But even this did not stand scrutiny.

If he had failed to persuade Frank to remain in Cambridge, it was improbable that he could succeed in persuading him to return--even if he found him.

About eight important roads run out of Cambridge, and he had not a glimmer of an idea as to which of these he had taken.

It was possible, even, that he had not taken any of them, and was walking across country.

That would be quite characteristic of Frank.
* * * * * He finished breakfast dismally, and blew through an empty pipe, staring lackadaisically out of the window at the wall of Sidney Sussex for two or three minutes before lighting up.