Chapter XI (2)

In reasoning upon these several phenomena, it occurred to him, that as a high temperature was required for the inflammation of the fire-damp, and as it produced in burning, comparatively, _a small degree_ of heat, the effect of carbonic acid and azote, as well as that of the surfaces of small tubes, in preventing its explosion, depended upon their cooling powers; that is to say, upon their lowering the temperature of the exploding mixture to such a degree, that it was no longer sufficient for its continuous inflammation. In support of this theory, he ascertained that metallic tubes resisted the passage of the flame more powerfully than glass tubes of similar lengths and diameters, metal being the better conductor of heat; and that carbonic acid was more effective than azote in depriving the fire-damp of its explosive power, in consequence, as he considered, of its greater capacity for heat, and likewise of a higher conducting power connected with its greater density.

In this short statement, the reader is presented with the whole theory and operation of the Safety-lamp, which is nothing more than an apparatus by which the inflammable air, upon exploding in its interior, cannot pass out without being so far cooled, as to deprive it of the power of communicating inflammation to the surrounding atmosphere. The principle having been once discovered, it was easy to adopt and multiply practical applications of it.

From the result of these researches, it became at once evident, that to light mines infested with fire-damp, with perfect security, it was only necessary to use an air-tight lantern, supplied with air from tubes of small diameter, through which explosions cannot pass, and with a chimney, on a similar principle, at the upper part, to carry off the foul air. A common lantern, to be adapted to the purpose, merely required to be made air-tight in the door and sides, and to be furnished with the chimney, and the system of safety apertures below and above the flame of the lamp. Such, in fact, was Davy's first Safety-lamp; and having afterwards varied the arrangement of the tubes in different ways, he at length exchanged them for canals, which consisted of close concentric hollow metallic cylinders of different diameter, so placed together as to form circular canals of the diameter of from one-twenty-fifth to one fortieth of an inch; and of an inch and seven-tenths in length; by which air is admitted in much larger quantities than by the small tubes, and they are moreover much superior to the latter in practical application. He also found, that longitudinal air-canals of metal might be employed with the same security as circular canals; and that a few pieces of tin plate, soldered together with wires to regulate the diameter of the canal, answered the purpose of the feeder or safe chimney, as well as drawn cylinders of brass.

The subjoined explanatory sketches will assist in rendering the scheme intelligible, and obviate the possibility of any misconception of the subject.

FIG. 1. represents the first Safe lantern, with its air-feeder and chimney furnished with safety metallic canals. The sides are of horn or glass, made air-tight by putty or cement. A. is the lamp through which the circular air-feeding canals pass. B. is the chimney containing four such canals; above it is a hollow cylinder, with a cap to prevent dust from passing into the chimney. C. is the hole for admitting oil. F. is the rim round the bottom of the lantern, to enable it to bear motion.

FIG. 2. exhibits an enlarged view of the safety concentric canals, which, if one-twenty-fifth of an inch in diameter, must not be less than two inches in exterior circumference, and one-seventh of an inch high.

FIG. 3. exhibits the longitudinal safety canals.

FIG. 4. represents a Safety-lamp having a glass chimney, covered with tin-plate, and the safety apertures in a cylinder with a covering above: the lower part is the same as in the lantern.

FIG. 5. A glass tube furnished with _flame sieves_, in which a common candle may be burnt. A A. the flame sieves. B. a little plate of metal to prevent the upper flame sieve from being acted on by the current of hot air.

During the short visit of Sir Humphry Davy at Bishop Wearmouth, he saw the lamp which Dr. Clanny was then engaged in perfecting. It has been already observed, that it was secured against the effects of fire-damp by being supplied with atmospheric air previously conveyed through water.[34] The machinery of this lamp was far too cumbrous to be of general use; but its inventor was justly commended by Davy for his ingenuity and perseverance. It unfortunately happened that, in consequence of some erroneous representations made to Dr. Clanny, he received the impression that Sir Humphry had not been disposed to treat his invention with sufficient respect, nor had given him the credit to which he was so justly entitled. This suspicion, which had been long industriously kept alive, was however ultimately removed.

[34] M. de Humboldt conceived and executed the plan of a lamp in
1796, for giving a safe light in mines, upon a similar principle
of entire insulation from the air.--_Journal des Mines_, t. viii.
p. 839.

The following letter refers to this unfortunate circumstance. I have adverted to it in these memoirs, for the purpose of showing what an unfair spirit of rivalry, and what a succession of petty jealousies were excited by those generous and disinterested labours of Davy, which ought to have called forth nothing but the most lively expressions of gratitude for his services, and admiration of his genius.

TO THE REVEREND DR. GRAY.

23, Grosvenor Street, December 13.

MY DEAR SIR,

A Friend of mine has sent me a newspaper--the Tyne Mercury,
containing a very foolish libel upon me. It states, amongst
other things, that I did not mention Dr. Clanny, or his lamp,
in my late paper read before the Royal Society; whereas I
mentioned his lamp as a very ingenious contrivance, and named
him amongst the gentlemen who obligingly furnished me with
information upon the subject.

It will be needless for me to point out to you that my lamp
has no one principle in common with that of Dr. Clanny. He
forces in his air through water by bellows. In mine, the air
passes through safety canals without any mechanical assistance.
Mine is a common lantern made close, and furnished with safety
canals.

I hope I shall not hear that Dr. Clanny has in any way
authorized or promoted so improper a statement as that in the
Tyne Mercury; indeed, I do not think it possible.

I have at last obtained a complete model of my lamp, after many
disappointments from the instrument-maker. I hope in a few days
to send you a _Safe lantern_, as portable as a common-made one,
and the perfect security of which is demonstrable.

I am, my dear Sir, your sincerely obliged,
H. DAVY.

TO THE SAME.

Grosvenor Street, December 15.

MY DEAR SIR,

I shall inclose the first sheet of my paper, and shall be glad
to preface it by some observations when you reprint it.

I shall forward my lanterns and lamps to you in a few days.
They are _absolutely_ safe; and if the miners have any more
explosions from their light, it will be their own fault.

You will find, when you see my construction, that the
principles as well as the execution are entirely new.

You will find in the second sheet of my paper, which I hope to
be able to send to-morrow, the _principles_ of _security_, and
its limits unfolded.

I am, my dear Sir, very sincerely yours,

H. DAVY.

TO THE SAME.

London, January 1, 1816.

MY DEAR SIR,

I fear you will have accused me of procrastination in delaying
to send you my papers and my lamps.

The papers read to the Royal Society have been printed; but
during the period that has elapsed since I last wrote to you,
I have made a discovery much more important than those which I
have already had the honour of communicating to you.

I have made very simple and economical lanterns, and candle
guards, which are not only _absolutely safe_, but which give
light by means of the fire-damp, and which, while they disarm
this destructive agent, make it useful to the miner.

This discovery is a consequence of that which I communicated
to you in my last letter on the wire sieves. I hope to be able
to send you on Wednesday the printed account of my results,
together with models of lamps which will burn and consume all
explosive mixtures of the fire-damp.

I have at last finished my enquiries with perfect satisfaction
to myself, and I feel highly obliged to you for having called
my attention to a subject where my labours will, I hope, be of
some use.

I am, my dear Sir, very sincerely yours,

H. DAVY.

It is impossible to approach the consideration of this last, the most signal and splendid of his triumphs, without feelings of the highest satisfaction. He had already, as we have seen, disarmed the fire-damp of its terrors, it only remained for him to enlist it into his service. The simple means by which this was effected are as interesting as their results are important.[35]

[35] "An Account of an Invention for giving Light in explosive
mixtures of Fire-damp in Coal Mines, by consuming the Fire-damp."
Read before the Royal Society, Jan. 11, 1816.

Davy had previously arrived at the fact, that wire-gauze might be substituted as air-feeders to the lamp, in the place of his tubes or safety canals; but not until after the lapse of several weeks, did the happy idea of constructing the lamp entirely of wire-gauze occur to him:--the history of this elaborate enquiry affords a striking proof of the inability of the human mind to apprehend simplicities, without a process of complication which works as the grappling machinery of truth.

His original lamp with tubes or canals, as already described, was perfectly safe in the most explosive atmosphere, but its light was necessarily extinguished by it; whereas in the wire-gauze cage, the fire-damp itself continues to burn, and thus to afford to the miner a useful light, while he is equally secured from the fatal effects of explosion.

All then required for his guidance and protection in the darkness of the mine, are candles or lamps surrounded by small wire cages, which will at once supply air to the flame, and light to the miner; they may be obtained for a few pence, and be variously modified as circumstances may render necessary.

The reader is here presented with a sketch of the gauze instrument, in its first and simplest form. The original lamp is preserved in the laboratory of the Royal Institution.

Nothing now remained but to ascertain the degree of fineness which the wire-gauze ought to possess, in order to form a secure barrier against the passage of flame. For this purpose, Davy placed his lighted lamps in a glass receiver, through which there was a current of atmospherical air, and by means of a gasometer filled with coal gas, he made the current of air which passed into the lamp more or less explosive, and caused it to change rapidly or slowly at pleasure, so as to produce all possible varieties of inflammable and explosive mixtures; and he found that iron wire-gauze composed of wires from one-fortieth to one-sixtieth of an inch in diameter, and containing twenty-eight wires, or seven hundred and eighty-four apertures to the inch, was safe under all circumstances in atmospheres of this kind; and he consequently employed that material in guarding lamps for the coal mines, where, in January 1816, they were immediately adopted, and have long been in general use.

Observations upon them in their working state, and upon the circumstances to which they are exposed, have led to a few improvements or alterations, merely connected with the modes of increasing light or diminishing heat, which were obvious from the original construction.

The annexed woodcut represents the lamp which is in present use. A is a cylinder of wire-gauze, with a double top, securely and carefully fastened, by doubling over, to the brass rim B, which screws on to the lamp C. The whole is protected by strong iron supports D, to which a ring is affixed for the convenience of carrying it.

In a paper read before the Royal Society, on the 23rd of January 1817, entitled, "Some new Experiments and Observations on the Combustion of Gaseous Mixtures, with an Account of a method of preserving a continued Light in mixtures of inflammable Gases and Air without Flame," Sir H. Davy announces the application of a principle which he had discovered in the progress of his researches for increasing the utility of the Safety-lamp, and which, a century ago, would have unquestionably exposed its author to the charge of witchcraft.

Having ascertained that the temperature of flame is infinitely higher than that necessary for the ignition of solid bodies, it appeared to him probable that, in certain combinations of gaseous bodies, although the increase of temperature might not be sufficient to render the gaseous matters themselves luminous, they might nevertheless be adequate to ignite solid matters exposed to them. During his experiments on this subject, he was led to the discovery of the curious phenomenon of slow combustion without flame. He observes, that there cannot be a better mode of illustrating the fact, than by an experiment on the vapour of ether or of alcohol. Let a few coils of wire of platinum of the one-sixtieth or one-seventieth of an inch be heated by a hot poker or candle, and let it be brought into the glass; it will presently become glowing, almost white hot, and will continue so, as long as a sufficient quantity of vapour and of air remain in the glass.[36]

[36] This principle has been applied for constructing what has
been termed the _Aphlogistic Lamp_, which is formed by placing
a small coil of platinum wire round the wick of a common spirit
lamp. When the lamp, after being lighted for a few moments,
is blown out, the platinum wire continues to glow for several
hours, as long as there is a supply of spirit of wine, and to
give light enough to read by; and sometimes the heat produced
is sufficient to rekindle the lamp spontaneously. The same
phenomena are produced by the vapour of camphor; and an aromatic
fumigating lamp has lately been advertised for sale, which is no
other than the contrivance above described; and it is evident
that, if the spirit be impregnated with fragrant principles, an
aromatic vinegar will be developed during its slow combustion,
and diffused in fumes through the apartment.

This experiment on the slow combustion of ether is accompanied with the formation of a peculiar acrid and volatile substance possessed of acid properties, which has been particularly examined by Mr. Daniell, who, having at first regarded it as a new acid, proposed for it the name of _Lampic_ acid, in allusion to the researches which led to its discovery; he has, however, since ascertained that its acidity is owing to the acetic acid, which is combined with some compound of carbon and hydrogen, different both from ether and alcohol.

The phenomena of slow combustion, as exhibited in certain states of the mine, by the Safety-lamp, are highly curious and interesting.

By suspending some coils of fine wire of platinum[37] above the wick of his lamp, the miner will be supplied with light in mixtures of fire-damp no longer explosive; for should his flame be extinguished by the quantity of fire-damp, the little coil of platinum will begin to glow with a light sufficiently bright to guide him in what would otherwise be impenetrable darkness, and to lead him into a purer atmosphere, when the heat thus increased will very frequently be sufficient to rekindle his lamp!

[37] Sir Humphry Davy attempted to produce the phenomena with
various other metals, but he only succeeded with platinum and
palladium; these bodies have low conducting powers, and small
capacities for heat, in comparison with other metals, which seem
to be the causes of their producing, continuing, and rendering
sensible, these slow combustions.

In this case it will be readily perceived, that the combustion of the fire-damp is continued so slowly, and at so low a temperature, as not to be adequate to that ignition of gaseous matter which constitutes flame, although it excites a temperature sufficient to render platinum wire luminous.

Sir Humphry Davy observes, that there never can be any danger with respect to respiration, whenever the wire continues ignited; for even this phenomenon ceases when the foul air forms about two-fifths of the volume of the atmosphere.

The experiment, as originally performed by the illustrious chemist, is so interesting and instructive, that I shall here relate it in his own words.

"I introduced into a wire-gauze Safe lamp a small cage made of fine wire of platinum of one-seventieth of an inch in thickness, and fixed it by means of a thick wire of the same metal about two inches above the wick which was lighted. I placed the whole apparatus in a large receiver, in which, by means of a gas-holder, the air could be contaminated to any extent with coal gas. As soon as there was a slight admixture of coal gas, the platinum became ignited; the ignition continued to increase till the flame of the wick was extinguished, and till the whole cylinder became filled with flame; it then diminished. When the quantity of coal gas was increased, so as to extinguish the flame, at the moment of the extinction the cage of platinum became white hot, and presented a most brilliant light. By increasing the quantity of the coal gas still farther, the ignition of the platinum became less vivid: when its light was barely sensible, small quantities of air were admitted, its heat speedily increased; and by regulating the admission of coal gas and air, it again became white hot, and soon after lighted the flame in the cylinder, which as usual, by the addition of more atmospherical air, rekindled the flame of the wick."

I have thus related, somewhat in detail, the history of a discovery, which, whether considered in relation to its scientific importance, or to its great practical value, must be regarded as one of the most splendid triumphs of human genius. It was the fruit of elaborate experiment and close induction; chance, or accident, which comes in for so large a share of the credit of human invention, has no claims to prefer upon this occasion; step by step, may he be followed throughout the whole progress of his research, and so obviously does the discovery of each new fact spring from those that preceded it, that we never for a moment lose sight of our philosopher, but keep pace with him during the whole of his curious enquiry.

He commenced, as we have seen, with ascertaining the degree of combustibility of the fire-damp, and the limits in which the proportions of atmospheric air and carburetted hydrogen can be combined, so as to afford an explosive mixture. He was then led to examine the effects of the admixture of azote and carbonic acid gas; and the result of those experiments furnished him with the basis of his first plan of security. His next step was to enquire whether explosions of gas would pass through tubes; and on finding that this did not happen, if the tubes were of certain lengths and diameters, he proceeded to examine the limits of such conditions, and by shortening the tubes, diminishing their diameters, and multiplying their number, he at length arrived at the conclusion, that a simple tissue of wire-gauze afforded all the means of perfect security; and he constructed a lamp, which has been truly declared to be as marvellous in its operation, as the storied lamp of Aladdin, realizing its fabled powers of conducting in safety, through "fiends of combustion," to the hidden treasures of the earth. We behold a power which, in its effects, seemed to emulate the violence of the volcano and the earthquake, at once restrained by an almost invisible and impalpable barrier of network--we behold, as it were, the dæmon of fire taken captive by Science, and ministering to the convenience of the miner, while harmlessly fluttering in an iron cage.

And yet, wonderful as the phenomenon may appear, his experiments and reasonings have demonstrated, that the interruption of flame by solid tissues permeable to light and air, depends upon no recondite or mysterious cause, but simply upon their cooling powers, which must always be proportional to the smallness of the mesh, and the mass of the metal.

When it is remembered that the security thus conferred upon the labouring community, is not merely the privilege of the age in which the discovery was effected, but must be extended to future times, and continue to preserve human life as long as coal is dug from our mines, can there be found in the whole compass of art or science, an invention more useful and glorious?

The wire-gauze lamp has now been several years extensively used in the mines, and the most satisfactory and unequivocal testimonies have been published of the complete security which it affords. They have amongst the miners obtained the name of _Davys_; and such is the confidence of the work men in their efficacy, that by their aid they enter the most explosive atmospheres, and explore the most remote caverns, without the least dread of their old enemy the _fire-damp_.

Into the mines of foreign countries the Safety-lamp has been introduced with similar success; and the illustrious discoverer has been repeatedly gratified by accounts of the enthusiasm with which his invention has been adopted in various parts of Europe.[38]

[38] A pamphlet appeared at Mons, in the year 1818, on the
explosions that occur in coal mines, and on the means of
preventing them by Davy's Safety-lamp. It was published under
the direction of the Chamber of Commerce and Manufactures of
Mons, accompanied by notes, and by the results of a series of
experiments that had been conducted by M. Gossart, President
of the Chamber. The province of Hainault is said to be richer
in coal mines than any other part of the Continent of Europe,
and to have no less than one hundred thousand persons employed
in the working them. The same kind of dangerous accidents
occurred in these mines as in those of the North of England,
and various expedients had been adopted for their prevention,
which, however, availed but little in obviating them. "All the
precautions," observe the reporters, "which had been hitherto
known or practised, had not been able to preserve the unfortunate
miners from the terrible effects of explosion. It is therefore an
inappreciable benefit which we confer by making known the equally
simple and infallible method of preventing these accidents, which
has been discovered by the celebrated Humphry Davy."

M. Gossart gives an ample and accurate detail of the properties
of the explosive gas, and confirms the truth of Davy's
experiments, by which the high temperature necessary for its
inflammation, and the consequent means of preventing it, by
reducing that temperature, as effected during its passage through
wire-gauze, are clearly demonstrated.

The lamp appears from this report to have been as useful in the
mines of Flanders as in those of England. The Pamphlet is a
valuable document, inasmuch as it affords an independent proof of
the security of the instrument, and displays the high sense of
obligation which foreign nations entertain to Sir Humphry Davy
for his invention.

Nor is the utility of this invention limited to the operations of mining. In gas manufactories, spirit warehouses,[39] or druggists' laboratories, and in various other situations, where the existence of an explosive atmosphere[40] may expose persons to danger, the Safety-lamp may be advantageously used; and as science proceeds in multiplying the resources of art, this instrument will no doubt be found capable of many new applications.

[39] The danger of carrying a naked light into an atmosphere
impregnated with the fumes of spirit was awfully exemplified
by the loss of the Kent East Indiaman, by fire, in the Bay of
Biscay, on the 1st of March 1825.

[40] In cases where there is any suspicion of accumulations of
carburetted hydrogen from the leakage of gas pipes, or from other
sources, the safety-lamp should always be employed. A terrible
accident occurred some years since at Woolwich, from a room
filled with the vapour of coal-tar, for the purpose of drying and
seasoning timber intended for ship-building. As the combustion
arose from the flame issuing through the flue, which ran along
the apartment, at the moment the damper was applied at the top
of the building, it is evident that, had a wire-gauze guard
been used, the accident could not have occurred. The house was
completely demolished, and nine persons were unfortunately killed.

By the permission of the President and Council of the Royal Society, several accounts of these researches, and of the invention and use of the Safety-lamp were printed, and circulated through the coal districts.

It might have been fairly expected that, in a district which had been so continually and so awfully visited by explosions, against which no human foresight had as yet been able to provide a remedy, the disinterested services of the greatest chemist of the age would at least have been received without a dissentient voice, and that his invention of security would have escaped the common fate of all great discoveries, and been accepted with every homage of respect and gratitude; but the inventor of the Safety-lamp was doomed to encounter a bitter hostility from persons whom a spirit of rivalry, or a feeling of hopeless emulation, had cemented into a faction.

From the period of the first announcement of the Safety-lamp, a prejudice against its use was industriously circulated amongst the miners; and some persons even maintained the monstrous proposition, that any protection against the explosions of fire-damp would injure more than it could serve the collier, by inducing him to resume abandoned works, and thus continually to inhale a noxious atmosphere.

The utility of the lamp having been established, in spite of every opposition, the claims of Sir H. Davy to its invention were next publicly challenged.

It will hereafter be scarcely believed that an invention so eminently philosophic, and which could never have been derived but from the sterling treasury of science, should have been claimed in behalf of an engine-wright of Killingworth, of the name of Stephenson--a person not even professing a knowledge of the elements of chemistry. As the controversy to which this claim gave birth has long since subsided, I would willingly have treated it as a passing cloud, had not its shadow remained. The circumstances, however, of the transaction stand recorded in the Magazines of the day, and the biographer of Davy would compromise his rights, by omitting to notice the attempts that have been made to invalidate them.

The claims which were made for the priority of Mr. Stephenson's invention of the Safety-lamp were urged in several communications in the Newcastle Courant. It has been said in reply, that if dates were taken as evidence, not merely of priority, but of originality of invention, it must follow that Mr. Stephenson's lamp was derived from that of Sir H. Davy. With regard to the first of Stephenson's lamps, the only one upon which the shadow even of a claim can be founded, it is unnecessary for the friends of truth to adopt such a line of defence; indeed, after a deliberate examination of all that has been published on the subject, I am very willing to believe that Mr. Stephenson did construct the lamp which dates its origin from the 21st of October 1815, without any previous knowledge of the conclusions at which Davy had arrived; for it was first announced to the Coal-trade by Mr. R. Lambert on the 3rd of November, to the very meeting at which Sir H. Davy's private letter was inadvertently read.--But what were the principles, and what the construction of this lamp?

It would appear that Mr. Stephenson had entertained some vague notion of the practicability of consuming the fire-damp as fast as it entered the lamp, and that if admitted only in small quantities, it would not explode the surrounding atmosphere: for effecting this object, he constructed a lamp with an orifice, over which was placed a slide, by the movement of which the opening could be enlarged, or diminished, and the volume of fire-damp to be admitted into the lamp regulated according to circumstances. Now such a lamp could be nothing else than an exploding lamp; for to make it burn in common air, the orifice must have been so wide that, on going into an explosive atmosphere, the combustion in the interior could not have failed to pass it, and to have exploded the mine. Here then is a _safety_-lamp, which as long as it is safe, will not burn, and the moment it begins to burn, it becomes unsafe!

The testimonies in favour of the security afforded by this lamp were evidently procured from persons who were not only ignorant of the principles of its construction, but of the methods to be pursued for ascertaining its safety. I am surely justified in such a statement, when, instead of an _explosive mixture_, I find them throwing in _pure fire-damp_, which will always extinguish flame, whether burning in a safe or unsafe lamp.

The importance and utility of Davy's lamp having been completely established by the severest ordeals, the general gratitude of the country began more publicly to display itself, and a very strong feeling prevailed, that some tribute of respect should be paid to its inventor; in accordance with which, a deputation of the Coal-owners of the rivers Tyne and Wear, and of the ports of Hartley and Blyth, requested the honour of an interview with Sir H. Davy; upon which occasion they presented him with the following letter, containing an expression of the thanks of the Coal-owners.

TO SIR HUMPHRY DAVY, LL.D. &c.

Newcastle, March 25, 1816.

SIR,

As chairman of the general meeting of proprietors of coal-mines
upon the rivers Tyne and Wear, held in the Assembly-rooms at
Newcastle, on the 18th instant, I was requested to express
to you their united thanks and approbation for the great and
important discovery of your Safety-lamp for exploring mines
charged with inflammable gas, which they consider admirably
calculated to obviate those dreadful calamities, and the
lamentable sacrifice of human life, which of late years have so
frequently occurred in the mines of this country.

They are most powerfully impressed with admiration and
gratitude towards the splendid talents and brilliant
acquirements that have achieved so momentous and important
a discovery, unparalleled in the history of mining, and not
surpassed by any discovery of the present age; and they hope
that, whilst the tribute of applause and glory is showered
down upon those who invent the weapons of destruction, this
great and unrivalled discovery for preserving the lives of our
fellow-creatures, will be rewarded by some mark of national
distinction and honour. I am, Sir,

Your most obedient humble Servant,
GEORGE WALDIE, Chairman.

A plan, however, was under consideration for recording the admiration and gratitude of the Coal-owners, by a more permanent and solid memorial. The nature of this proposition will be best disclosed by inserting the following letter from Mr. Buddle.

TO THE REV. DR. GRAY.

Wall's-End Colliery, August 27, 1816.

SIR,

As I know that you feel much interest in all matters relating
to Sir H. Davy's Safety-lamp, I trust you will excuse the
liberty I take in informing you, that the Committee of the
Tyne, approving highly of the suggestion, that some mark of
acknowledgment and respect should be presented to Sir Humphry
by the Coal-trade of this country, for the happy invention
of his lamp, have convened a general meeting of Coal-owners,
to be holden at my office in Newcastle, on Saturday next the
31st instant, at twelve o'clock, to take the subject into
consideration.

I should have sooner informed you of this proposed meeting,
had I not been detained in Cumberland until yesterday; but I
shall have the pleasure of transmitting to you a copy of its
resolutions.

I am sure that you will be gratified to learn that the lamps
continue to go on as well as possible. We now have twelve dozen
of them in daily use at this place. I have the pleasure to
remain, with the greatest respect, Sir,

Your most obedient humble Servant,
JOHN BUDDLE.

TO THE SAME.

Newcastle, September 7, 1816.

SIR,

I now have the pleasure of sending you a copy of the
Resolutions of the general meeting of Coal-owners on the 31st
instant, and shall take the liberty of informing you of the
future progress of this affair.

Sir Humphry did me the honour yesterday to accompany me
through the workings of a coal-pit at Wall's-End, when I had
an opportunity of witnessing several interesting experiments
on his Safety-lamp; and I have the satisfaction to add, that
I believe he has now advanced it to the highest degree of
perfection.

I am, respectfully, Sir,
Your humble Servant,
JOHN BUDDLE.

The satisfactory result of this visit Sir Humphry communicated to Mr. Lambton, now Lord Durham; and I shall take this opportunity to state, that for this as well as for several other letters I shall hereafter have occasion to introduce, I am indebted to that noble Lord, through the kind application of my friend Sir Cuthbert Sharp.

TO J. G. LAMBTON, ESQ. M.P.

Newcastle, September 9, 1816.

MY DEAR SIR,

Since I last had the pleasure of seeing you, I have examined
the workings in the Wall's-End collieries by the lamps, and
have tried them in various explosive mixtures.

On Sunday, I went with Mr. Buddle to your _blower_, with the
single lamps furnished with small tin reflectors. This simple
modification rendered them perfectly safe, even in the furious
_blow-pipe_, and at the same time increased their light.
Nothing could be more satisfactory than all the trials.

I have left a paper in the hands of the Rev. J. Hodgson, which
will be printed in a day or two; and I have desired him to send
you ten copies, or as many more as you may like to have.

I trust I have now left nothing undone as to the perfect
security of the lamps, under every possible circumstance.

I feel highly gratified that it was at your mines I effected
the only object that remained to be accomplished--that of
guarding against _blowers_ meeting fresh currents of air.

I thank you very sincerely for the interest you have taken in
the lamps, connected with my efforts to render them applicable
in all cases. I remain, &c.

H. DAVY.

On the 19th of October 1816, a letter appeared in the Durham County Advertiser, dated "Gosforth, August 22nd, 1816," in the name of Mr. W. Brandling, in which, alluding to the Resolutions of the Coal-owners of the 31st of August, he expresses a wish that a strict examination should take place previous to the adoption of a measure which might convey a decided opinion to the public, as to the person to whom the invaluable discovery of the Safety-lamp is actually due. "The conviction," says he, "upon my mind is, that Mr. George Stephenson, of Killingworth Colliery, is the person who first discovered and applied the principle upon which safe lamps may be constructed; for, whether the hydrogen gas is admitted through capillary tubes, or through the apertures of wire-gauze, which may be considered as merely the orifices of capillary tubes, does not, as I conceive, in the least affect the principle.

"In the communications I have seen from Sir H. Davy, no dates are mentioned; and it is by a reference to them only that the question can be fairly decided. For the information of the Meeting, therefore, I shall take the liberty of enclosing some which I received from Mr. Stephenson, to the correctness of which, as far as I am concerned, I can bear testimony; at the same time I beg leave to add, that the principle of admitting hydrogen gas in such small detached portions that it would be consumed by combustion,[41] was, I understand, stated by him to several gentlemen, as the idea he had embraced two months before his lamp was originally constructed."

[41] Granted:--but what connexion has that with the principle of
Davy's lamp, or with any _Safety_ lamp?

Mr. Brandling then proceeds to state, that the Killingworth lamp, with a tube to admit the air, and a slide at the bottom of such tube to regulate the quantity to be admitted, was first tried in the Killingworth pits on Saturday October the 21st, 1815; but not being found to burn well, another was ordered the same day with three capillary tubes to admit the air; and on being tried in the mine on the 4th of November following, was found to burn better and to be perfectly _safe_.[42] On the 17th of November, it was _tried_[43] at Killingworth office with inflammable air before Richard Lambert, Esq.; and on the 24th of the same month, before C. J. Brandling, Esq. and Mr. Murray.

[42] It could not have been safe.

[43] "Tried"--but how was it tried?--by forcing in _pure_
fire-damp, which will extinguish any lamp, instead of exposing
the flame to an explosive mixture, which could alone furnish any
test of its security.

"On the 30th of November," he says, "a lamp was tried in the mine, in which the air was admitted by means of a double row of small perforations, and found to be perfectly safe, and to burn extremely well."[44]

[44] Very likely: but the reader will please to recollect,
that Sir H. Davy had, before this, published an account of his
principle of safety by systems of tubes or canals.

At an adjourned Meeting of the Coal-owners, held on the 11th of October 1816, J. G. Lambton, Esq. M.P. in the chair; Mr. William Brandling moved--"That the meeting do adjourn, until, by a comparison of dates, it shall be ascertained whether the merit of the Safety-lamp belongs to Sir Humphry Davy or to Mr. George Stephenson."

On the question being put thereon, THE SAME PASSED IN THE NEGATIVE.

A great number of the Coal-owners, instead of pursuing the idea which had at first been suggested, of a general contribution on the vend, immediately commenced a subscription of individual proprietors of coal-mines; a measure which, it was thought, would express more distinctly and unequivocally the opinion of the trade as to the merit of the invention. The plan is developed in the following letter.

TO THE REVEREND DR. GRAY.

Wall's-End Colliery, October 27, 1816.

SIR,

It is the anxious wish of almost every individual in the trade
to compliment Sir Humphry Davy, in that way which may be most
grateful to his feelings.

It has been suggested that the object will be best attained by
substituting an individual (colliery) subscription, instead of
the proposed contribution on the vend; and it will at the same
time show more distinctly the real opinion of the trade as to
the merit of the invention.

This idea was not suggested till yesterday afternoon, and of
course there has been but little time to communicate it to
the several Coal-owners; but _all_ who have heard of the plan
approve of it.

To facilitate the business, the committee have formed the
annexed scale of contribution.[45]

* * * * *

I trust, Sir, you will excuse the trouble which I have given
you on this subject; but I am aware that you must feel
interested in it; and I hope, Sir, you will allow me to add,
that I am fully sensible of the obligation which the Coal trade
is under to yourself, for having drawn Sir H. Davy's attention
to that particular line of investigation, which has led to the
important discovery of the Safety-lamp. I am, Sir, with the
greatest respect, your most obedient humble servant,

JOHN BUDDLE.

[45] I have not thought it necessary to enumerate the various
sums which the different mines were called upon to contribute.

Some slight alterations were afterwards made in this scheme, in consequence of a wish having been expressed that the Bishop of Durham and the Duke of Northumberland should take the lead in a subscription. The following letter conveys some farther information upon this subject.

TO THE REVEREND DR. GRAY.

Newcastle, January 11, 1817.

SIR,

I have to acknowledge the receipt of your letter of the 9th
instant, communicating the intention of the Reverend the Dean
and Chapter of Durham, to subscribe fifty guineas towards the
plate to be presented to Sir H. Davy, which, together with two
hundred guineas from the Coal-owners of the Wear, makes the
subscription amount to nearly £1500, and I shall expect some
farther subscriptions.

I am sure it will afford you satisfaction to learn that the
lamps still continue to give the most gratifying proofs of
the advantages resulting from their invention, and that not a
single inch of human skin has been lost by fire, wherever they
have been used.

Sir Humphry has just made another important improvement in the
lamp, by constructing the cylinder of _twisted_ wire-gauze.
Lamps thus constructed, possess the singular property of not
becoming red-hot, under any circumstances of exposure to
explosive mixtures, whether urged by a blast, or in a state of
rest. I am with great respect, Sir, your most obedient humble
servant,

JOHN BUDDLE.

It may be collected from the following letter, that the Committee, in announcing to Sir H. Davy the intended present of plate, delicately sounded him as to the form in which it would be most agreeable to him.

TO N. CLAYTON, ESQ.

Grosvenor Street, March 23, 1817.

SIR,

On my return to town, after an absence of some days, I found
the letter of March the 13th, with which you honoured me, at
the Royal Institution. I shall not lose a moment in replying
to it, and in expressing my grateful feelings for the very
flattering communication it contains.

The gentlemen interested in the coal-mines of the two rivers
Tyne and Wear, cannot offer me any testimony of their kindness,
which I shall not receive with infinite pleasure.

I hardly know how to explain myself on the particular subject
of your letter; but as the Committee express themselves
satisfied as to the utility of the Safety-lamp, I can only
desire that their present, as it is highly honourable to me,
should be likewise useful to my friends, and a small social
circle, which it would be as a dinner-service for ten or twelve
persons.

I wish that even the plate from which I eat should awaken my
remembrance of their liberality, and put me in mind of an event
which marks one of the happiest periods of my life.

I cannot find any language sufficiently strong to express my
thanks to the gentlemen for the manner in which they have
distinguished my exertions in their cause, and in the cause of
humanity. I have the honour to remain, &c.

H. DAVY.

To revert once again to the faction--for such I must denominate it--which, in opposition to the most unequivocal evidence, continued to support the unjust claims of Mr. Stephenson; it would appear from various letters in my possession, that the feelings of Davy were greatly exasperated by this ungenerous conduct.

I shall introduce one of these letters, playful in the midst of its wrath, addressed to Mr. Lambton, the friend[46] of his youth, and the manly and kind supporter of his scientific character, in the hour of persecution.

[46] It will be remembered that they resided together in the
house of Dr. Beddoes. See page 59, vol. i. of these memoirs.
In the library at Lambton, there is a goodportrait of
Sir Humphry.

TO J. G. LAMBTON, ESQ. M.P.

Queen Square, Bath, Oct. 29, 1816.

MY DEAR SIR,

The severe indisposition of my wife has altered my plans. Your
letter slowly followed me here.

Mr. ---- is one of the persons who, after I had advanced a
principle of security for a lamp, came upon the ground to
endeavour to jockey me. I was not looking to a prize, I merely
came forward to show an animal, the breed of which might be
useful, when Mr.----, Dr.----, &c. brought their sorry jades,
which had never before been seen or heard of, to kick at my
blood mare.

I never heard a word of George Stephenson and his lamps till
six weeks after my principle of security had been published;
and the general impression of the scientific men in London,
which is confirmed by what I heard at Newcastle, is, that
Stephenson had some loose idea floating in his mind, which he
had unsuccessfully attempted to put in practice till after my
labours were made known;--then, he made something like a safe
lamp, except that it is not _safe_, for the apertures below are
four times, and those above, twenty times too large; but, even
if Stephenson's plans had not been posterior to my principles,
still there is no analogy between his glass exploding machine,
and my metallic tissue, permeable to light and air, and
impermeable to flame.

I am very glad that you attended the meeting; your conduct
at no very distant period will be contrasted with that of
some great coal-proprietors, who find reasons for their
indifference, as to a benefit conferred upon them, in
insinuations respecting the claims of Dr. Clanny, Mr.
Stephenson, and others.

Where men resolve to be ungrateful, it is natural that they
should be illiberal; and illiberality often hardens into
malignity.

I shall receive any present of plate under your auspices, and
those of the Committee over which you preside, with peculiar
satisfaction. It will prove to me that my labours have not been
disregarded by men of whose good opinion I am proud.

I hope you will not blame me for not taking any notice of the
attacks of my enemies in the North. I have no desire to go out
of my way to crush gnats that buzz at a distance, and do not
bite me, or to quarrel with persons who shoot arrows at the
moon, and believe, because they have for an instant intercepted
a portion of her light, that they have hit their mark. I am
sensible to the circumstances under which you attended the
meeting.

I offer you my sincere congratulations, and ardent wishes that
you may enjoy all possible happiness.

Believe me, &c.

H. Davy.

On the 13th of September 1817, Sir Humphry Davy being expected to pass through Newcastle on his return from Scotland, preparations were made, and notice given of a dinner which it was proposed should take place on the 25th instant, for the purpose of presenting to the illustrious philosopher the service of plate which had been prepared for his acceptance.

Upon this gratifying occasion, a very large party assembled at the Queen's Head, consisting of a numerous and respectable body of Coal-owners, and such other gentlemen as had interested themselves during the progress of the investigation, or taken an active part in promoting the introduction of the lamp into the mines.

After the dinner had concluded, and certain toasts of form had been drunk, Mr. Lambton, who filled the chair on the occasion, rose, and on presenting the service of plate to the illustrious guest, addressed him, in a tone of great animation and feeling, in nearly the following terms:

"SIR HUMPHRY,--It now becomes my duty to fulfill the object of the meeting, in presenting to you this service of plate, from the Coal-owners of the Tyne and Wear, as a testimony of their gratitude for the services you have rendered to them and to humanity.

"Your brilliant genius, which has been so long employed in an unparalleled manner, in extending the boundaries of chemical knowledge, never accomplished a higher object, nor obtained a nobler triumph.

"You had to contend with an element of destruction which seemed uncontrollable by human power; which not only rendered the property of the coal-owner insecure, but kept him in perpetual alarm for the safety of the intrepid miner in his service, and often exhibited to him the most appalling scenes of death, and heart-sickening misery.

"You have increased the value of an important branch of productive industry; and, what is of infinitely greater importance, you have contributed to the lives and persons of multitudes of your fellow-creatures.

"It is now nearly two years that your Safety-lamp has been used by hundreds of miners in the most dangerous recesses of the earth, and under the most trying circumstances. Not a single failure has occurred--its absolute security is demonstrated. I have, indeed, deeply to lament more than one catastrophe, produced by fool-hardiness and ignorance, in neglecting to use the safeguard you have supplied; but these dreadful accidents even, if possible, exalt its importance.

"If your fame had needed any thing to make it immortal, this discovery alone would have carried it down to future ages, and connected it with benefits and blessings.

"Receive, Sir Humphry, this permanent memorial of our profound respect and high admiration--a testimony, we trust, equally honourable to you and to us. We hope you will have as much pleasure in receiving, as we feel in offering it. Long may you live to use it--long may you live to pursue your splendid career of scientific discovery, and to give new claims to the gratitude and praise of the world!" Sir Humphry having received the plate, replied as follows:

"GENTLEMEN,--I feel it impossible to reply, in an appropriate manner, to the very eloquent and flattering address of your distinguished Chairman. Eloquence, or even accuracy of language, is incompatible with strong feeling; and on an occasion like the present, you will give me credit for no small degree of emotion.

"I have been informed that my labours have been useful to an important branch of human industry connected with our arts, our manufactures, commerce, and national wealth. To learn this from such practical authority is the highest gratification to a person whose ardent desire has always been to apply science to purposes of utility.

"It has been also stated, that the invention which you are this day so highly honouring, has been subservient to the preservation of the lives and persons of a most useful and laborious class of men: this, coming from your own knowledge, founded upon such ample experience, affords me a pleasure still more exalted--for the highest ambition of my life has been to deserve the name of a friend to humanity.

"To crown all, you have, as it were, embodied these sentiments in a permanent and magnificent memorial of your good opinion. I can make only imperfect and inadequate efforts to thank you.

"Under all circumstances of my future life, the recollection of this day will warm my heart; and this noble expression of your kindness will awaken my gratitude to the latest moment of my existence."

Sir Humphry having sat down, and the cheering of the company subsided, the Chairman proposed the health of the illustrious Chemist, in three times three.

"Gentlemen," said Sir Humphry, "I am overpowered by these reiterated proofs of your approbation. You have overrated my merits. My success in your cause must be attributed to my having followed the path of experiment and induction discovered by philosophers who have preceded me: willingly would I divide your plaudits with other men of science, and claim much for the general glory of scientific discovery in a long course of ages.

"Gentlemen, I might dwell at some length upon the great increase of wealth and power to the country, within the last half century, by scientific invention, which never could have existed without coal-mines:--I shall refer only to the improvement in the potteries, to the steam-engine, and to the discovery of the gas lights.

"What an immense impulse has the steam-engine given to the arts and manufactures! How much has it diminished labour, and increased the real strength of the country, far beyond a mere increase of population! By giving facilities to a number of other inventions, it has produced even a moral effect in rendering capital necessary for the perfection of labour, credit essential to capital, and ingenuity and mental energy a secure and dignified species of property.

"Science, Gentlemen, is of infinitely more importance to a state than may at first sight appear possible; for no source of wealth and power can be entirely independent of it; and no class of men are so well able to appreciate its advantages as that to which I am now addressing myself. You have not only derived from it the means of raising your subterraneous wealth, but those also of rendering it available to the public.

"Science alone has made pit-coal such an instrument in the hands of the chemist and mechanic; it has made the elements of fire and water perform operations which formerly demanded human labour, and it has converted the productions of the earth into a thousand new forms of use and beauty.