Part,  Chapter

 1 1,1|        It cannot be more than 500 feet from us!" "Overboard
 2 1,1|  atmosphere, to a height of 4,500 feet. The voyagers, after
 3 1,1|    clock the balloon was only 500 feet above the surface of
 4 1,1|      mounted to a height of 1,500 feet, and here it met a
 5 1,0|  appeared to him to measure 3,500 feet above the level of
 6 1,4|   following proportions:-~ 15:500::10:x ~ 500 x 10 = 5000 ~
 7 1,4| proportions:-~ 15:500::10:x ~ 500 x 10 = 5000 ~ 5000 / 15 =
 8 3,2| penitentiaries. They numbered 500, under an iron discipline,
 9 3,5|    had risen. The surf roared 500 feet below. ~Harding calculated
10 3,5|  Mammoth caverns in Kentucky, 500 feet in height, and more