six o'clock
`` H 'm , '' observed Curtis , reading the despatch . `` What next ? '' `` He 'll fulfil his threat . To-morrow evening at six o'clock he will stop the vibrations either of light , of electricity , or of sound -- probably of electricity , as he has appointed the rush hour . '' `` Most likely , '' Curtis agreed . `` Warn the people to keep out of the subways , and not to get scared . Take it easy .