His devotion to physics seemed very unpractical to quiet Mrs. Gregg, who had set her heart on making a minister of her eldest son. She had named him John Paul, by way of having the names of two apostles ready for the future, and she had day-dreams of sitting in the front pew in church to hear him preach, while she looked up to him with wondering delight. It was a trial to be thinking of the Rev. John Paul Gregg, a tall, dignified and grave man, who was respected by everybody and had, perhaps, published a book of sermons, and then to have a freckled lad, round-faced and brown as a berry, with a scar across his forehead where an exploding crucible had just missed the eye, burst in upon her to beg her best preserving-kettle for an experiment. And to hear the future clergyman called “Fic” Gregg all over her end of the town made her shudder. Most of the people of Lavenham who knew him thought Specific Gravity mildly insane, but they all liked him. He was so simple and sincere and kind that they could not help it; but they never knew what he would be up to next in the line of dangerous experiment. He was as inventive as a fox, as spry as a cat, and as steady-headed as a monkey. Old Deacon Podgers looked out at his window one morning when it was blowing half a gale, and on the top of the unfinished steeple of the new Baptist Church saw a strange black object. The deacon, who had been a sea-captain all his active days, turned to the wall for his spy glass, and recognized Gravity Gregg, who had climbed up there to study the vibration of materials, as he told the deacon when he asked him why he risked his life so recklessly. John Paul acquired his name of Specific Gravity from an early answer in the philosophy class, but it did not become publicly his until one day after an anxious night in the big railroad freight-yards just outside the town. The Gregg house was on the brow of the hill overlooking the river and the flats where the railroad runs, and Fic knew every landmark visible from his window. It was a holiday. He had been fishing all day and went to bed early, but woke up about midnight with a start to see a flickering light reflected on the wall. He was at the window in a moment, and after taking an observation said to himself, “That’s in the freight-yards! It must be a car on fire!” It was not a big blaze, like a burning house, but a flickering little blaze, like that of the lamps on the fruit-peddlers’ stands at night. The desire to investigate was strong upon John Paul. His mother had never objected to his going to fires, but would she let him go so late at night? He would not wake her up to ask, and with a sigh went back to bed again and dropped off to sleep—only to be wakened up by the distant sound of a fire-engine rattling through the streets and to see the same flickering light at the same spot on the wall. He went to the window again and took the field-glass, which was one of his most cherished possessions.