "There's no use writing down everything, is there?"

"Everything must be recorded," said Professor Farrago, inflexibly.

"What clothing did you buy?"

"I forgot the gown," I said, getting red about the ears.

"Forgot the gown!" he repeated.

"Yes--one kind of gown--the day kind. I--I got the other kind."

He was annoyed; so was I. After a moment he got up, and crossing to the log cabin, opened one of the boxes of apparel.

"Is it what you wanted?" I inquired.

"Y-es, I presume so," he replied, visibly perplexed.