16 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



THE SOLAR PARALLAX. 



At the April meeting of the Royal Astronomical Society, 

 Lord Lindsay, after giving a description of the form of in- 

 strument which he has devised for taking photographs during 

 the coming transit of Venus, read a paper on a method of 

 determining the solar parallax from observations to be made 

 at the next opposition of the asteroid Juno, which occurs in 

 November of this year. He proposes, while stationed in the 

 Mauritius for the purpose of observing the transit of Venus, 

 to take advantage of his position to make a series of helio- 

 metric measures of the distance of Juno from the nearest 

 fixed stars, and, by comparisons between the measures taken 

 soon after Juno has risen above the eastern horizon with 

 those taken before it sets at the western, to determine the 

 terrestrial parallax. By this method he will be able to make 

 his measures, during all the clear nights of the period, for six 

 weeks before and after the opposition of the planet; and, al- 

 though the parallax will be considerably less than in the case 

 of Venus, he considers he lias reason to hope that the prob- 

 able errors of the result will be less, owing to the number of 

 measurements, and the ease of dealing with points of light 

 instead of disks, than they are in the case of the transit of 

 Venus or the opposition of Mars. 12 A, 1873, IX., 475. 



THE NATURE OF THE SOLAR SPOTS. 



Professor Sporer, the well-known observer of the solar spots, 

 makes a comparison between the spots observed by himself 

 and the protuberances depicted by the Italian spectroscop- 

 ists Secchi and Tacchini, and shows in numerous examples 

 their agreement with conclusions which he developed in 1871 ; 

 namely, that the solar faculae occur on the same spots where 

 flame-like protuberances exist, or where the so-called flame 

 chromosphere occurs; and, again, that these protuberances 

 in most cases stand in such a connection with the dark spots 

 that the former are much more important before and at the 

 time of the origin of groups of spots than they are subse- 

 quently ; and, finally, there are many cases where the spots 

 are subsequently found in precisely the same region where 

 previously were notable flame-like protuberances. Indeed, 

 he adds, even before spectrum observations were instituted, it 



