718 PK0UKE8S OF ASTRONOMY FOR 1891 AND 1892. 



ada Pailiaiueut has decluivd as legal the uoriiial hours from Green- 

 wich adoDted since 1883 by railways and later by a great number of 

 towns. lu England a commission iias reported favorably upon the 

 system of hourly meridians, and the (rovernment has strongly recom- 

 mended it to the colonies. In France, Paris mean time is used for all 

 the country, including ^Vlgeria. In r>elgium a commission has recom 

 mended the hourly meridian system, with (rreenwich as the starting 

 point. In Holland the Ooveriiment has authorized the adoption of 

 Greenwich time for interior railway service. In Prussia mean Euro 

 pean time (mitteleuroi);iisclie Zcit or ^I. K. Z.) which is one hour greater 

 than Greenwich time, replaced Berlin time from the 1st of June, 1801, 

 for the railway service of the interior. l>avaria, W'iirtemberg, and 

 Baden have also decided on M. E. Z., which will also be used in Al- 

 sace-Lorraine. Austria and Hungai> ado]>ted M. K. Z. from October 

 1, 1891, for lailway, i)OSt, and telegraph service, and there is a strong 

 feeling for its adoption in civil life. In Italy, at the instance of the 

 Academy of Sciences of Bologna, which favors the meridian of-leru- 

 salem, there was a i^lan for assembling a new congress at Rome, but this 

 however, seems to have been abandoned. There is here as well as in 

 Switzerland a strong sentiment in favor of Greenwich as the standard. 



At the Cape of Good IIo]»e the extension of railways brought about 

 the adoi)tion of a single-standaid time throughout the colony in Feb- 

 ruary, 181)1*. Ihc meridia.n one an<l one-half hours east of Greenwich 

 is in use for all i»uri)oses hi Cape Colony and the Orange Free State, 

 and all time signals arc given at Greenwich noon. 



tSki/ </l(ii('s. — The after-glows that attracted so much attention in \Sf>3 

 and 1884 showed some signs of return, though in lesser degree, in the 

 early ])art of 1891. The tint and g<'neral appearance arc reported to 

 have greatly resembled the auroral displays. 



The systematic study of these "luminous night clouds" has been 

 taken up by Prof. Foerster and Herr Jesse, of the Berlin observatory. 



The Moon. — A valuable contribution has been made to the study 

 of the moon in "An essay on the distribution of the moon's heat and 

 its variation with the phase,'' by Mr. F.W. Very, of the Allegheny Ob- 

 servatory — a paper Avhich gained the iirize proposed in July, 1890, by 

 the Utrecht Society of Arts and Sciences. Mr. Very's investigation 

 was made with one of Langley's " bolometers," and the principal results 

 may best be described in the author's own words : 



First, that visible rays form a much larger proportion of the total 

 radiation at the full than at the partial phases, the nmximuni for light 

 Ix'ing much more ])ronounced than that fo" the heat. Next, as has 

 been foreseen from the eccentricity of the heat areas, their greater ex- 

 tension toward the western lind), and the greater steepness of the sun- 

 set than of the sunrise gradient, the diminution of the heat from the 

 full to the third (juarter is slower than its increase from the tirst (juarter 

 to the bill. Finally, there <>; a fair agreement between these results and 

 those of Lord IIonsc, which extends even to some minor details, such 

 as the attainmeiic of the hiiiuest heat at little* before the full. 



