FRAGMENTS OF SCIENCE. 



427 



gree, and it bears these features through the 

 entire course to the Gulf. The large tributaries 

 farther south modify but can not control their 

 overwhelming influence. The two periods 

 of flood characteristic of each of these large 

 tributaries have an important bearing upon 

 the continuance of high water in the main 

 river, pouring their floods in one after the 

 other as the force of the preceding flood is 

 beginning to be spent, so that the tendency 

 is for the main river to flow in strong volume 

 until well into the summer. The river is a 

 result ; its tributaries are the cause. Viewed 

 broadly, a general similarity of behavior is 

 observed ; yet each feeder of the main river 

 has its special cycle of alternations between 

 high and low water; each great line of 

 drainage has its special feature of flow. 

 Were the secondary watercourses followed, 

 the vast Mississippi water shed would be seen 

 covered by countless brooks and rivulets, 

 each affected by local conditions, yet all 

 obeying a few fundamental laws, "which 

 gather the waters as in the hollow of the 

 hand and pour them through a single chan- 

 nel to the sea." 



The Turbinia. In a recent issue of 

 Industries and Iron is a detailed description 

 of the Turbinia, the vessel which recently 

 attained the highest velocity ever reached by 

 a steam vessel, an average of 32f knots on 

 the measured mile. As her name suggests, 

 she is fitted with steam turbines instead of 

 the ordinary form of engine. The Turbinia 

 was built by a syndicate formed especially 

 for the purpose of testing the application of 

 the compound steam turbine to marine pro- 

 pulsion. She is 100 feet in length, 9 feet 

 beam, and 44 tons displacement. The 

 original turbine fitted in her was designed to 

 develop upward of 1,600 actual horse power 

 at a speed of 2,500 revolutions per minute. 

 The boiler is of the water- tube type, for 225 

 pounds per square inch working pressure. 

 The hull is built of steel plates, varying in 

 thickness from -fe to ^ of an inch. A 

 curious difficulty was encountered in the 

 early trials. It was noticed that a great deal 

 of power was being lost somewhere, and it 

 finally turned out that, owing to the high 

 speed of the propeller, what is known as 

 cavitation was produced that is, the screw 

 tended to scoop out a hole in the water and 



run in this, thus using up a part of the ener- 

 gy simply in maintaining this cavity. This 

 difficulty has been, to some extent, overcome 

 by altering the pitch of the blades, but it is 

 believed that further experimentation will 

 result in overcoming this fault more com- 

 pletely, and hence make a still higher rate of 

 speed possible. 



German Colonies for Unemployed Work- 

 men. The first of the German Arbeiter 

 Kolonie, or refuges for workmen out of em- 

 ployment, one of which has been described 

 in the Atlantic Monthly by Mr. Josiah Flynt, 

 was established by Pastor von Bodelschwingh 

 at Bielefeld, Westphalia, about 1882. There 

 are now twenty- seven such colonies in Ger- 

 many, where men able and willing to work 

 may go, and at least pay their way till some 

 more profitable labor is found. Connected 

 with them is an estate near Berlin, where 

 men who have proved deserving may acquire 

 a piece of land and eventually set up homes 

 of their own. Applicants for help must 

 promise to stay in the colony at least four 

 weeks, and have the privilege of staying 

 longer if no work has been found for them 

 outside ; while the managers are on the look- 

 out for work for them, in order that they 

 may go and other out-of-works may take 

 their place. The colonies are supported by 

 contributions and the proceeds of the work 

 of the colonists. Mr. Flynt applied at the 

 Berlin colony at Tegel, and, on complying 

 with the conditions required, was assigned 

 to a section and set to making straw cases 

 for wine bottles. He was expected to work 

 to the best of his ability and to show respect 

 to the officials a Hausvater and a fore- 

 man, the only outsiders connected with the 

 institution. The day was spent according 

 to a prescribed routine, beginning at five 

 o'clock in the morning and ending at nine 

 o'clock at night, while Sunday was given to 

 church and rest. Every man received a 

 mark, or twenty-five cents, a day, and some, 

 working by the piece or at special work, 

 made a mark and a half. Out of these 

 earnings, eighteen cents a day were taken 

 for food and lodging. Several men had 

 credit in the colony treasury. The food was 

 simple but abundant, and the beds were 

 fairly comfortable. A store was opened on 

 Saturday afternoons, where the colonists 



