"Yes, sir," ventured Herzog. "There are three processes to extract nitrogen and oxygen from air. One is by means of what the German scientists call Kalkstickstoff, between calcium carbide and nitrogen, and the reaction-symbols are—"
"No matter," Flint waived him, promptly. "I don't care for formulas or details. What I want is results and general principles. Any other way to extract these substances, in commercial quantities, from the air we breathe?"
"Two others. But one of these operates at a prohibitive cost. The other—"
"Yes, yes. What is it?" Flint slid off the edge of the table and walked over to Herzog; stood there in front of him, and bored down at him with eager eyes, the pupils contracted by morphine, but very bright. "What's the best way?"
"With the electric arc, sir," answered the chemist, mopping his brow. This grilling method reminded him of what he had heard of "Third Degree" torments. "That's the best method, sir."
"Now in use, anywhere?"
"In Notodden, Norway. They have firebrick furnaces, you understand, sir, with an alternating current of 5000 volts between water-cooled copper electrodes. The resulting arc is spread by powerful electro-magnets, so." And he illustrated with his eight acid-stained fingers. "Spread out like a disk or sphere of flame, of electric fire, you see."
"Yes, and what then?" demanded Flint, while his partner, forgetting now to smile, sat there by the window scrutinizing him. One saw, now, the terribly keen and prehensile intellect at work under the mask of assumed foppishness and jesting indifference—the quality, for the most part masked, which had earned Waldron the nickname of "Tiger" in Wall Street.
"What then?" repeated Flint, once more levelling that potent forefinger at the sweating Herzog.
"Well, sir, that gives a large reactive surface, through which the air is driven by powerful rotary fans. At the high temperature of the electric arc in air, the molecules of nitrogen and oxygen dissociate into their atoms. The air comes out of the arc, charged with about one per cent. of nitric oxide, and after that—"