The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

1900.] MARINE REVIEW. as Summing up, we have the following as the WORLD'S OUTPUT OF COAL (1899). Tons. United: Winedom isos ae ee eee 220,085,000 British FOssessions: 2.1, ...2.. 6 es 16,865,000 whotal: British: mpire hie eG eee is eo wa 236,950,000 Foreien countries See iee Pe See Pe RA A 419,823,000 Foréien: Gignite) 2 chavtns eh sie. ses eee ce ee oe ee 63,896,000. . Grand total 2300 ee 720,669,000 Deduct. lnemite \ 20h AE ea ee a es ca 63,896,000 Total ordinary Gal 205) a oe 656,773,000 This is at least 60,000,000 tons more than was ever 'before produced in any one year. Yet it has all gone into consumption, leaving the world unsatisfied. Of course, the consumption, both in gross and per head of population, is naturally greatest in those countries which make most use of steam traction and of steam machinery. But, while the largest aggregate con- sumption is in the United States, the proportion per capita is higher both in the United Kingdom and Belgium, in which coal is practically the only power-raiser. In Aimerica there is a large employment of other fuel, and of water-power. Yet the consumption there of coal is simply enormous. The following shows in the principal countries the COAL CONSUMPTION, 1899. Quantity. Per capita. Country. : Tons. Tons. Winited States... ak ek epee 193,497,000 2.60 Wnited Kanedoms 12 ...050 a 153,798,000 3.83 Germany, si244 68 bc Noe Gane - 88,141,000 1.62 Below cake sen ees 18,349,000 2.75 Hrances sas re eS 40,921,000 1.06 Austria-Hungary 3) 35. on ee 17,171,000 0.37 Russia a Ll 4000 0.11 tay ee ee eee ee 4,414,000 0.14 Sweden in bo ee a ee 2,694,000 0.53 SPAIN. 6 sie 4,429,000 0.19 Indias 6 ose 6 eae a 4,657,000 0.01 @anada <3 oy Ba Sees eee 6,625,000 1.37 New South Wales 3... ew a 1,915,000 1.42 NaCtOLia (a. a ee ee 805,000 0.68 New Zealand 3.3.65 2 ee. 957,000 1.29 Cape Colony, eo. 385,000 0.20 Note----In the case of the United States and Russia lignite is in- cluded, not otherwise. Some of these figures relate to 1899, and some to 1898, returns not being all to the same date; but they give a fair view of the relative posi- tions. It will be seen that the countries consuming more coal than they produce are France, Russia, Sweden, Spain, Italy. Austria-Hungary, Can- ada, Victoria and Cape Colony. The only countries which have absolute surplusses over home consumption and imports are the United Kingdom, Germany, Belgium, Japan, the United States and New South Wales.-- Fairplay. WATER TUBE BOILERS. THE FIRST LORD OF THE ADMIRALTY REPORTS UPON A SERIES OF EXPERIMENTS IN THE BRITISH NAVY--THE BELLEVILLE BOILER DEFENDED. Mr. Goschen, first lord of the admiralty, submitted recently to the house of commons a memorandum respecting water tube boilers in the British navy. The memorandum is the result of a series of experiments extending over a period of three months and is most exhaustive in its character. In it he maintains that the lack of success on some ships with the Belleville boiler has 'been more personal than structural. The experience gained with small tube boilers up to the present in destroyers, torpedo gunboats and third-class cruisers does not, in the opinion of the admiralty, justify their use in larger ships, though they have been adopted for the purpose in the French and some other foreign navies. It is stated that there are substantial advantages in adhering, as far as possible, to one principal type of boiler for all ships, as the whole service becomes quicker accustomed to its use, artificers, both in the ships and dock yards, become more expert in its repairs, and there is to a certain extent interchangeability of the spare parts and accessories which have to be kept in store. Trials have been made with Babcock & Wilcox and Niclausse boilers for comparison with Belleville boilers, but the trials showed no decided advantage of either over the Belleville boiler. These experiments were considered to justify further trials, and it has been decided to fit the Babcock & Wilcox in one of the new sloops, and possibly in one of the new second-class cruisers, and the Niclausse in a new sloop and in a first-class cruiser of the Monmouth type. A comparison is made between the trials of the Highflyer and Min- erva as forming the most direct comparison the admiralty have yet been | able to make between the performances of Bellevlile and cylindrical boilers under ordinary sea-going conditions. The Minerva is fitted with cylindrical and the Highflyer with Belleville boilers. On the first sixty hours' trial at 10 knots the Minerva developed 1,083.8 indicated horse power, steamed 9.84 knots, and consumed 2.88 pounds per indicated horse power for all purposes; the Highflyer developed 1,190.5 indicated horse power, and steamer 9.8 knots on 3.46 pounds of coal, but owing to leaks, etc., one boiler was out of use 434 hours. On a run of 60 hours at 14 knots the Minerva with 3,028 indicated horse power consumed 2.33 pounds of coal per indicated horse power, and the Highflyer with 2,831.5 indicated horse power 2.90 pounds. On the first 30 hours' trial at the highest power obtainable the Minerva on 7,550.2 indicated horse power attained 17.53 knots on a consumption of 2.28 pounds (on this trial the forward main feed suction pipe burst); the Highflyer on the same trial indicated 7,946.8 horse power, and steamed 17.9 knots on a consumption of 2.52 pounds per indicated horse power. During the earlier trials the coal ex- penditure in the Highflyer was found to be very much in excess of that in the Minerva, and so large, compared with the results obtained on her contractors' trials, as to indicate either serious defects or want of skill in the management of the fires. The inspector of machinery was therefore sent on board, and after the stokers had been trained for 24 hours the - first trial: was repeated, with the result that the expenditure of coal was reduced from 3.45 pounds to 3.16 pounds per indicated horse power. It was afterwards found that the low-pressure slides and faces were much 'worn and not bearing satisfactorily, which would.account for considerable officers and enlisted men on ships of war in commission. loss of economy. After refit her expenditure of coal was, on a trip from Malta to Gibraltar (1,023 miles), 2.67 pounds per indicated horse power and her speed. 13.16 knots, while that of the Diana, a similar ship with cylindrical boilers, at 12 knots, was 2.94 pounds, the former vessel burning 16 tons of coal Jess than the latter. The trials at the highest speed ob- tainable showed an advantage in speed on two trials of 37 and .94 of a knot in favor of the Highflyer. The Minerva's machinery, with cylin- drical boilers, would 'have to be from 47 to 170 tons heavier to give this increased power. It is stated that economy largely depends on the stok- ing, and on the boiler being free from deposits, and in all respects in good order, but in many cases where the coal consumption has been large it has been found to be mainly due to defects in the machinery which, under the conditions of naval service, are very difficult to discover, the vessels being always kept as far as possible ready for immediate service. 'By the adoption 'of water tube boilers the steam pressure was increased from 150 to 250 pounds, which involved alterations of detail in the designs of practically all the auxiliary machinery as well as the main engines. The advantage of quick raising steam was, it is stated, illustrated in the case of the Niobe at Las Palmas when the Persia transport broke her shaft and was nearly 'on the rocks. The Niobe was able to get up steam and go to her assistance in 134 hours from the time of receiving the news. With cylindrical boilers it would have required five or six hours. The following is taken from the conclusion in the memorandum: Surprise is naturally felt by those who are not fully conversant with the whole of the circumstances that difficulties connected with the man- agement of water tube boilers and high pressure machinery should take so long to overcome. A little consideration will show that up to the present, and for some time to come, the engine room staff of every newly com- missioned water tube boiler ship must be largely composed of those who have had no previous experience of this type of machinery, as the number of water tube 'boiler ships in commission has up to the present borne so small a proportion to the total number of ships for which crews are pro- vided. 'Lhe rate at which crews can be trained will increase rapidly as more water tube boiler ships become available, and as special arrange- ments for training engineers, engine room artificers, and stokers augment the number of men with experience of these boilers. There is no doubt that the advance from cylindrical to water tube boilers, with its accompanying great increase in pressures from 150 lbs. to 250 libs. at the engines, has for the present added greatly to the anxieties of the engineers in charge of the machinery. This is inevitable when any change of this magnitude is made, involving as it does such a multitude of small details. It should be fully recognized that these officers have at first a difficult task, and that time is necessary to enable them to gain experience in the best way of dealing with all emergencies that arise under the new conditions. Men-of-war must be designed to cope with those of foreign countries that they may have to meet in war, and no country can afford to relinquish such a decided advantage in speed for a given weight as the trials of the Highflyer and Minerva showed to be given by water tube boilers, or the great advantage of getting up steam and increasing speed rapidly, unless there were strong grounds for supposing that the numerous defects in de- tails which now render the machinery somewhat less reliable than older and well tried types were likely to be permanent. 'This is certainly not the case. All the experience in our commissioned ships shows that the defects from which they at first suffered are being rapidly overcome, and it is practically certain that if we were to revert to 'cylindrical boilers and accept the sacrifice of speed or increase of displacement that it would entail, we should find that before the first ship was completed all the diff- culties of detail which now give us trouble in water tube boiler ships will have been overcome and all our new vessels would be distinctly inferior to those of all other countries, with no compensating advantages. Taking the results of the Highflyer's and Minerva's trials as they stand, and putting the 100 tons of weight saved in the machinery of the former into horse power instead of guns, the gain of speed due to the water tube boilers under practical sea-going conditions cannot be put at less than a knot, a result which is 'borne out in a general way by the com- parisons of other runs of vessels with cylindrical and Belleville boilers re- spectively, though in these cases equally precise conclusions cannot be drawn from them, owing to the form and dimensions of the ships com- pared not being identical. Thus, if the admiralty of the day had not de- cided to put water tube boilers into the Powerful when she was designed, or the subsequent successive boards 'had hesitated to follow their policy, and had waited until the whole of the minor difficulties involved in the change had been overcome, the magnificent fleet which has been built. building, and projected since that time, consisting of twenty battleships, twenty-two armored cruisers, ten protected first-class cruisers, and nine second-class cruisers, making a total of sixty-one ships, would have had at least a knot less speed than they now will have, or an equivalent sacri- fice would have thad to: be'made in other directions, which to gain a knot at the high speeds now necessary would.be very considerable in amount. During the week the navy department decided to place merchant crews on board naval colliers and to assign merchant captains to the command of those vessels. This action was taken at the instance of Rear Admiral Crowninshield, chief of the bureau of navigation, who has advised the secretary of the urgent necessity of employing commissioned i This mav be a step toward the abandonment of the collier system in the navy. It is understood that the bureau of navigation is in favor of chartering ves- sels for the transportation of coal instead of carrying colliers on the naval register. It is represented that much of the time these colliers are with- out cargoes and are under constant expense for maintenance. The Bancroft, 'which has 'been ready for service for a year at the Boston navy yard, may be placed in commission and sent to Central American waters.