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Harvard" with a great deal of interest, particularly as we have been running some very extensive tests on the turbine yacht Vanadis with the idea of determin- ing coal and water consumed. From our own experience, I 9 am strongly of the opinion that the meter readings as given by Prof. Peabody are incorrect. We ran three separate tests on the Vanadis, and had installed a Neptune water meter in the feed line which had been previously calibrated by the meter company In the last of the three tests when the working parts of the meter were in perfect order before and after the tests, we got the following result: Coal. per hour, 3,086 pounds as a mean of 24 hours, Water by meter pounds. Water by actual measurement in bar- rels, 29,188 pounds. The measurement in barrels was a measure of all .water passing through the condensers for a period of 45 min- utes, during which time we_ actually handled 21,891 pounds. of water. The water in the barrels was measured with a measuring stick, the barrels having been previously calibrated by filling on the. | scales. : We were using the same coal as used by the Metropolitan line, or possibly a little better quality. Prof. Peabody's evaporation shows over 11 pounds. Our calorific test of coal gives us slightly over 14,000 British thermal units, which makes me feel that the boiler efficiency, as apparently deter- mined on the Harvard, is away beyond what we can reasonably expect. On the other hand, I think we have a right to expect far better turbine efficiency than 16 9/10 pounds per hour at the speed at which these ships are running. Of course, this does not affect at all the question of coal per shaft horsepower hour, but I think it will be too bad if the average engineer, on the basis of these figures, should figure on obtaining anything like the evaporation stated from _ ordinary American coal. The President: The paper is now open for general discussion. REMARKS BY W. CARLILE WALLACE. W. Carlile Wallace: I have read this paper with. considerable interest, and there are one or two points which I would like to comment upon. In the first place, I would kke to know how the B. T, U. per shaft horsepower per minute is arrived at. This figure 265.9 seems to me to be incorrect, unless I am mistaken in the way it is arrived at. Now, with regard to the remarks of some other speakers, I notice in this per hour, 34131 THe Marine REVIEW paper we are not given: the calorific value of the coal. This appears to me to be a decided omission, because the boiler efficiency is a very important one, and it is entirely neglected. On the other hand, I do not agree with some of the other remarks that it is impossible to get an evaporation of 11.2 per pound of coal, at 212 degrees, with good Scotch boilers. That I have gotten, and con- siderably more, at the rate at which they were burning in this case. In this case the coal is very bad. Another point is that the moisture in the coal is not given. Of course, when the calorific value of the coal is not giv- en, the moisture is of no account, be- cause you cannot do anything with one without the other. As to the use of the water meter for a really scientific test, in my opinion it is utterly valueless, but unfortunately at sea it is difficult in service to get any other way of measuring the water, The only real way, of course, is to measure the water very carefully in tanks, and in that way arrive at an absolutely accurate weight, or weigh the water. That, .of course, would be an impossible under- taking with the amount of water that is - used. With regard to the coal measurement, it is possible to arrive at a fair estimate of coal if great care is taken in strik- ing off the buckets carefully, but the most satisfactory way for trials is to have all your coal weighed carefully in bags, put on the plates, or let down as the coal is burned. Of course, it is a troublesome and expensive method, but - you get accuracy as far as.the weight is concerned, and then again there must be great care taken in estimating the coal both at the time of starting on the bars, and at the time the trial is over, and that) 3s' a very. frwittil 2 case ot error. WATER METERS IN MARINE TESTS. E. A. Stevens: I had occasion to use water meters in marine tests, and I have found in calibrating them before and after the test that the two calibra- tions very rarely agree. ' The tempera- ture of the water seems to effect most of the meters. The ones I got the most satisfactory results with were some old- fashioned Worthington's, positive dis- placement meters. As to the general criticisms on this paper, I want to say a word as to the methods under which such tests usually have to be conducted, somewhat in the line of what I wrote about trial trips yesterday. The observer is generally at a considerable disadvantage in conduct- ing a trial on a ship which is at business ard working and earning money, and at- 17 tempting to make any tefined test on her. The demands of the service are such, as usually to forbid going into such refinements as the weighing of coal. I tried to do that in several cases, in trying to get at. the actual service con- sumption of the trip, but the service of the vessel and the cramped room avail- able has generally been such as to render accurate weighing impossible, and weigh- ing merely resolves itself into a system of verification of previous estimates, made on some other basis, such as I pre- sume these were made on. I quite appreciate also the absolute im- possibility of working a system of tanks on vessels in service with the room I have ever found available for that purpose. Of course, Mr. Barrus' remarks © as to the character and scope of the plant, and the information conveyed by knowing its dimensions, are perhaps a well founded criticism, but it is not al- ways possible to get these details and publish them, I do not know whether that is so in this case, but I know in other cases in which I have been inter- ested, the builders or owners, for some reason or other, have refused to allow the publication of such details. Robert McGregor: My official capac- ity in connection with the steamers Har- vard and Yale, in operating this season, I will say that we commenced the season on May 11 and closed on Noy. 8, mak- ing 178 trips. It seems to me that the chief point of contention in this discus- sion is the question of coal consumption, and how the amount is arrived at. Any man knows the absolute impossibility of trying to weigh out every package of coal, and expect to get accurate results. I. have taken. 178 trips;. and on tis service each trip is practically the same. It gives a consumption of 7.10 tons of coal per hour on the steamer Harvard, as against 7.04 of coal per hour on the steamer Yale. Now, this amount of coal is coal which is actually paid for, and it is not my experience in New York that you get any more coal in weight than you pay for. (Laughter.) I was present at the test made by Prof, Peabody, and I consider the care -- and experience shown in that test as re- flecting great credit on all concerned. The representatives of the institute were aboad the vessel for a week in testing and applying apparatus, and personally I consider the results fairly accurate. -- Speaking of the steamer Harvard, I might mention that during the whole season we have not had any trouble whatever with the main engine and tur- bines themselves. In comparing this class of engine with reciprocating en- gines, I might say in my opinion it is as