"Right!" ejaculated Mortenson, rising. "But it will take ten days or more to build the instruments."

Steckel groaned. "Meanwhile the crook will keep on operating!" he said grimly. "The city will be at his mercy until the sets are finished. But I guess it can't be helped."

"No," said the scientist slowly, "it can't be helped."


IV

The Visitor

Days passed swiftly. Gold seemed to have become an obsession with the phantom bandit. The police were powerless. The crook robbed and killed at will, feeling safe and secure in his ability to swoop down and vanish, leaving the alert minions of the law baffled completely. In three days he had robbed four banks and escaped with his loot. He left death and fear behind him on each occasion. Then for a whole day he failed to appear, but Mortenson felt that he would return. And he did, the following day, to loot the city treasury of a quarter million dollars!

Then the rumbling of public protest echoed through the press. Chief Steckel and his department were at once swamped in a vortex of caustic sentiment. But the chief had been under fire before and remained silent, while the press made light of his ability to cope with the underworld forces, particularly with the phantom bandit. He was powerless and knew it, yet he kept secret his negotiations with Professor Mortenson. It would never do to allow that to get out! Before Mortenson could complete his apparatus, the phantom crook would swoop down upon him and kill him. What then? Chief Steckel was no fool, and he took the bitter dose without complaint.

The "Journal" boldly asked the mayor and the police commission to dismiss him. Steckel was called on the carpet and thoroughly denounced. Sentiment and unmerciful nagging were beginning to disrupt the whole department, a fine machine that he had built up for the protection of the people. He smiled grimly through it all, and finally asked for a fifteen day stay of removal. This was granted to him by the mayor despite the protests of the press and the commission. Steckel laughed secretly and told himself that there'd be a change of opinion at the end of fifteen days.

Meanwhile, Mortenson, with five expert opticians and three master mechanics under him, worked doggedly in his laboratory. The laboratory adjoined the scientist's big house where they consumed their meals hurriedly. Mortenson slept with the men a few hours each night in the workroom. Plain-clothes men lurked about the place as a precaution against a raid on the scientist by the vanishing criminal who, they suspicioned, might have learned through the grapevine system what was going on.