Till-: M\\A\\ WAY. 



r.v Ri;v. T. i:. ESPIN. .M.A., F.K.A.S. 



In tliL- years from Iti'Jl to 1893 ii valuable series of 

 papers were published in " KnoWLicdci: " b\- M. 

 Kanyard. some being contributions of liis own. on 

 "The Structure of the Milky Way," 

 others by Messrs. Maunder. \\'esle\- 

 and Sutton : while letters appeared 

 from Professor Barnard and 

 others. The articles were illus- 

 trated by photographs of "The 

 Milky Way," taken by Professor 

 Max \\'olf. Professor Barnard, and 

 in the South by Mr. Kussel. The 

 general result seemed to be that 

 the theories of the past — such as 

 may be summed up as the Cloven 

 Disc theory of \\'right, Herschel, 

 Struve, the Spiral Theory of 

 Proctor, or the Double King 

 Theory — all failed to explain the 

 phenomena presented by the 

 photographs. 



TwentN' years have now passed, 

 and during that time many fresh 

 pliott>graphs, with various aper- 

 tures, have been obtained. 

 Professor Wolf has published a 

 complete series of the Milky Wdx, 

 as visible at Heidelberg, made with 

 angled lens, in " Die Milchstrasse,' 



and at the Harvard Station of Arcquipa. The 

 piioto-telescopes of eight-inch and twenty-four- 



incli npiTtnr.-. tift.-.| vvit), ol.jrrtive iirisms. have 



small wide- 

 and a great 



Fir.l'KK 33. Cy.sinus. 



mass of fresh material 'has accumulated from 

 the photographic researches at Harvard College, 



Figure 32. Aquila. 



been diligently used, and the examinations of 

 the plates by the late Mrs. Fleming have 

 revealed the fact that certain 

 classes of heavenly bodies are 

 found almost without exception 

 in or near the Milky Way. 

 The stars of Tj-pe \', the Gaseous 

 Nebulae, the Orion stars with 

 bright lines, the Temporary stars, 

 all tend to arrange themselves in 

 positions of small Galactic lati- 

 tude. On the other hand, as is 

 well known, "white" nebulae and 

 globular clusters avoid the Milk}- 

 Way. The stars of Type \' show , 

 above all others, not only an 

 affinity for the Galaxy, but for the 

 apparent centre of it. In 1891 

 our knowledge of the stars of 

 Type V was extremely meagre ; 

 there were the original Wolf- 

 Rayet stars in a group in C)gnus; 

 subsequently others were swept 

 up with the spectroscope by 

 Copeland and Pickering. An 

 examination of the photographic 

 plates taken at Harvard and Arequipa have re- 

 vealed a large number of new ones, and it seems 



