November 11, 1921] 



SCIENCE 



457 



scale 1/5,000,000; dimensions 17 X 26J in., 

 price 25 cents. 



The map extends from the Arctic Ocean 

 in the north to the State of "Washington in 

 the south, and includes all of the Aleutian 

 Islands and a part of Eastern Siberia. It 

 is intended merely as a base map to which 

 may be added any kind of special informa- 

 tion that may be desired. For this reason 

 only national boundaries, the adjacent Cana- 

 dian provinces, and the names of a few of 

 the important towns are given. The shore- 

 line is compiled from the most recent Coast 

 and Geodetic Survey charts and in respect 

 to southeast Alaska and westward to Kodiak 

 Island, the coast-line is better represented 

 than heretofore. The accumulation of the 

 yearly surveys in the extensive and largely 

 unsurveyed waters of Alaska as here em- 

 bodied, presents a delineation of the coast- 

 line in a more really true shape than hereto- 

 fore and in this respect the map is more 

 reliable than other existing maps of similar 

 scale. 



In addition to this feature, the employ- 

 ment of a more suitable system of map pro- 

 jection adds to the general accuracy. On ac- 

 count of the predominating east and west 

 extent of Alaska, the Lambert conformal 

 conic projection with two standard parallels 

 offers advantages over other projections for- 

 merly used in mapping this region. This is 

 the system which came to prominent notice 

 during the World War and was employed by 

 the allied forces in their military operations 

 in France. 



The parallels employed as standards are 

 . the latitudes 55° and 65°, and along these 

 parallels the scale is true. Between these 

 parallels the scale becomes too small by less 

 than four-tenths of one per cent., which 

 amount is insignificant. At Dixon entrance 

 in southeast Alaska, the former general chart 

 of Alaska on a poly conic projection was in 

 error by as much as ten per cent, due to a 

 system of projection which was unsuited to 

 the shape of the area involved. In the new 

 base map, the projection error in this local- 

 ity is entirely eliminated. The miaximum er- 



ror of scale of the Lambert projection is only 

 1 3/4 per cent. This is in the latitude of 

 Pt. Barrow in the north where the scale is 

 too large by this amount. The same amount 

 of error appears in latitude 48° but this is 

 considerably south of Alaska, which ■ is the 

 subject of the map. The polyconic projec- 

 tion had the effect of exaggerating areas in 

 the most important part of Alaska whereas 

 in the Lambert projection the maximum scale 

 error is placed in the least important part 

 of Alaska, and in amount is only one sixth 

 as large as in the polyconic projection. 



For the measurement of distances and 

 areas within the extent of the map, an ac- 

 curacy is thus obtained that is well within 

 the limits of draftsmanship, paper distortion, 

 and our knowledge of this region as a whole. 



The selection of a suitable projection with 

 a conformal grid system of one degree units, 

 makes the new outline map a convenient base 

 for the addition of special and useful infor- 

 mation. The inclusion of the northwest 

 part of the state of Washington serves as a 

 connecting link with a similar Lambert con- 

 formal base map of the United States which 

 has already been published on the same scale. 



SCIENTIFIC EVENTS 



INVESTIGATIONS OF THE U. S. BUREAU OF 

 MINES ON OZONE AND VENTILATION 



The Pittsburgh Experiment Station of the 

 United States Bureau of Mines, according tc 

 a bulletin of the bureau, is working in co- 

 operation with the Eesearch Bureau of the 

 American Society of Heating and Ventila- 

 ting Engineers on a number of problems which 

 affect each individual in his home life, in his 

 place of business, and especially in those 

 places where many people congregate, as in 

 churches, school-rooms and theaters. It is im- 

 portant to ventilate such places with suiScient 

 fresh air to make every one comfortable 

 enough to be able to work at high efficiency. 

 The circulation of excessive quantities of 

 fresh air imposes a considerable cost on the 

 heating system, therefore an efficiently de- 

 signed heating and ventilating system intro- 

 duces the least amount of cooled air con- 



