because we have the appliances for the manufacture of this gas at our command. It was not my intention, in the paper I prepared, to make any statements in regard to the scientific analysis of the gas, the results of photometric observations, or any thing of that kind; but merely to give practical results.

MR. EDGERTON-I did not happen to be here yesterday when the paper was read by Mr. Chambers. understood there would be no further discussion of naphtha In fact, I had gas, and for that reason it was not my intention to attend the meetings of the Association; but, hearing that a paper had been read, stating results that were unfavorable to that process of making gas, I determined to enter into the discussion, and give a few facts. The points I desire to make in regard to naphtha gas, are confined to facts and results entirely outside of the works. I do not wish, with but one exception, to make the slightest reference to any information to be obtained inside the gas works. What I have to say about the cost of the production of naphtha gas, can be demonstrated by that which can be learned outside the works; and the reason, I briefly state, is this-that if oil is passed through a red-hot retort, it is decomposed into two classes of gas-illuminating gas, and non-illuminating gas. I have found by numerous tests, that the percentage of illuminating gas is a fair indication, in fact, a more exact indication than can be had in any other manner, of the amount of oil used. Upon this basis I have made, since I have been in the city, quite a number of observations of the methods of making gas here from oil, and I will give you the result.

In the first place, I have made examinations and inquiries concerning the composition of a gas known as the "Tessie du Motay gas.' I do not know why that name is given it, but it is manufactured at the works of the Municipal Gas Company. I found this gas contained 14.42 per cent. of illuminating gas, and of carbonic oxide 28 per cent. These figures, if proven,

will be a pretty fair estimate of the value. water gas assured me that the carbonic oxide was in the proPrevious tests with portion of 39.9 per cent. From that I considered the ratio of water gas to oil gas to be that of 28 to 39.9, and the balance of the gas to be the result of naphtha decomposition. Carrying these

figures out, I found the composition of the gas, as delivered to the consumer, was 70.2 per cent. of water gas, and 29.8 per cent. of naphtha gases. For the reasons given, the source of these two gases cannot be any other than that stated, viz., that the 70.2 per cent. must be the result of the decomposition of water, and the 29.8 per cent. must result from the decomposition of oil. Of this 29.8, the illuminating gases must necessarily be a part. They cannot come from water gas, for we know that it has no illuminating power whatever. Deducting the illuminant, 14.42 per cent., as above stated, from the total of the naphtha gases, 29.8 per cent., it leaves the non-illuminating product of naphtha decomposition 15.4 per cent.

Numerous tests and experiments have shown the total product from the decomposition of a gallon of naphtha to be from 70 to 80 cubic feet of gas.

As the proportion of naphtha gas found in Municipal gas was 29.8 per cent. of the whole, it follows that one thousand cubic feet of such gas consists of 298 cubic feet of naphtha gas, and the balance, 702 cubic feet, of water gas. The naphtha gas portion being yielded at the rate of 70 to 80 cubic feet per gallon, it would require from four to four and one-half gallons of naphtha per thousand. This gives, in my opinion, a basis to calculate upon, independent of any information derived at the works.

Now, the value of the gas is of the greatest importance because, in estimating the value of any product, it must be based upon the illuminating value of that product. On this point there is great difference of opinion. Most of the results and tests of naphtha gas in this country have been from Argand burners; but that is not a true test of rich gas. It is so tested in London by the Gas Referees. The system of testing in vogue here is not a true one, as I can show you.

I found the illuminating value of the Municipal gas, as tested with a flat flame burner, set at an angle of forty-five degrees with the bar, to be as follows:

2

Illuminating Power Meter, 22.750.

NEW YORK GAS COMPANY'S GAS, September 28th, 3 to 5 P. M. 5 foot excavated Lava Tip Bat's wing. Test made at 2 miles distance from works. (1)

The same gas, by Illuminating Power Meter, gave (1st series) mean of three tests, 23.160: Second series, three tests, 23.100.

3

Illuminating Power Meter, at beginning, 23.62: Illuminating Power Meter, at end, 24.75.

4

Illuminating Power Meter, 17.83.

SUGG ARGAND, "G." BURNER.-Gas rate, 4.95; Candle rate, grains, 120.6; Observed candle power, 22.860; Reduced candle power, 23.210. NEW YORK EXAMINER'S BURNER AND METHOD OF OBSERVING.-18 C. Sugg-Letheby, Sept. 28th, 1878.-Gas rate, 4.31; Candle rate, grains, 119.7; Observed candle power, 15,96; Reduced candle power, 18-47.

It will thus be seen that the indications of the illuminating power meter are higher than the fishtail and bat's wing on poor gas, and lower with rich gas. This is also the view of Mr. Sugg, only he does not state the amount of difference.

MR. C. WHITE-Was the gas tested with an argand burner, or with a common burner?

MR. EDGERTON-It was tested with a flat flame burner.

MR. C. WHITE-Were both gases tested with the same burner?

MR. EDGERTON-Both kinds were tested with the same burner.

But by the method of testing in vogue in New York I find that the same gas of the Municipal Company would be stated at 18.47 candles; so then, it will be observed, the commercial value of the gas is stated to be nearly nine candles less for five cubic feet. This arises from the fact that the method in vogue for testing is without precedent. It is not used anywhere in the world except in New York.

Mr. Farmer has conceived a very good means of making comparisons readily—that is, as stated in candle feet—the amount of the product and the actual value of the product.

I will here state that I have been requested not to bring up this subject of Municipal gas. I shall, of course, discuss it so far as I shall deem it proper. I shall state nothing that I do not find outside the works. I do not come here to state what

I find inside the works. I suppose the subject of naphtha and water gases is now under discussion, and whatever may be of use to the Association in that connection I consider myself at liberty to state. As I have said, the tests were all made with a flat flame burner, set at an angle of forty-five degrees with the bar. I consider that to be the fair way.

The London Gas Referees have adopted a method of using a flat flame to the disc. That magnifies the quality of rich gases slightly, and is not, therefore, the proper way. Hence, in considering this question of naphtha gas, you must take into consideration the fact that the commercial value of the product, as we find it, is double that of coal gases. I think that can be demonstrated beyond question.

MR. WHITE-At what price is the gas sold in this city?

MR. EDGERTON-I think they all charge a uniform rate for the gas per thousand. I have been informed that it was $2 25; but I have never paid a gas bill, and cannot speak from positive knowledge. I have heard the rate stated at $2.50 and $2.25. I believe that is all I have to say in regard to the ques-. tion.

MR. HELME—To ordinary mortals this question of naphtha and petroleum gas is a very perplexing one. It has occupied the attention of this Association, more or less, at every meeting for several years. We have heard the statement of Mr. Pear

son.

It was very straightforward, and looked as if it were honestly and fairly made; and I have no doubt he believes it. Every part of it may be true for aught I know; but there is one thing I would like to say, by way of reply, to some of the matters he has spoken of. He tells us he has been dealing with S. A. Stevens & Co., and speaks of the contract he has made with them.

MR. NEAL-Will the gentleman please suspend his remarks for a moment?

THE PRESIDENT-I have the honor of introducing to you, gentlemen, Mr. W. W. Greenough, of Boston, who has been elected an honorary member of this Association.

In the name of this Association, sir, I greet you with a hearty welcome.

MR. GREENOUGH-Gentlemen of the Association : : I have but one word to say, and that is, that I am very greatly obliged for the honor you have conferred upon me in electing me an honorary member of this Association. [Applause.]

MR. HELME-Mr. Pearson stated that S. A. Stevens & Co. have made a proposition to him, which he thinks is satisfactory, and it does look to be exceedingly fair; but in the city of Philadelphia, where S. A. Stevens & Co. live, where they have started their business, and have carried it on to the present time, they had an apparatus in operation, with purifiers and station meters, and everything that they have about gas works, and everything they could desire to make their enterprise a