8 



SCIENCE 



[N. S. Vol. LII. No. 1331 



Barnes — and to go on at length, but where 

 couid I end it ? Besides, it is not my func- 

 tion to deploy the Golden Age of the acad- 

 emy, but merely its founding. The other 

 source of change camie even closer to the 

 hearts of the founders, the coming of choice 

 youth of the state into productive member- 

 ship in the academy, the children of the 

 academy. They were equally and perhaps 

 more the children of the educational insti- 

 tu:tions of the state, but we claim them as 

 children of the academy none the less. 

 Very nota;ble among these was President 

 Van Hise, who rapidly rose to leadership 

 in the state, in the nation and beyond. It 

 would be a delight to name many others, 

 but how could the parental affection of a 

 founder permit him to stop short of naming 

 all the children of the academy? The di- 

 lemma is in itself evidence that the forma- 

 tive stage of the academy had already 

 passed away. The founding of the academy 

 had really taken place. 



Thomas Chrow^der Chamberlin 

 Univebsitt of Chicago 



SCIENTIFIC EVENTS 



AITOFF'S EQUAL-AREA PROJECTION OF THE 

 SPHERE 



A PROJECTION of the whole sphere on an 

 equivalent or equal area system devised by 



Aitoff, has just been issued by the TJ. S. 

 Coast and Geodetic Survey, size 11 inches, 

 price, 15 cents. 



The sphere is represented within an ellipse 

 with major axis twice the minor axis. 'No 

 shoreline has been included since it is in- 

 tended primarily for the plotting of the stars 

 in astronomical work, its value for this kind 

 of work being suggested by Professor Ben- 

 jamin Boss, of the Dudley Observatory, 

 Albany, N. Y. 



The projection is bounded by an ellipse 

 similar to that which is used in MoUweide's 

 equal area projection but, since the parallels 

 are curved lines, the distortion in the polar 

 regions is less in evidence. The net-work of 

 meridians and parallels is obtained by the 

 orthogonal or perpendicular projection of a 

 Lambert meridional equal area hemisphere 

 upon a plane making an angle of 60" to the 

 plane of the original. 



The fact that it is an equivalent or equal 

 area projection combined with the fact that 

 the celestial sphere is represented in one 

 continuous map, will show at a glance the 

 relative frequency of stars in the different 

 regions of the expanse of the heavens. As 

 constructed the radius of the sphere to be 

 projected is taken as a decimeter so that the 

 graticule has a very convenient size for gen- 

 eral use. 



As used for a map of the world, this pro- 

 jection is well adapted to replace the Mercator 



