The form which the lamp finally took in the hands of Mr. Newman, the instrument-maker, is seen on p. 200.
The trials above referred to were first made by Mr. Matthias Dunn and the indefatigable Mr. Hodgson in the Hebburn Colliery, and shortly afterwards by Mr. John Buddle in the Wall’s End Colliery. Mr. Buddle has placed on record his impressions of his first experience.
“I first tried it,” he says, “in an explosive mixture on the surface; and then took it into a mine; ... it is impossible for me to express my feelings at the time when I first suspended the lamp in the mine and saw it red hot.... I said to those around me ‘We have at last subdued this monster.’”
Some months afterwards Davy accompanied Mr. Buddle into the pit and saw his lamp in actual use.
“Sir Humphry was delighted,” says Mr. Buddle, “and I was overwhelmed with feelings of gratitude to that great genius which had produced it.”
Further testimony of Mr. Buddle’s appreciation of this memorable invention may be seen from the following extract from a letter by him to Davy. It is not only interesting in view of Davy’s remark that “the evidence of the use of a practical discovery is of most value when furnished by practical men,” but also as showing the rapidity with which the discovery was taken advantage of:--
“Walls End Colliery, Newcastle, _June 1st, 1816_.
“After having introduced your safety lamp into general use in all the collieries under my direction, where inflammable air prevails, and after using them daily in every variety of explosive mixture, for upwards of three months, I feel the highest possible gratification in stating to you that they have answered to my entire satisfaction.
“The safety of the lamps is so easily proved by taking them into any part of a mine charged with fire-damp, and all the explosive gradations of that dangerous element are so easily and satisfactorily ascertained by their application, as to strike the minds of the most prejudiced with the strongest conviction of their high utility; and our colliers have adopted them with the greatest eagerness.
“Besides the facilities afforded by this invention to the working of coal mines abounding in fire-damp, it has enabled the directors and superintendents to ascertain, with the utmost precision and expedition, both the presence, the quantity, and the correct situation of the gas. Instead of creeping inch by inch with a candle, as is usual, along the galleries of a mine suspected to contain fire-damp, in order to ascertain its presence, we walk firmly in with the safe lamps, and with the utmost confidence prove the actual state of the mine. By observing attentively the several appearances upon the flame of the lamp, in an examination of this kind, the cause of accidents which have happened to the most experienced and cautious miners is completely developed; and this has been, in a great measure, matter of mere conjecture.