materially brought down; but if you mix it with lime no inconvenience of that sort would be experienced.

MR. HARBISON-In that respect Mr. Somerville reports a different result from that detailed by Mr. Spice.

MR. SPICE-I do not know how Mr. Somerville tried his experiment; but my statement of experience is the result of two years' working.

MR. HARBISON-I am trying to get around the difficulties experienced by Mr. Somerville in his month's working. I infer from the remarks of Mr. Spice that that gentleman has conquered the difficulties as they were encountered; and as a consequence he does not now have them to contend with. As to Mr. Spice's remarks about everything being covered over with lime dust, I must say that I do not find, in our lime room (where we are using oyster shell lime), that the men get covered with it as a consequence of handling it dry. Would it be sufficient to take the specified quantity of lime and sprinkle it over the coal; or must it be thoroughly mixed with the rake?

MR. SPICE-We use a charging machine; and a part of that apparatus involves the use of a coal breaker. A man fills a barrow with coal, turns it over into the coal breaker, and then puts a shovelful of lime on top of the coal just as it is going down. That is all he has to do.

MR. HARBISON-Is it necessary to use oxide with the liming process?

MR. SPICE-That is not a hardship, but rather a blessing. It is not a necessity, but that is a part of the story. You use no lime except that which goes into your coke. Instead of the lime being sent away as useless when taken from the purifiers, it goes to market-you sell it with your coke. By reason of the lime addition the weight of your coke is increased 21⁄2 per cent.

MR. HARBISON-If you were to sell the coke by measure there would not be an advantage?

MR. SPICE-There would be no money result gained therefrom, but the quality of the coke would be improved.

MR. HARBISON-What effect has the liming process upon the life of the retort?

MR. SPICE None whatever. That is the last thing to imagine. The first thing that we found any difficulty about was in the deposit of a dusty material in the flues of the furnace. This dusty deposit merged gradually into a hard substance that tended eventually to choke up the flues. We had to blow them out more frequently than was the case before.

MR. HARBISON-Was the deposit caused by the admixture of too great a quantity of lime with the coal?

MR. SPICE-Not because there was too much, but because of the very presence of the lime there. It presented no difficulty when we understood the nature of the deposit. When my attention was first called to it I said there could be no effect without a cause, and I asked my manager if he had considered the causes. He replied in the negative. I examined the material and divined the cause. I directed him to blow out the flues. In the course of the week he reported what improvement had been made. By the end of the week the heats were as good as ever, and so also were the retorts. I told him he was using a new form of coke, or one with lime in it, which tended to form a mass something like cement; and that the deposits were blocks of solid matter which would not have become solid if he had blown out the flues oftener than had been his former custom.

MR. HARBISON-What does Mr. Spice find is the yield per pound? And what is the effect upon the illuminating power of the gas?

MR. SPICE-The illuminating power is not affected in any way. The yield is about 10,200 feet per ton of 2,240 pounds of Newcastle coal-which is considered very good working. We have not found that our annual make has been affected in the slightest degree by the use of this process; but we have found, as a result of critical examination, that there is a loss of illuminating power to the extent of 0.2 of a candle only-a consequence of the admission of air to effect the revivification of the oxide in situ. As gas men we would call that nothing to speak of.

MR. HARBISON-I am not sure that I remember the precise statement in his paper as to the cost of slaking the lime and mixing it with the coal.

MR. SPICE-In the absence of apparatus similar to that in use at our works, it has been found to cost one-half penny per ton. It added just so much labor to the coal wheeler. As a practical test, I found that, for the year 1884, instead of having used 21⁄2 per cent. of lime, (which is the prescribed quantity), we had used only 24 per cent. That was as near as a man could work. You must understand that we have not weighed it at all. We found, by practical experience, that a shovelful of lime to a barrow load of coal was the proper mixture.

MR. HARBISON--As Mr. Spice has said, the gas works in this country using mechanical appliances in charging and drawing retorts are quite exceptional. There are only two or three places in America where the work is done in that way. The handling of the lime—slaking it in one building and bringing it into another -has to be done by manual labor. Could he give us an estimate as to what would be the cost under such circumstances?

MR. SPICE-In England we found the labor charge to be about one-half penny per ton. You might put it at one penny if you like. It is nothing serious, though.

MR. ENFIELD--Has the lime process any effect upon the deposit of carbon in the retorts?

MR. SPICE--None whatever.

MR. FULLAGAR-What would be the effect if some of the lime were deposited on the tar in the hydraulic-the tar being light, and working no seals?

MR. SPICE--We never had any drawn up the ascension pipes. Your idea would have a foundation of practical value if you assume that dry lime were being put into, the retort. You must bear in mind that this equal weight of water stops all that. The lime is laid hold of in the retort.

MR. HELME-I would like to ask Mr. Somerville if he used oxide of iron alone?

MR. SOMERVILLE-No; I used part oxide and part lime.

MR. LANSDEN-I want to understand the cause of this difference between Mr. Somerville and Mr. Spice. Does not Mr. Spice use the coal in a much finer or pulverized condition; or can we in this country, with our lump coal, use it in the same way that he would use the Newcastle coal? Would not our coal have to be crushed?.

MR. SPICE-No; your nut coal would do very well. The largest lumps of coal would need to be broken up; and perhaps the smaller the coal is the better would be the result. Still, it is a question of degree-affecting not the grand results, but the exact results of the sulphur compounds. You would not have them so much reduced if you only whitewashed your lumps of coal and put those whitewashed lumps into the retorts. It is a question only of degree. It is only a question of reducing the sulphur compounds with greater or less efficiency.

MR. HARBISON-Would the same result be obtained if the lime was not mixed with the coal in the retort house?

You would spoil your

MR. SPICE-I would prefer to mix it. coke by having great blotches of lime on it. The lime should be evenly distributed. The consumers might object to a large patch of lime on the coke.

MR. HARBISON-I would like to have Mr. Somerville tell us (a little further than his paper does) what his personal impressions are with regard to this matter; or as to what causes the difference in the results obtained by him and those obtained by Mr. Spice.

MR. SOMERVILLE-I would like to state it was with great regret, and in fact with some mortification, that I failed in this thing. When I started in I did so in good faith; and in the hope that the sulphur compounds could be decreased, and the amount of ammonia be increased, to the extent that Mr. Spice has said. It was an important thing to me. I was turning the ammonia into sulphur, and I did my very best to make the experiment a success. I broke the coal up very fine; in fact I used what is called slack coal for the purpose of thoroughly mix

ing the lime with it; for I understood that a great deal of the success of the experiment depended upon this thorough intermixture. I have stated the results. I will state where I think that Mr. Spice gets his extra ammonia-for it was the extra ammonia that I was driving at. The water that goes in with the lime helps, to some extent, no doubt, and the nitrogen of the air which he draws in also helps to make ammonia. I think there can be no doubt about that. Then, as to the purification. Of course, the lime going in with the coal purifies, to a certain extent, the crude gas. There can be no doubt about that either. Then, with the most elaborate and thorough scrubber purification which they practice in England-thus taking out a large percentage of the carbonate of soda and of sulphuretted hydrogenthere is very little work left for the oxide of iron to do. molecule of one per cent. effects, just as Mr. Spice states, actual purification in the closed vessel. The oxide of iron is actually revivifying, it seems to me, by this method: First, the water gives nitrogenous compounds; next the entering air affords still more; and then the scrubbing, taking out a large proportion of the impurities, leaves very little for the oxide of iron to do.

This

On motion, votes of thanks were tendered to Messrs. Somerville and Spice.

The next paper read was that contributed by Mr. John C. Pratt, of Jamaica Plain, Mass., on the subject of

THE PRESENT STATE OF THE GAS INTEREST.

The author read as follows:

Three years ago I had the honor to read before this Association a paper giving my views on the "Future of the Gas Interest." As some of you may remember, I prefaced that paper with an apology for presenting and advocating a policy, that had not been recognized by the gas interest of the country, which very likely would not receive your cordial assent and approval, as proved to be the case.

Still the discussion that ensued, and the criticisms that were offered, though keen and incisive, were in the kind, gentlemanly and courteous spirit ever characteristic of the discussions of this Association.