At Thirty-Fourth street the line was held up again. The whistle had just blown, and this promised to be a longer stoppage. Jack jumped out of the taxi, and ran ahead down the line with fast beating heart.
The black limousine was empty.
Jack gritted his teeth. "The devil's own luck favors him," he thought. "They must have left the car during the block on Forty-Second."
The chauffeur had not seen him. Jack did not approach him, thinking it better to take a chance of following him to his garage. The line got in motion again, and Jack swung himself aboard his taxi as it passed.
At Twenty-Eighth street the whistle blew just as the black car was crossing. It continued blithely down the avenue, the chauffeur waggling a derisive hand outside his car. Jack would have risked defying the whistle, but his way was effectually blocked by other cars in front and on both sides.
"My luck again!" he groaned.
They were held up there while a ten-horse truck bearing a steel girder crawled across the Avenue. When the whistle gave them leave to move again, the limousine had disappeared into a side street. They saw it no more.
Jack had the license number, but an investigation instituted by telegraph only proved as he expected, that that number had been issued to some one giving a mythical address in Atlanta. As for notifying the New York police, he knew very well that within half an hour the license tags on the black limousine would be changed.