retort provided with its own condensing system. Under those circumstances we could probably regulate our conditions fairly well and obtain results much more quickly than we otherwise could, and I am quite confident that those results could then be applied to the full-sized plant and be found applicable.

I have to thank the Association and the gentlemen for the very cordial support which we have everywhere found in conducting the experiments we made. Wherever we have been at the different works there has been the utmost courtesy shown, and we beg to thank the Association for it. (Applause.)

Chairman-Prof. White, I do not know that I ought to call on you for anything more, but I would like to ask what percentage. of tar you have found in the gas-percentage of the total tar produced, you found in the gas at the entry to the scrubbing system, in those experiments, os is it given?

Prof. White-It is not given in so many words, but only one to three per cent of the total tar produced ever gets as far as the scrubbers.

Chairman-The reason I asked is, it seems to be very difficult to eliminate all the tars-tar vapors after the use of water or ammoniacal liquor, in some manner. It is evident from what you have been doing this year that to eliminate any tars with ammoniacal liquors is something we will look upon as a distinct question. If we can get all those tars out by mechanical means it would seem that we would be largely at the end of this trouble. As I take it, from the result of the work this year, there is something that I do not think has ever been determined before. Still, as you suggest, a man would not think of correcting the conditions under his reading lamp; I think that is one of the things we will have probably to study under the same reading lamp.

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It

I had a discussion with Prof. White a few days ago in respect to some proposed apparatus for the University. You could conduct this work in a little more systematic manner. was suggested last year that there should be an experimental plant put up at the University, making it possibly to a quarter size, provide a complete plant from the retort all the way through to the holder; and the University acted on that matter, and were far-sighted enough to say that they would find space and accommodation for anything that we would supply, and it is in such shape that it could be put in at any time, but it did not seem that that would meet the conditions which we were striving for. If the retort were quarter size the gas produced in the rear end of it would have only half the travel of gas in a retort such as we are using. We use about a nine-foot retort, because it is about as far as a man can throw coal. We would not want to use a horizontal retort because we would have a disproportion of invest

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ment to capacity. So, there are practical limits as to the size of the apparatus, and to produce gas in a retort which would not give the same conditions as a retort used in practice would be artificial conditions. It seemed to us that the present work for us-possibly looking at it from a commercial standpoint-would be to let the University endeavor to prevent some of the troubles which we have been having when they are producing under customary circumstances. It is now proposed, as Prof. Campbell suggests, to isolate three retorts in the Ann Arbor works. Mr. Douglas has kindly consented that this shall be done under certain conditions, which are exceedingly favorable to the Association. We are now endeavoring to devise apparatus which can handle a small quantity of gas and give it precisely the same treatment, actual and theoretical, which it would receive in a works. where a large quantity is handled. It may seem strange to some, but it would be a simpler process to handle a million feet of gas than it would to handle five thousand. However, we hope before another year to have something along this line accomplished. I think without further action on the part of the Association a vote of thanks will be entered upon the record to the Faculty for the work that they have done.