but i must waste no more time , uncertain , as i am , how many minutesbreathless with alarmor even secondsfilled with the rapid beating of my hearti may have before those ominous steps halt outside the door , the knob turns within the grasp of my abductors hand , and the heavy panel swings open to reveal the stern lines of that most terrifying visage but no , it was only nell , come to advise me that a mrs. thingumbob has called unexpectedly , and since my mother would not , therefore , be able to go out as soon as she had intended , i might return to the garden if i so wished .