LIST OF PLATES. 



Secretary's Report: Page. 



Plate I. Elephant house and yard 66 



II. Echidna, Tasmanian devil, and zebra wolf 66 



III. Stirring tube for coelostat 76 



IV. The large coelostat with second mirror, Smithsonian xVstrophys- 



ical Observatory 78 



V. Bolographic energy curves of the solar spectrum of a 60° glass 



prism. Observations of April 17, 1903 78 



VI. Transparency of the atmosphere from bolographic oljservations. . 80 

 VII. Distribution of radiation in the normal solar si>ectrum outside 



the earth's atmosphere 80 



The Moon (Shaler). (Explanation page faces each plate): 



Plate I. Moon's age, 8 days, 4 hours 114 



II. Moon's age, 10 days, 12 hours 1 14 



III. Moon's age, 14 days, 1 hour 114 



IV. Moon's age, 23 days, 7 hours 114 



V. Moon's age, 21 days, 16 hours 114 



VI. Photograph by Ritchey 114 



VII. Copernicus and Kepler 114 



VIII. Eay system about Tycho 114 



IX. Mare Nubium and surroundings 114 



X. Mare Tranquilitatis and surroundings 1 14 



Progress with Airships (Baden-Powell): 



Plate I. The Lebaudy airship 168 



II. Car of Lebaudy airshij) 168 



III. Lebaudy airship inside the shed 170 



IV. (o) Lebaudy airship, view from below; {h) the Lebaudy shed. . . 170 

 Tetraiiedral Kites: 



Plate I. Fig. 1, Winged tetrahedral cell. Fig. 2, Sixty-four-cell tetrahedral 



kite. Fig. 3, Four-celled kite. Fig. 4, The Aerodrome kite... 184 

 "N" Rays (Abbot): 



Plate I. Increased luminosity produced by " N " rays 210 



High Speed Electric Railways (Gibson): 



Plate I. Types of modern American cars for heavy electric-railway service. 316 

 II. Fig. 1, Locomotive for the Buffalo and Lockport Railway. 

 Fig. 2, Map showing development of electric railways about 



Cleveland, Ohio 316 



III. Interiors of advanced type trolley cars 320 



IV. DusSeldorf-Krefeld road, with cars which run at 60 km. per hour. 320 



V. Fig. 1, Suspended railway and train at Elberfeld. Fig. 2, Truck 



of the Gornergrat locomotive. Fig. 3, Stansstad-Engelberg 



electric locomotive before housing 322 



i.v 



