apathy upon the needs of the consumers—so long was their career marked by difficulties and embarrassments. No sooner, however, were the claims of the consumers recognized, and efforts put forth to further their interests, than the prospects of the concern brightened; and by adhering to, and extending the same line of action, the goal of commercial prosperity was eventually reached.

Seeing, therefore, that the subject is of so supreme importance to consumers of gas, and that the interests of the consumer are closely interwoven with those of the manufacturer, it is eminently desirable that there should be more generally diffused a correct knowledge of the principles of economical gas consumption, and of the extent to which these principles are applied in the various burners which, from time to time, have been invented. No further apology ought therefore to be required in presenting to the reader the following disquisition on gas-burners. It may, however, be of advantage for me to state in brief, at the commencement, what are the objects I have in view, and what the chief considerations which have led me to write this treatise.

I purpose, then, to tell of the progress that has been made in apparatus for the development of light from coal gas; to relate how the crude and imperfect devices of the early inventors have been gradually improved upon; and, while not ignoring the drawbacks connected with recently invented burners, or the defects inherent to their construction, to show, in the superior achievements of these burners, how great an advance has been made upon the apparatus formerly in use. It will be, also, my endeavour to make plain the little understood phenomenon of the production of light by the combustion of coal gas; and to show the extent to which the illuminating power developed is dependent upon the burner employed. That there is need for such information as I propose to furnish must be sufficiently obvious to any one who has considered the waste of gas which takes place through Waste of gas. ignorance of the laws of its combustion, and through the use of defective burners. In a report presented to the Board of Trade by the London Gas Referees in 1871, it was stated that a number of burners had been tested, taken from various places of business in the Metropolis; the major portion of which gave out only one-half, and some of them not more than one-fourth, of the illuminating power capable of being developed from the gas. Although, since the time that report was penned, considerable progress has been made in the construction of burners, and in the more general adoption of efficient burners by the public, much yet remains to be done. Doubtless it would still be within the mark to assert that fully one-fifth of the gas consumed by the public might be saved by the adoption of better burners, and by the observance of the conditions necessary for their satisfactory operation; and when it is borne in mind that the gas-rental of the United Kingdom amounts to a sum of certainly not less than £9,000,000 per annum, the saving which might be effected assumes truly great proportions.

The field on which I propose to enter can hardly be said to be already occupied. Nowhere that I know of is the subject of gas-burners fully treated of in a manner available for the general reader. With the exception of the admirable chapter contributed by Mr. R. H. Patterson to "King's Treatise on Coal Gas," I am not aware that the subject has been dealt with to any complete extent by recent writers. But, admirable as is that contribution to the literature of the subject, being written for technical readers, it is neither so popular in style nor so elementary in character as to fulfil the purpose which I have in view in writing the present series of articles. Briefly stated, my sole purpose is to make the subject of the combustion of gas for the production of light intelligible to the simplest; and to present an interesting account of the progress of invention in the perfection of gas-burners. While passing lightly over many modifications of apparatus which have been of but limited or temporary service, I shall not scruple to dwell at length upon such burners as have done much to further the extension of gas lighting, or whose construction exhibits a considerable advance upon previous attainments. And while it will be my endeavour to clothe my remarks in such language as shall be "understanded of the people," in speaking of the theory of combustion I hope to be sufficiently explicit to enable my readers to form a clear conception of the scientific principles underlying the phenomena of which I treat.

A further justification—if such, indeed, were needed—for the Progress of gas lighting. appearance of this treatise might be found in the remarkable impetus which has been given, within recent years, to the perfection of the details of gas manufacture and the improvement of gas-burners. Of course, I refer to the beneficial consequences to the gas industry which have followed the brief, if conspicuous, career of electricity as an illuminating agent. That the interest in improved illumination which has been aroused by the short-lived popularity of the electric light, and the extravagant claims put forward on its behalf, have stimulated to the development of the resources of gas lighting, is sufficiently obvious to the most superficial observer. And not only has the manufacturer of gas been benefited, but the public have reaped no inconsiderable advantage. At the present day, gas is sold at a far cheaper rate, as well as of a higher quality, than at any former period. Nor is the advent of cheap gas the only direction in which the public have gained. Although not so patent to the majority, the improvements that have been effected in the methods of burning gas, so as to obtain the fullest advantage from its use, are calculated to confer benefits equally real, and not less valuable. It is hardly too much to say that the last few years have witnessed a greater advance in the apparatus employed in the combustion of gas than had been effected during the whole previous history of gas lighting. This being so, it may not be unacceptable if I attempt to pass in review some of the various burners that have been invented and used for obtaining light from coal gas; showing the successive improvements that are exhibited in their construction, and the extent to which they apply the principles of combustion. It may be that what I have to relate will awaken some minds to the consciousness that gas lighting has not altogether retired into obscurity on the advent of electricity—nay, that it has even assumed a bolder front; and, with increased resources and accession of strength, is prepared firmly to maintain its position as at once the most convenient, economical, and reliable of artificial illuminants.

CHAPTER II.

THE FIRST GAS-BURNER.

The first gas-burner was a very simple and unpretentious contrivance. In one of the earliest works on gas lighting[1] we read: "The extremities of the pipes have small apertures, out of which the gas issues; and the streams of gas, being lighted at those apertures, burn with a clear and steady flame as long as the supply of gas continues." Familiar as it is to us, and from its familiarity unnoticed, the phenomenon presented by the flame thus produced continuing to burn "as long as the supply of gas continued," was doubtless, to the first experimenters, a wonderful sight. Though we may smile at the question, it is not difficult to understand the incredulity of the honourable member who, when Murdock was examined before a Committee of the House of