422 



SCIENCE. 



[N. S. Vol. IX. No. 220. 



way to the coast by the river route. With a 

 few Chinese companions he has travelled 

 through the greater portion of Thibet and made 

 a trip from the Siberian line to Toug King. 



Steps have been taken by the British gov- 

 ernment to guard against undue destruction 

 of wild animals In Africa, by the issue of game 

 regulations. The German government has 

 been consulted, and it is proposed to hold an in- 

 ternational conference on the subject in London 

 in the spring. 



The New York Post-Graduate Hospital has 

 received $100,000 from Mr. Harris Fahenstock 

 for a training school for nurses. 



Professor R. W. Wood, of the University of 

 Wisconsin, has discovered a new method of pho- 

 tographing in natural colors. He reproduces 

 the colors by diffraction, and, though at present 

 the production of the first finished picture is 

 somewhat tedious, duplicates can be printed as 

 easily as ordinary photographs are made The 

 pictures are on glass, and are not only color- 

 less, but almost invisible when viewed in ordi- 

 nary lights, but when placed in a viewing 

 apparatus, consisting of a convex lens on a light 

 frame, show the colors of nature with great brill- 

 iancy. The principle is that the picture and 

 the lens form spectra which overlap and the 

 eye placed in the overlapping portion sees the 

 different portions of the picture in color depend- 

 ing on the distance between the grating lines at 

 that place. Professor Wood says the finished 

 picture is a transparent film of gelatine with 

 very fine lines on it, about 2,000 to the inch 

 on the average. The colors depend solely 

 on the spacing between the lines, and are 

 pure spectrum colors, or mixtures of such, the 

 necessity of colored screens or pigments, used 

 in all other processes except that of Lippman, 

 having been overcome. The pictures cau be 

 projected on a screen by employing a suitable 

 lantern, or can be viewed individually with a 

 very simple piece of apparatus consisting of a 

 lens and perforated screen mounted on a frame. 

 A peculiarity of the process is that there is no 

 such thing as a negative in it. Half-a-dozen pic- 

 tures have been printed in succession, one from 

 another, and all are positive and indistinguish- 

 able from each other. 



The record for kite-flying for scientific pur- 

 poses has again been broken at the Blue Hill 

 Observatory ; 12,440 feet above the sea-level 

 was reached on February 28th by a recording 

 instrument attached to a string of tandem kites. 

 This is 366 feet higher than the preceding best 

 record, made at the same place on August 26th. 

 The flight was begun at 3:40 p. m., Tuesday, 

 the temperature at the surface being 40° and 

 the wind seventeen miles an hour. At the high- 

 est degree the temperature was 12° and the 

 wind velocity fifty miles an hour. Steel wire 

 was used as a flying line, and the kites, four in 

 number, were of an improved Hargreave pat- 

 tern, with curved surfaces, made after the pat- 

 tern of soaring birds' wings. The upper kite 

 carried an aluminum instrument weighing four 

 pounds, which recorded graphically tempera- 

 ture, wind velocity, humidity and atmospheric 

 pressure. The combined kites had an area of 

 205 square feet and weighed twenty-six pounds, 

 while the weight of the wire was seventy-six 

 pounds. The upper kite remained above two 

 miles for about three hours, and was reeled in 

 by a steam windlass, constructed for that pur- 

 pose. When within half a mile of the ground 

 the fastening on one of the kites slipped, and 

 this carried it up to the one above, the added 

 pull snapping the wire and sending three kites 

 adrift. A search for the lost kites was begun on 

 Wednesday, and two of them were found at the 

 Milton town farm, about two miles away, 

 but the third was not recovered until later, 

 when it was found at Field's Corner, over six 

 miles north of the Observatory, or more than 

 half the distance between that point and the 

 State House. The recording instrument was 

 found uninjured. This was the last of a series 

 of five high flights made on successive days, 

 Sunday excepted. The average height reached 

 was 10,300 feet, or nearly two miles. The 

 temperature at 10,000 feet on February 23d was 

 5° ; on the 24th, 1° ; on the 25th, 11°, and on 

 the 28th, 20° above zero. 



The British Iron Trade Journal attributes the 

 remarkable expansion of the iron and steel in- 

 dustries of the United States to the following 

 favorable changes in economic conditions : (a) 

 'Intensive' production, reducing costs gener- 

 ally; (6) Reduced costs of ores and develop- 



