er a space of five hundred yards, were extinguished
almost instantaneously; whereas the Davy lamps were filled with fire, and
became red-hot--so much so, that several of the men using them had their
hands burnt by the gauze. Had a strong current of air been blowing
through the gallery at the time, an explosion would most probably have
taken place--an accident which, it will be observed, could not, under
such circumstances, occur from the use of the Geordy, which is
immediately extinguished as soon as the air becomes explosive. {107}

Nicholas Wood, a good judge, has said of the two inventions, "Priority
has been claimed for each of them--I believe the inventions to be
parallel. By different roads they both arrived at the same result.
Stephenson's is the superior lamp. Davy's is safe--Stephenson's is
safer."

When the question of priority was under discussion at the studio of Mr.
Lough, the sculptor, in 1857, Sir Matthew White Ridley asked Robert
Stephenson, who was present, for his opinion on the subject. His answer
was, "I am not exactly the person to give an unbiassed opinion; but, as
you ask me frankly, I will as frankly say, that if George Stephenson had
never lived, Sir Humphry Davy could and most probably would have invented
the safety-lamp; but again, if Sir Humphry Davy had never lived, George
Stephenson certainly would have invented the safety-lamp, as I believe he
did, independent of all that Sir Humphry Davy had ever done in the
matter."

[Picture: West Moor Pit, Killingworth]

CHAPTER VII.
GEORGE STEPHENSON'S FURTHER IMPROVEMENTS IN THE LOCOMOTIVE--THE HETTON
RAILWAY--ROBERT STEPHENSON AS VIEWER'S APPRENTICE AND STUDENT.

Stephenson's experiments on fire-damp, and his labours in connexion with
the invention of the safety-lamp, occupied but a small portion of his
time, which was necessarily devoted for the most part to the ordinary
business of the colliery. From the day of his appointment as
engine-wright, one of the subjects which particularly occupied his
attention was the best practical method of winning and raising the coal.
He was one of the first to introduce steam machinery underground with the
latter object. Indeed, the Killingworth mines came to be regarded as the
models of the district; the working arrangements generally being
conducted in a skilful and efficient manner, reflecting the highest
credit on the colliery engineer.

Besides attending to the undergrou