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

MAy 16, Igor. MULTIPLE-CYLINDER ENGINES. The author compares the advantages and disadvantages of expanding steam in more than one cylinder, as compared with expansionina single cylinder. When steam engines were first employed on a practical scale to drive industrial works, the system of expanding the steam in two cylinders was introduced, though the object to be obtained in so doing was not fully appreciate1. Asthe enginesin use at that time were beam engines, one of the main reasons put forward was that it gave a more regular turning effort than when a single cylinder was used. It seems, however, looking at the types of engines which followed these, that an effort was made to obtain a wide range of expausion without altering the existing imperfect means of steam distribution. The author traces the various stages of development of the com- pound steam engine up to the time when modern research demonstrated its economy, but thinks that in spite of the labors of modern experimenters the information relating to this type of engine is not very complete. He then refers to the advocacy of quadruple and quintuple expansion by some engineers, based on the assumption that the more the difference of pressure, and consequently the fall of temperature, in each cylinder was reduced, the less became the internal condensa- tion and the consumption of steam. Experience, however, does not always bear this out, and usually expanding three times is considered sufficient. He refers to the uncertainty that existed as tothe correct ratios of cylinder volumes, which today usually vary from 2.6 to 3 for the ratio of the intermediate to high-pressure cylinder, and thinks that practice has had more to do with determining this ratio than theory. He then passes to examine the different methods of utilizing the steam in order to give a minimum consumption per indicated horse-power. To do this he makes use of the same data he has already employed in a former paper on single-cylinder engines; but in order to establish a comparison between multiple-cylinder and single-cylinder engines, he assumes than the expansion of steam follows Mariotte’s law, which is far from being the case in multiple-cylinder engines. Under these conditions, he calculates the steam consumption per indicated horse-power per hour, assuming the different values for 1, ratio of cylinder volumes; 2, cut off; 3, initial pressure of steam in cylinder; and then com- pares under these conditions engines on the Wolf system and those with two or three cylinders. Various tables are given in the paper read before the Société d’ Encouragement, show- ing the influence of the several points. If the results for two-cylinder compound engines are examined it will be seen that a diminution of cylinder satios corresponds, I, to an increase of power developed by thesteam in the first cylinder; 2, to a corresponding diminution in the second cylinder; 3, to an increase of the total power developed by the two cylinders; 4, toan iucrease in the weight of steam condensed in the first cylinder; 5, to adiminution of the weight of steam condensed in the second cylinder; 6, but the total amount of water con- densed shows no diminution. A closer investigation seems to show that cylinder ratios varying between 2 and 4 are best as regards utilization of heat. A consideration of the influ- ence of various points of cut-off shows that for a given cylin- der ratio there is a point of. cut-off corresponding to a mini- mum consumption of steam. In the third part of the paper the author discusses number of diagrams taken on multiple- | cylinder engines, and compares the results of this examina- tion with his calculations. He concludes by stating that although it is true that by employing two or more cylinders to expand the steam in, the fall in temperature in each is reduced, and consequently the internal condensation should falltoo, Yet, on the other hand, the cooling surface in con- tact with the steam is increased, so that what is gained by decreasing the range of temperature is more than counter- balanced by theincrease of surface in contact with steam. It is from this cause that the steam consumption of a co n- pound engine may be higher than that for a single cylinder engine. He considers that the loss from condensation is largely due to the difficulties of obtaining the best possible steam distribution witha singleslide valve, and itis this that has led tothe introduction of improved independent valves on single-cylinder engines. —Iustitution C. E., Foreign Abstracts. DO SOOO OS THE OLD AMERICAN CLIPPER SHIPS. In the early forties the Ameficans turned out some very fast ships for the China and other foreign trades, Freights between New York and San Francisco were then up to $35 and $40 aton. The Flying Cloud, built by Donald Mackay at East Boston, in 1857, made 433% statute miles in one THE MARINE RECORD. day, noon to noon, being slightly over 18 miles per hour. The Sovereign of the Seas, from the same yard, received as freight on her first voyage from New York to San Francisco $84,000. In her second year she made 6,245 miles in 22 days, nearly 12 miles an hour all through. The American clipper ship Surprise took outward cargoes from New York to San Francisco, made her way to China, and loaded tea at Canton for London. Her receipts for the round voyage paid her entire cost and running expenses, besides leaving a profit of $50,000 (her freight from Canton was $30 a ton). One of the Baltimore clippers, the Architect, secured in 1854 no less than $40 a ton freight from Canton to London. The success of the American vessels stimulated the energies of British builders. Mr, Richard Green’s Challenger was pitted against the American clipper Challenge from Anjer home, and ship was staked against ship. The British ship beat the American by two days, making the passage in 62 days. Ref- erence in a volume just published on this subject, is made to the Lord of the Isles, the Titania, the Ariel, the Fiery Cross, the Serica, the Taeping, the Taitsing the Thermopylz, the Cutty Sark, the Sir Lancelot, and other famous British clip- ‘pers. S ntnEEEEEEEEEREEeee cet HEAD OF THE LAKES COMMERCE, The RECORD has just received the official report of lake commerce at Duluth and Superior for the navigation season - of 1900, with comparisons of commerce of previous years, as kept by the U.S. Engineer Office, Duluth, and compiled under the direction of Major Clinton B. Sears and Captain D. D. Gaillard, Corps cf Engineers, U. S. Army. AMOUNT OF FREIGHT RECEIVED AND SHIPPED, PRICE PER UNIT, AND VALUATION OF SAME, DULUTH, MINN., AND SUPERIOR, WIS., COMBINED. PRICE DESCRIPTION OF CARGO. | QUANTITY] PER | VALUATION UNIT. Coal, Anthracite, net tons. 643,179) $ 5 2516 3,376,690 ‘* Bituminous, ‘* ‘‘ 2,029,398 3 30 6,697,013 Limestone, ee ae 39,956 I 80 71,921 Salt, bbls..... 305,883 90 275,294 Mach’y, all kinds, net tons 332| 300 00 99,600 Manufactured Iron, ‘* ‘ 53,228] 609 00 3,193,680 Kerosene Oil, bbls. .... 108, 146 5 80 627,247 General Mdse, net tons 233,881} I00 00] 23,388,1c0 Logs, 1,000 ft. B. M....... 75,142|. II 00 826,562 Fish, - net tons 745; 70 00 52,150 Cement and Lime; bbls... . 180, 166 I 4o 252,232 Building Stone, net tons 6,906 6 50 44,888 Other Stone, Gs gl 1,250 75 938 Sand and Gravel, cu. yds. 30,141 50 15,070 Iron Ore, net tons} 5,979,740 2 25) 13,454.415 Copper, eo 67.344] 340 00] 22,896,960 Flour, bbls....| 5,949 o12 3°75| 22,308 795 Wheat, bush...| 30,776 404 70} 21,543,483 Other Grains, etc. ‘* ...} 12,960,154 70 9,072,108 Structural Steel, net tons 836] 75 00 62,700 Wool, Stee 7,348] 260 00 1,910 480 Lumber, 1,000 ft. B. M. 323,901| 14 00 4,534,614 Shingles, M.No........ 175.327 I 00 175.327 Lath, Sa ri arate 30, 567 2 00 61,134 Ties, Pe Ne eanee 559,318 30 167,795 Total, $135, 109, 196 In addition to the foregoing, it is noted that the total number of vessels entered and cleared during the 234 days of open navigation, was 11,334, of which 9,512 were steam- ers and 1,822 sail and tow barges, having a total registered tonnage of 14,387,068, and an average or mean tonnage of 1,443 for each vessel, exclusive of tugs. Even these large figures show a decrease in the valuation of cargoes received and shipped of $22,034,770 as compared with the previous season, when the aggregate valuations amounted to $157,- 143,966 for 11,608,088 tons, as compared with 11,725,245 tons for the season of Igoo. ~ The total number of passengers arriving and departing was 62,933, an increase of 6,723 over 1899, and 27,191 over 1895. The average number of tons of cargo received each day was 13,142 and of shipments 36,923 tons, thus making a total amount of 50,065 tons of cargo handled daily through- out the season of navigation. Relative to the valuation of the different commodities, wheat and other grains show a decrease of 22,998,505 bushels, with a valuation of over $18,000,000 less than 1899. Anthracite coal shows a decrease of 328,557 tons with a valuation of over $1,700,000 less than in 1899. Iron ore shows an increase of 1,054,685 net tons over 1899. The total traffic of 11,725,245 net tons shows an increase of 117,157 tons over 1899. SHIPPING AND MARINE JUDICIAL DECISIONS. (COLLABORATED SPECIALLY FOR THE MARINE RECORD.) Usury in Bottomry Bond not Illegal.—A Ioan secured by a bottomry bond is not affected by the usuary laws, since the lender is the insurer of the vessel for the voyage to the extent of his loan. Theo. H. Davies & Co., Limited, vs. Soelberg et al., 64 Pac. Rep. ( Wash.) 540. Personal Security in Conn ction with Bottomry Bond.— A bottomry bond cannot be given in connéction with personal security by the owner of the vessel to pay the debt regardless _ of the return of the vessel to port. Theo. H. Davies & Co., Limited, vs. Soelberg et al., 64 Pac. Rep. ( Wash.) 540. Maturity of Bills of Exchange for Bottomry Bond.—Bills of exchange may be given in connection with a bottomry bond as representing the debt so secured, but such bills will not mature until the vessel returns to port. Theo. H. Davies & Co,, Limited, vs. Soelberg et al., 64 Pac. Rep. ( Wash.) 540. Seam 2sn—Wages.—A seaman, who signed articles before a shipping commissioner at a distance from the vessel, to which he was furnished transportation, arriving on the same day at 6 p. m., held, to be in the service of the ship that day, and entitled to wages therefor. The Alice B. Phillips, 106 Fed. Rep. (U. S ) 956. Court of Admiralty—Finding of Fact Presumptively Cor- rect.—A finding of fact by a court of admiralty upon con- flicting evidence will not be reversed or modified by an appellate court unless there is a clear preponderance of evidence against it. Elphicke et al., vs. White Line Towing Co., 106 Fed. Rep. (U. S.) 945. Bond to Secure Bottomry Bond Invalid.—Where a bottomry bond is accepted as security for an advance by the lender, subsequent bond by the owner of the vessel, given to = secure such sum and in consideration thereof, is invalid for want of consideration.—Theo. H. Davies & Co., Limited, vs. Soelberg et al., 64 Pac. Rep. (Wash. ) 540. Bottomry Bond—Creates No Personal Liability.—A bot- tomry bond is an obligation in the nature of a mortgage on a vessel to secure necessary moneys or supplies for the con- tinuance of a voyage, which can be procured in no other way, and does not create a personal obligation on the owner. - till the vessel reaches port. Theo. H. Davies & Co., Limited, vs. Soelberg, et. al., 64 Pac. Rep. (Wash.) 540. Seamen—Wages—Overtime.—Seamen serving under entire coutracts, either by the month or for the voyage, are not en- titled to lien on the vessel for overtime on account of services rendered on Sunday or at night, where the work performed was not outside their proper duties under their contracts, notwithstanding a promise by the master to pay them for such overtime. The Northern Light, 106 Fed. Rep. (U.S ) 748. Seamen—Wages Recoverable—Right to Discharge .on Vessel becoming Disabled.—A vessel which is so injured by _ encountering oridinary perils of navigation as to be unfit to complete the particular voyage commenced, is ‘‘lost or ‘wrecked,’’ within the meaning of Rev. St. U. S. 2 4527, and the seamen employed for such voyage may rightfully be dis- charged on her return to port of departure, and are entitled to recover wages only for thetime actually served. The Charles D. Lane, 106 Fed. Rep. (U. S.) 746. Shipping—Injury of Stevedore—Liability of Ship.—Libel- ant, who was employed by stevedores, and engaged with | others in stowing cotton in the hold of a ship, was injured by the rolling against him of bales of cotton lowered by the winchman upon those lying under the hatchway. Held, that in the absence of evidence to sustain allegations of the incompetence of the winchmanto which the libel charged the injury, or to establish any improper or unskillful act on his part, the ship could not be held liable forthe injury. The Anaces, 106 Fed. Rep. (U. S.) 742. Voluntary Signing of Release.—A vessel, soon after start- ing on a voyage, became so disabled in a storm as to be un- able to proceed, and jettisoned a portion of her cargo, and returned to the port of departure for repairs, where the mas- ter discharged the crew, and paid them their wages for the time served. The men protested that they were entitled to a month’s pay, but without compulsion accepted the money tendered, and signed a full release in the presence of the shipping commissioner. Held, that they were bound by such release, and could not maintain a suit against the ves- sel for additional wages. The Charles D. Lane, 106 Fed. Rep. (U. S.) 746. Collision—Excessive Speed—Fog.—A tug returning from sea with two dumps in tow on a hawser collided at about 12 midnight, in a thick fog, witha ferryboat. Both boats gave proper signals, which were heard by each some four or five minutes before the collision, which occurred at about right angles. Each claimed that his own boat was stopped at the time of the contact. This evidence was rendered improba- ble from the severe injuries suffered by both vessels. The lights of the colliding vessels were discovered at a distance of from I00 to 200 feet. Held, that both vessels were in fault, in not sufficiently reducing their speed so as to have been able tocometo a full stop after the discovery of the lights. The West Brooklyn, 106 Fed. Rep. (U. S.) 751.