ASTRONOMY FOR 1889, 1890. 159 



Australia, and iu Tasmania, and in New Zealand, it was visible as a par- 

 tial eclipse. No observation of special interest was reported. 



Mr. J. M. Scbaeberle bas publisbed in tbe Monthly Notices a tbeory 

 of the solar corona, in wbicb be concludes tbat tbe corona is due to 

 tbe ligbt emitted and reflected by tbe filaments of matter tbrown out 

 by tbe sun, tbe corresponding' forces being variable and witb a period 

 about tbe same as tbe sun-spot period. The rays of double curvature 

 are explained by tbe rotation of tbe sun, and tbe apparent changes in 

 tbe general form of the corona by the position of tbe observer witb 

 reference to the plane of the sun's equator. 



Tbe Smithsonian Institution publisbed in 1889 a series of re produc 

 tions of a number of photographs of the eclipse of January 1, 1889, sent 

 from various stations on tbe Pacific coast. The pbotograi)bs are for 

 convenience of cotnparison reduced to a uniform scale of about 1 inch 

 diameter. Explanatory notes and remarlcs suggested by a study of the 

 ]diotograpbs are added by Prof. David P. Todd. 



Mr. H. H. Turner in tbe Philosophical Transactions (vol. 180, p. 385- 

 393) discusses tbe observations of tbe eclipse of August 29, 1886, made 

 at tbe island of Grenada. 



SOLAR PARALLAX AND THE TRANSITS OF VENUS. 



Transits of Venus in 1761 and 1769. — A thorough, and probably the 

 final, re-reduction of tbe observations of the transits of Venus in 

 1761 and 1769 has been made by Professor Newcomb in volume 2, part 

 5, of tbe astronomical papers of the American Ephemeris, a primary ob- 

 ject being the determination of the position of the node of Venus. The 

 value obtained for the solar parallax is 8". 79 with a probable error of 

 + 0".034. 



Professor Harkness of tbe U. S. Naval Observatory has devoted sev- 

 eral years of work to an elaborate discussion of the solar parallax and 

 its related constants. His principal results are elsewhere referred to, 

 the definitive value for the solar parallax being 8".80905 ± 0". 00567. 



The French ])hotograpbs of the transit of Venus give for tbe solar 

 parallax the value 8". 80 ± 0".06. 



OBSERVATORIES. 



Information in regard to the work going on at astronomical observa- 

 tories has been derived from the reports contained iu the Vierteljahrs- 

 sckn/t, in the Monthly Nofiecs, and in Loewy's Observatoires astro- 

 nomiques de Provence, and also from the separate reports publisbed 

 by a few observatories. The com^iiler is indebted in some instances to 

 directors of observatories who have communicated to him directly data 

 in relation to the institutions under their charge. When it has seemed 

 necessary to mak(^ a distinction, the year has been added to the note. 



AlleCtHENV: Langlcy. — Work ui)()n radiant energy has been con- 

 tinued, and the time service has been maintained as iu previous years, 



