The roll call for the year shows as follows:

Deceased Members.-James D. Brewer, of Springfield, Mass., and John Anderson, of Ironton, Ohio.

On motion of Mr. Nettleton the report was received and ordered to be spread upon the minutes.

REPORT OF FINANCE COMMITTEE.

PHILADELPHIA, PA., Oct. 19, 1886.

To the Members of the American Gas Light Association :— Gentlemen: Your Finance Committee would respectfully report that they have examined the books and accounts of the Treasurer and Secretary, C. J. R. Humphreys, for the year ending Sept. 30, 1886, and find the same to be correct.

On motion of Capt. White the report was received and ordered to be spread upon the minutes.

NOMINATING COMMITTEE.

On motion of Mr. Stedman a committee of five was appointed by the President to prepare a list of nominations for officers for

the ensuing year. The President appointed the following persons as such committee:-Messrs. W. A. Stedman, G. G. Ramsdell, F. W. Gates, A. E. Boardman, and J. R. Thomas. The committee was instructed to report back after first recess.

PLACE FOR HOLDING NEXT ANNUAL MEETING.

On motion of Capt. White, a committee of five was appointed to name a place for holding the next annual meeting. The President named the following members as such committee: Messrs. W. H. White, W. C. Butterworth, John McDougall, John Andrew, and Marcus Smith.

GAS APPLIANCES EXHIBITION.

Mr. Nettleton moved that the President appoint a special committee to take charge of the matter of a proposed exhibition of gas appliances, the committee to be named any time after the place for holding the next annual meeting had been settled upon. Agreed to.

Mr. R. B. Taber, of New Bedford, Mass., then read the following paper on

CONDENSATION.

When Citizen Napoleon Bonaparte as First Consul had been installed in the Palace of the Bourbons, after the completion of the ceremonies, turning to his secretary he said: "Sir, we are now here; the difficulty is to remain."

. In your audience hall to-day I, too, recognize the need of a plebiscite of your good will in the consideration of an old subject, but an extremely interesting one-the control and curbing of the immensely powerful energies developed in the distillation. And if I tread hastily on rudimentary ground unworthy of your time, I hope to atone for my error by provoking a discussion which shall make possible the next step after regenerative distillation— a true method of fractional condensation.

The condensation of gas, as understood generally, has for its object the cooling of the gas, the deposit of volatile matters, and the elimination of such hydrocarbons as are noxious to the illuminating power. The development process is over, the distillation of the coal has proceeded with its intense heat, however

imperfectly, and now from this mass there must be saved whatever is of value in the reduction of temperature.

The problem is difficult and extremely complex, since it combines mechanical and chemical energy, and has to deal with gases of intense energy. Of the 29 per cent. of the products of the ton of coal rendered volatile or gaseous 15 per cent. are gases -13 in number; the balance, numbering nearly 40 more, with boiling points varying from 17° C. to 370° C., differing inter se in vapor, density, and latent heat, all the while possessing a strong chemical affinity for each other. If, now, we add to this mass constant changes in volume, varying every minute in the lifetime of the charge, varying velocity at varying temperatures-here always a means of motion "--we have a conception of the state of " fierce unrest " developed in the mouthpiece. And from this is to be deposited, deprived of its heat and noxious elements, an inert gas in the gasholders, as far as practicable made proof against all future changes. For all this the time allowed is less than two minutes; and this is condensation.

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In this hurry one almost detects a trace of sarcasm in the bylaw propounded that all condensation should take place slowly and successively, and never violently. We will take the law for what it means, however, relatively if not absolutely, and detect the apparent adaptation of it in the gasholder used with a diaphragm, as at the South Metropolitan works of London, and the various ideas of hot condensers in this country.

This law is founded upon the double nature of the process of condensation—the chemical one of the deprivation of heat, and the mechanical one of the deposition of suspended matter-both interwoven, since the gases are saturated chemically, at the same time brushing away in the velocity of the current little globules of imperfectly distilled matter, to be deposited later on as occasion serves. And this chemical condensation is to cool and conserve; for the expression of M. Servier, in his foot-note to Herr Schilling's book on Gas Management, " Condenser n'est pas refroidir," adds, "This principle of conservation of the illuminating benzine, which contains 65 per cent. of the total lighting power, develops the second law-viz., elimination of all heavy tars while hot from the gas, allowing a contact for only such a period as shall allow all the benzines to be separated."

If we knew, then, more of the nature of the atoms of the mass and their subsequent behavior, the temperature and time of contact might be definitely determined. The experiment has been tried both in this country and abroad, in what was recorded as one of the successes of the year 1881, in the annual editorial review of the Journal of Gas Lighting. To-day this subject lies in a state of "innocuous desuetude," and most of the published reports are afraid to say whether it increased the candle power or not, and whether naphthaline was removed or not. Few attempts were recorded at that time giving strict thermometric readings, and although Young in the shale and Greville in the laboratory, with many French writers, were unanimous in the theoretic advantage, there had been no resuscitation of the subject until the prize dissertation of M. Guéguen, and the report of the Committee of the City of Paris, 1885, on what might be considered a progress in the manufacture of gas, bring to light further attempts in this direction.

But the fact remains, from the figures furnished in the 1885 report to the Paris Gas Company, that a normal coal distills, to the 100 kilos., 40 grammes of benzole-representing 7 per cent. of its weight and I per cent. of its volume. In an interesting article, by M. Greville, on the available amount of light naphtha which the gas has at its disposal, he would add from the stock tars one candle power, and agrees generally with other writers that one-third to one-quarter of the candle power is lost by imperfect condensation, through the chemical affinity of light and heavy tars. Another fact, extremely interesting, since it throws light on what may yet open a terra incognita, is the varying amount of benzine formed in different parts of the charge, increasing over 10 per cent. in the last third of its life—an increase which I fear is mostly lost in the cooler stand-pipe and cold hydraulic main, especially such as are quoted as sometimes standing at 45° C. or lower.

Turning hastily, now, for a moment to the question of temperature, I am surprised at its extreme velocity of operation. A single trial of the temperature of the stand-pipe, taken at short intervals during the burning off of a charge in the New Bedford works, showed a range of fall of 210° C. (376° F.) in the single charge, or 270° C. (486° F.) between its maximum and that of

the hydraulic main not 12 feet distant.* It were quite worthy of special study, this first beginning of condensation; the gas issuing, say, at from 400° to 500° C. from the retorts, and falling immediately in the mouthpiece and stand-pipe, variously depositing its distillate and redistilling—a sort of irregular fractional distillation going on in a 6-inch stand-pipe. In fact it is here that M. Greville has suggested such enlargement of the standpipe that the free hydrogen may have time to seize upon the carbons at their high heats and form illuminating products-a theory never put in practice, as far as I know. M. Greville says: "By the employment of large vessels in which the reduced velocity of the gas would allow time for the heavy particles of tar to settle, and by subsequent use of some system of straining, the tar will be separated at the same time that the temperature will be high, to permit the almost complete retention. of light."

This heat maximum, too, in the stand-pipe precedes both the maximum candle power and the maximum yield of gas, seemingly independent of both, since the loss of heat is thence constant to the end of the charge. The loss of temperature of the standpipe was evident on cleaning it, since it was found that the pitch at top and bottom was of very different character, melting above 150° C. near the mouthpiece; at the middle of the pipe at 100° C.; and at the top at 45° C.-clearly showing the different extent of the distillation.

In the hydraulic main, while the temperature responds feebly to that of the stand-pipe—say, varying 4 per cent. in the chargeit appears to be influenced wholly by the heat of the stack, being

*The following is the record of the experiment, August 30, 1886: Commencing at the middle of the charge, at 1:30 P.M, the following temperatures were noted on a thermometer with bulb inserted in stand-pipe: