Whatever other steps Nell might take in the time she had left, there was 
one thing she could do quickly and easily here. She was not entirely sure why 
she did it, but some intuition told her that it might be useful; or perhaps it 
was an artistic urge to make something that would live longer than she would, 
even if only by a few minutes. She began by erasing all of the big advertising 
panels on the upper levels of the skyscraper. Then she sketched out a simple 
line drawing in primary colors: an escutcheon in blue, and within it, a crest 
depicting a book drawn in red and white; crossed keys in gold; and a seed in 
brown. She caused this image to be displayed on all sides of the skyscraper, 
between the hundredth and two-hundredth floors.