160 RECORD OF SCIENCE FOR 1887 AND 1888. 



ill which are to be foiiin.1 the nocturnal aud diuraal radiations, not only 

 from the moon towards the earth, but from the soil of the earth towards 

 .space. {Nature.) 



Total eclipse of the sun, August 19, 1887. — Unusual preparations were 

 made throughout Europe for observing this eclipse, and great popular 

 interest was manifested in the event, but, unfortunately, very few ob- 

 servations of value were obtained on account of the generally cloudy 

 weather that prevailed over the whole region west of the Ural moun- 

 tains. The central line of the eclipse first struck the earth at a point 

 53 miles west-northwest of Leipsic, where the sun was just rising. The 

 Hue of totality, which was about 135 miles wide, then crossed Germany, 

 Russia, Siberia, China and Japan, and left the earth at a jjoint in the 

 Pacific Ocean in latitude 24^ 27' north, longitude 173^ 30' east. 



Eclipse of the moon, January 28, 1888.— The total eclipse of the moon 

 on January 28, 1888, presented an unusually fiivorable opportunity for 

 observing the occultations of a large number of faint stars, and, in 

 order to secure as many observations of these phenomena as possible, 

 Dr. DoUen, of Pulkowa, prepared and sent out to the principal observa- 

 tories in Europe and America, a list of the stars to be occulted at each. 

 He reports that he has received three hundred and ninety-six observa- 

 tions of disappearances and three hundred and eighty-seven of re-ap- 

 pearances, the places of observation being so favorably situated, that 

 he considers that there is ample material for determining the position, 

 the diameter, and possibly the ellipticity and parallax of the moon. 



SOLAR PARALLAX AND THE TRANSITS OP VENUS. 



Professor Harkness, at the meeting of the American Association in 

 Cleveland on August 20, 1888, gave a description of the instruments 

 and reduction processes employed by the United States Transit of 

 Venus Commission in determining the solar parallax from the measure- 

 ment of photographs taken at the ten American stations in December, 

 1882; Washington, Cedar Keys, San Antonio, Cerro Eoblero, Prince- 

 ton, and the Lick Observatory, in the United States; Santa Cruz and 

 Santiago, South America; AVellington, South Africa, and Auckland, 

 New Zealand. The preliminary value of the parallax deduced from the 

 measured distances of the centres of the sun and of Venus on 1,475 

 photographs is :r=S".847±0".012. The American photographs in 1874 

 gave 7:=8".883± 0".034, and the French r=8".80. The distance of the 

 sun corresponding to the value now obtained — 8". 847 — is 92,385,000 

 miles, with a probable error of only 125,000 miles. These numbers are 

 doubtless close approximations to the results which will be obtained 

 from the complete discussion of all the photographs, but they cannot 

 be regarded as final for several reasons, chief among which is the fact 

 that the reduction of the position angles of Venus relatively to the 

 sun's center is etill unfinished. 



The rex)ort of the committee ai)pointed to superintend the arrange- 



