"They know yagué," he heard himself saying coldly, "which makes any person obey any command. They may know other and more hellish ones yet."
He fought for self control, which meant the ability to conceal absolutely any form of shock that might await him. That one was in store he was certain. He paced grimly the length of the room and back again....
Something on the carpet caught his eye. A bit of string. He stared at it incredulously. The end was tied into a curious and an individual knot, which looked like it might be the pastime of a sailor, and which looked like it ought to be fairly easy to tie. But it was one of those knots which wandering men sometimes tie absent mindedly in the presence of stirring events. It was the recognition-knot of the Trade, one of those signs by which men may know each other in strange and peculiar situations. And there were many other knots tied along the trailing length of the string. It seemed as if some nervous and distraught prisoner in this room might have toyed abstractedly with a bit of cord.
Only, Bell drew it through his fingers. Double knot, single knot, double knot.... They spelled out letters in the entirely simple Morse code of the telegrapher, if one noticed.
"RBRA GN ON PLA HRE ST TGT J."
Your old-time telegrapher uses many abbreviations. Your short-wave fan uses more. Mostly they are made by a simple omission of vowels in normal English words. And when the recognition sign at the beginning was considered, the apparently cryptic letters leaped into meaning.
"RiBeRA GoNe ON PauLA HeRe SiT TiGhT Jamison."
When the door opened again and a terribly pale Paula was ushered in, Bell gave no sign of surprise. He simply took her in his arms and kissed her, holding her very, very close.