4300 Corona and Chromosphere. 



4320 Chromosphere. General. 



Radial Extent. 



Form of Prominences and Changes in ditto. 

 Spectrum (see below, 4700). 

 Periodic Changes. 

 Photographs, Drawings. 

 4340 Moon on Corona, Baily's Beads, &c. 



4350 Terrestrial Pheuomena during Eclipses. 



4360 Photographs of Sun [i.e., references to published 



reproductions). 

 Drawings of Sun (ditto ditto.) 



Spectroscopy of Sun and Eclipses. 

 4500 Solar spectrum (integrated sunlight). General. 



4510 Ultra-violet spectrum. 



W^aveleugchs, Maps, Photographs. 

 4520 Visible spectrum. 



Visual, Photographic (Wavelengths, Maps, 

 Photographs). 

 4530 Ultra-red spectrun:. 



Photograjihic, Bolonietric (Wavelengths, 

 Maps, Photographs). 

 4540 Identification of lines with Elements. 



4550 Changes in appearance of lines (width, infeusitj'). 



4560 Bright lines. 



4570 Distribution of energy in spectrum. 



4580 Telluric lines. 



4600 Spectroscopic researches of surface without eclipse. 



4610 Spots. 



4620 Faculse. 



4630 Chromosphere without eclipse. 



4640 Determination of rotation. 



4650 Spectroscopic researches of Sun in eclipse. 



4660 Corona. 



47(10 Chromosphere. 



4750 Physical coustitutioM deduced fro.n Spectroscopic 



Observations. 

 4800 Moon. Generid. 

 4810 Observations for position. 



4820 Constants, Dimensiono (diameter and figure), mass, 



density, distance. 

 4830 Rotation (Libration see also 1730), ConfiguratioL of 



Surface, changes in ditto. 

 4840 Atmosphere. 



4850 Temi)erature, Padialicii, Ihightness, Phases. Lumieie 



Cendre'e. 

 48G0 Eclipses, {^ce aL^o 0350). 



4870 Occultation (stars, planets, separately). (See a/so 0350). 



4880 Intlueiice on Terrestrial pheuuiuena. (See also Tides 



and F 0480). 

 4890 Photographs, Maps, Diawinns (published repro- 



ductions). 



