while open furnace annealing (the usual practice) makes more scale which gradually rusts loose. The life of the holder shells may be greatly increased by careful attention to painting the exterior. Paints mixed with linseed oil are not desirable, because linseed oil is very porous and readily absorbs water. In specifying the allowable working strains in parts of the holder it will be best to provide that the bursting strain in the crown and the compression in the top curb of the inner section shall not exceed 12,000 pounds per square inch of the net section of metal, and that the shearing strains on the rivets involved shall not exceed 7,500 pounds per square inch.

In the guide frame of the gasholder particular attention should be given in arranging the various members so that all parts will be accessible for cleaning and painting. Connections between members involving rivets in tension should be avoided. In specifying the load for which the frame shall be designed it is better to express the amount in pounds per square foot of diametrical section of the holder at its full height rather than in a gale of a certain velocity in miles per hour, as the former method leaves no possible question as to the load.

DISCUSSION.

MR. SHELTON-I think there is no paper that will be of more practical value than this paper by Mr. Carpenter, if it leads to a good discussion of the points that the average gas man should look out for, in the construction of a gasholder. I speak from my own experience, and my own ignorance. I know very much less about the points that go to make up the right design, the right weights. and the right details of a gasholder than I should, or than I wish I did. I think I can go further and say that gas superintendents on this side of the Atlantic, as a class, are less practically informed as to the proper details of holder work than they should be. They know more about these things in England than we do, and I think it would be a great step in the right direction were this Association to take some action leading to more knowledge of gasholder design or towards establishing a standard of gasholder construction; certainly, in many fundamental details, it would benefit the members, because some or most of us have to buy gasholders more or less blindly.

MR. EGNER-I would like to say that the German Association of Gas and Water Engineers, of whom you know, some two years ago appointed a committee with the object that you suggest, that of drawing up gasholder standards. I think the remarks of Mr.

Shelton are well worthy of attention on that subject, and, if acted upon, will lead to such action as the German Association has taken in the matter.

MR. DOTY-I would like to ask Mr. Carpenter what difference in gauge he would recommend, with reference to the sizes and thicknesses of the plate, in the crown and side? If he would recommend 10 gauge for the side, would he recommend a heavier or lighter gauge for the crown?

THE PRESIDENT--Mr. Carpenter will answer all those questions collectively at the last.

MR. NORRIS-There is one practical point in regard to taking specifications just as they come from the makers of gasholders which I recently ran across. Where the makers of gasholders are asked to bid on a holder of a certain capacity, and no further specifications are given, there is a natural tendency on the part of the manufacturers to make the holder as light as is consistent with safety, in order to make the bid as low as possible. There is a marked tendency in modern gas practice to carry higher pressures on main systems, and where an endeavor is made to lighten up the holder to make it cheaper, we find very frequently that the inner section of such a holder is so light that it will not give us the maximum pressure which we wish to carry on our street mains; therefore, in asking for bids on holders, care should be taken to specify the pressure which we desire the holder to throw when uncupped. I have in mind the case of a holder that was being built for a gas company that we recently acquired. This holder, when uncupped, throws only 25-tenths, and the local conditions are such that we should have an available initial pressure of 40-tenths for supplying certain outlying districts; we are consequently obliged to use a fan booster when the holder uncups.

THE PRESIDENT-Mr. McIlhenny, you have bought one or two gasholders in your time. What is your experience with them?

MR. JOHN D. McILHENNY—The last one I had anything to do with was about 3 years ago, when we bought a steel tank holder of 75,000 cubic feet capacity. We simply accepted the specifications of a reliable holder maker, and never had any trouble. We had neither the time nor the knowledge to dictate how it should be built. We simply took the precaution to have 8 columns placed on the outside, instead of the usual number of 6, which was to give it greater wind-resisting power. That's all the suggestion we made about it.

MR. EGNER-Excuse me for rising again. I want to mention a little experience of my own. Once upon a time I was making a

trial at building gas works, and I gave it up after a year. During that time I was invited to bid on the construction of, I think, a 250,000 cubic foot gasholder. I made the drawings and specifications carefully and submitted my bid. I found out afterward from the superintendent of the company, and also from the President, that my bid was the lowest; I was led to believe that all would be asked to bid on the same kind of material in that holder, to make it give a certain pressure; but after my bid was in, and while I was feeling impressed with the idea that I was going to get the job very likely, a firm (whom I shall not name at all, of course) who were higher in their bid than I was, asked to have another chance at it. They did get another chance, and they then made a bid about $1200 lower than mine. I was then asked to revise my bid, but I didn't consider that I could make it any lower and give a good job, and so the construction company got the work. After that they were obliged to put in the weight of iron that I had calculated on, and they raised their price about $1800, thus making it higher than my bid. Now, if there were any standard for gasholders, as is proposed here to-day, this thing could never have happened. It would be better for the gas companies and the contractors to have a standard. I think the contractors would benefit more than the gas companies if there were standard holders for different sizes, giving different weights.

THE CHAIR-Mr. Goodnow, have you any suggestions to make looking to the taking of steps to secure standard specifications? MR. GOODNOW-I have had occasion in the last two or three years to go over several holder specifications, and I think this suggestion is a most excellent one. There are probably many others who don't know any more about such things than I do, and as the only means I had of determining these points was by comparison between the different holder makers, perhaps not a very intelligent deduction was made by comparisons of different specifications for the same thing. I also had occasion this year to compare bids for holders of practically the same size with bids that had been submitted a year or two ago, and found, from the same makers, a substantial difference in the specifications for the same holder, apparently. I don't mean in price, but in thickness of plates, angle irons, guide frames, etc. Now, a standard to go by would have been of great assistance to me, and I have no doubt to many others, and when the time comes to make a motion to that effect, I would like to move that a committee be appointed to devise some standard of measurements, especially for the smaller and medium-sized holders.

MR. COWDERY---I second Mr. Goodnow's motion that a committee be appointed by the Chair to do what can be done toward securing standard holder specifications, and to report to our next meeting the progress made during the year. I would also like to suggest in that connection that Mr. Baehr, superintendent of the works at Denver, is one of the best men in our Association to work up a matter of that kind.

(The motion was put and carried.)

THE PRESIDENT-The Chair is glad to have that motion made, and feels that the appointment of such committee will lead to practical results. They need not go into the last details of the matter, but if they can only lay down fundamental specifications at that we would be far ahead of where we are now. The Chair will appoint the committee before the adjournment of the convention.

MR. CARPENTER-Mr. Egner's remarks and the question of the smaller mills being able to manufacture large plates of a suitable quality for the sides of steel tanks are extremely important points. Many times a small mill might accept an order for a bill of material in which the weight of the largest plates would run very close to the largest ingot that the mill could cast, and probably the top portion of that ingot would come in the end of your plate. At the very point where you should have the best of material you would get the poorest. The test specimens cut from the side of such a plate might show satisfactory results. This is why I say that test specimens, even though cut from every plate, may be entirely worthless. You should look further than test specimens if you would be sure of the material in large plates. As to what kind of paint to use, I have no idea of a compromise in the price of the paint. I do not believe it makes any difference if you pay 2 or 3 dollars a gallon, as long as you get something that will adhere to the steel plate and not flake off, as well as a paint that will stand working in water. Now red lead, or any paint mixed with linseed oil, will not fulfill the latter requirement, for the simple reason that linseed oil soaks up water. I am not prepared to tell you what kind of paint to use, except that it should be mixed with a nonporous material that will not absorb water. There are several kinds that might be tried. I understand that pure asphalt mixed with bisulphide of carbon is a very good paint. Then there are several paints undoubtedly made up of some mixture of carbon, possibly combined at very high or very low temperatures, that are apparently waterproof and stand working up and down in water very well. To my mind you ought to get that sort of a paint next to the metal of the holder. It would surely be of great benefit in

building holders to get some standard specifications of the essential features and the limit of strains so as to eliminate that impetus to builders to cut weights in order to secure the contract. If you simply settle such matters on the basis of the lowest bid in dollars and cents you may be pretty sure that the tendency of the builders will be toward cutting the specifications. Answering Mr. Doty's question about gauges in the side of the holder and in the crown, as far as the gauges in the sides of the holder are concerned, it is largely a matter of getting enough metal there to stand the wear and tear and corrosion. The tension on the side sheets of the holder, unless it be very large indeed, is within any ordinary gauge. In the crown it is a different matter; there the bursting strain to be taken care of is greater, varying comparatively as the diameter of the inner lift is to radius of the crown, and in heavy holders the crown usually requires a heavier gauge than the sides. Mr. Norris spoke of the pressure of the inner lift. As a general thing the correct design in construction of the inner lift of a small holder would give you a minimum of about 31⁄2 inches. It does not pay to put metal in the inner section simply to secure an abnormally high pressure. Sometimes, even though the gas company has plenty of room to put in the most economical proportion of holder, yet requires a very high pressure on the inner lift. To put in the metal to secure this pressure is quite an expensive matter. It seems to me better to build the inner section right, letting the pressure come as it will, then if it is not sufficient for your distributing system secure whatever pressure is necessary by means of an exhauster or fan. As much force would be required to put the gas into a heavy inner section as would be expended in the other plan.

On motion of Mr. Howard a vote of thanks was tendered to Mr. Carpenter for his interesting and instructive paper.

The President introduced Mr. George F. Goodnow, of Waukegan, Ill., who read the following paper on

DISTRIBUTING GAS AT HIGH PRESSURE.

After reading a paper upon this subject before the youngest Gas Association in the country, the Wisconsin, and presenting another a week later before the mother of all Associations, the New England, at Boston, both in the month of February last, and listening to the objections, comments and questions which followed, as well as reading the correspondence which followed, from old Salem to new Seattle, the writer became convinced that there is a widespread interest among the gas fraternity regarding