one o'clock
resumed the Tracer . `` Here you sit -- and there you are ! '' -LSB- Illustration : MR. KEEN 'S SKETCH OF THE RENDEZVOUS -RSB- `` Thanks , '' said Carden , laughing again . `` Now , '' continued the Tracer , `` you must be there at one o'clock . She will be there at one-thirty , or earlier perhaps . A little later I will become benignly visible . Your part is merely a thinking part ; you are to do nothing , say nothing , unless spoken to .