September 26, 1902.] 



SCIENCE. 



515 



them carefully on an analytical balance and 

 obtained the following figures : 



Weight of ant 3.2 mg. 



Weight of grasshopper 190.0 mg. 



Thus, the ant was dragging a load that 

 weighed approximately sixty times his own 

 weight. This is equivalent to a man whose 

 weight is 150 lbs. dragging a load of 4J tons, 

 or a horse of 1,200 lbs., a load of 36 tons ! Is 

 this not somewhat remarkable? 



Abmand E. Miller. 



WAVAL ENGINEERING. 

 The most extraordinary achievement in the 

 domain of fast yacht or torpedo-boat con- 

 struction has lately been reported as the out- 

 come of Mr. Chas. D. Mosher's work in de- 

 signing the high-speed steam-yacht. Arrow, 

 for Mr. Chas. R. Flint, of New York. On 

 the 7th of September this craft made a speed 

 of above 45 miles an hour on the Hudson 

 Eiver, making the mile in less than one min- 

 ute and twenty seconds. The measured mile 

 was established by the Coast Survey, which 

 sent its steamer Bache to fix its location some 

 time since. This performance exceeds by 

 three miles, nearly, that of the British tor- 

 pedo-boat destroyer Viper, with engines of the 

 Parsons type of steam-turbine. The latter 

 made 42.25 miles an hour, a mile in one min- 

 ute and twenty-five seconds. The Arrow is 

 but 130 feet over all, 12 feet 6 inches beam, 

 displacing 66 tons, on a draft of 4 feet 7 

 inches. The water-tube boilers contain 5,540 

 square feet of heating surface and the 

 quadruple-expansion engines are capable of 

 producing 4,000 horse-power. Maximum 

 steam-pressure is reported to be 400 pounds at 

 the boilers and 390 at the engines. The fol- 

 lowing table presents the records of recent 

 fast craft of this 'type: 



Consul J. E. Kehl sends to the Depart- 

 ment of State, from Stettin, a description of 

 the new North German Lloyd steamship 

 Kaiser Wilhelm II., recently launched at the 

 Vulcan yards in that city. The cost was 

 16,000,000 marks, and she is scheduled to sail 

 during the early part of April, 1903, between 

 Bremen and New York. He says: The 

 Kaiser Wilhelm II. is built according to the 

 German Lloyd requirements for the highest 

 register of the four-deck ship class. Her 

 double bottom is divided into 26 water-tight 

 compartments, while the hull proper is di- 

 vided by 17 bulkheads into 19 water-tight 

 compartments, each compartment having sep- 

 arate outlets to the promenade decks. Her 

 17 pumps are said to be capable of discharg- 

 ing 9,360 tons of water per hour. The con- 

 struction of the stern is very similar to that 

 of Kaiser Wilhelm der Grosse, excepting that 

 the plating below the water line, inclosing the 

 screw shafts, and above the rudder is cigar- 

 shaped, leaving a large arched space on each 

 side between the center line and screw shafts, 

 running forward and gTadually tapering for a 

 distance of about 25 feet into the common 

 hull shape. This has been done in accord- 

 ance with the requirements of the German 

 Admiralty, at whose disposal the ship will be 

 placed in the event of war. 



There are 4 sets of 4-cylinder expansion 

 vertical engines, with surface condensers, each 

 set working on 3 cranks, 2 sets for each pro- 

 peller shaft. The engines are balanced after 

 Mr. Schliek's patent and will indicate alto- 

 gether 38,000 to 40,000 horse-power. They are 

 set up in pairs, one behind the other, so as to 

 bring a water-tight bulkhead between each 

 pair, thereby increasing the safety of the 

 vessel. The steam will be produced by 12 

 double-end and 7 single-end boilers, which will 



Boat. 



Arrow .... 



Viper 



Turbinia . . 



Takou 



Taku 



Ellide 



Bailey .... 

 Murakumo 



Type. 



Yacht 



English Torpedo Destroyer . . 



Yacht 



French Torpedo Destroyer . . 

 German Torpedo Destroyer. 



Yacht 



U. S. Torpedo Destroyer . . . . 

 Japanese Torpedo Destroyer 



Knot. 



MilesperHour. 



Knots per Hour. 



1:32 

 1:38 

 1:44 

 1:52 

 1:52 

 1:55 

 2:00 

 2:00 



