Le soleil: exposé des principales découvertes modernes sur la structure de cet astre, son influence dans l’univers et ses relations avec les autres corps célestes. 2. éd., revue et augmentée.
Paris, Gauthier-Villars, 1875-1877
3 v., ill.; 250 mm
P.1, Texte. – 1875. – xx, 428 p.
P.1, Atlas. – 1875. – 6 folded plates
P.2. – 1877. – viii, 484 p.,  plates
INAF-Palermo Astronomical Observatory, Historical Library
This text is one of the most important 19th century treatises on the sun. Angelo Secchi were presents the results of his contemporary studies which contributed to deepen the knowledge of the chemical-physical nature of the sun. The first edition of Le Soleil was published in 1870 and became so successful that the volume was enlarged, revisioned and published again, in several editions and translations.
The volume on show is the second edition of the book, in which are included Secchi’s studies on the Sun carried out after 1870, which were initially published in Memorie della Società degli Spettroscopisti, the journal edited in Palermo by Pietro Tacchini, starting from 1872.
Volume I is open on the pages explaining the Wilson effect (sunsposts are represented as cavities); volume II is open on the plate illustrating the first three types of the classification of star spectra proposed by Secchi.
The volumes are accompanied by an atlas of solar spectrum lines, open on the page reporting the atlas of Sun spectrum lines made by Anders Jonas Angström in 1868, where it also appears a handwritten annotation by Tacchini, likely emission lines in the Sun, in correspondence with some manganese lines on table VI. [i.c., d.r.]
Bibl.: Chinnici 2014, pp. 80-82; Chinnici 2009, p. 201.