132 



NATURE 



\7une%, 1876 



glowing-fire, or intense heat of the surface; and (7) the 

 Kiinstliche Feuer of Gruithuisen. 



There is one characteristic of the phenomenon abun- 

 dantly verified by the numerous observers who have 

 recorded it, which cannot be overlooked in our endeavours 

 to arrive at its true cause, viz., its intermittent or only 

 occasional visibility. This alone appears to render more 

 than one of the explanations which have been advanced 

 highly improbable if not wholly inadmissible. There are 

 also isolated observations which seem rather to favour 

 one or other of the hypotheses. Thus Schroter con- 

 sidered that the change in the colour of the faintly illu- 

 minated disc from reddish to ashy-grey remarked by 

 Harding, indicated a connection with our aurora borealis, 

 in exhibitions of which similar rapid changes or alterna- 

 tions of colour are observed, and a very curious observa- 

 tion by Madler has been cited in the same direction. On 

 April 7, 1833, at 8 P.M., in a sky of extraordinary clear- 

 ness and tranquillity, Venus, then in crescent-phase, 

 appeared to him accompanied by a beautiful radiating 

 appearance ; seven or eight straight rays, at times very 

 bright and sharply defined, at others fainter and more 

 diffused, occupied the north-west quadrant, and were 

 gradually lost in the general ground of the sky. The 

 longest ray extended about 1 5', the shortest was about half 

 that length ; neither turning round the eye-piece, nor 

 viewing the planet in different parts of the field of the 

 telescope, at all affected the phenomenon, which continued 

 unchanged as long as Venus was observed that evening. 

 A figure of this appearance is attached to Madler's 

 account of his observation. 



Zollner has expressed his conviction that under spectro- 

 scopic examination, the ash-coloured secondary light of 

 Venus will be found to present bright lines, and it may be 

 hoped that opportunities for such observations may occur 

 during the present summer. 



By closely watching the form of the crescent towards the 

 extremities, further evidence of rotation in rather less time 

 than is occupied by the earth in her diurnal revolution, 

 may also be obtained. But with this object, observations 

 must be made at very short intervals. In illustration 

 of this may be quoted Madler's experiences on June 6 

 and 10, 1836. 

 h. 



June 6, 10 41 Sid. T. 



June 10, 



10 

 36 



38 



56 

 14 

 26 



38 



Both horns equally pointed, and the 

 curvature quite elliptical. 



The same. 



The northern horn appears to be the 

 more pointed. 



The northern horn certainly more 

 pointed : also at iih. 43m. 



Again uncertain. 



Both horns ahke. 



The northern is more pointed. 



Again doubtful. 



Madler referring to these and other observations of a 

 similar character, in May and June 1836, expresses his 

 opinion that they are quite irreconcilable with Bianchini's 

 period of rotation, but may be compatible with the shorter 

 one of Cassini and Schroter. 



The Minor Planets. — The following summary is 

 founded upon elements of 153 members of this group, 

 which appear to be sufficiently well determined to afford 

 reliable results. It exhibits the distribution of the peri- 

 helia, nodes, inclinations, and excentricities, and will be 

 seen to offer several very decided characteristics. 

 I. Longitudes of the Perihelia. 



A FREE SPANISH UNIVERSITY 



OUR readers will easily understand what sort of a 

 foster-mother a 'Government like that of Spain will 

 prove to education generally, and to scientific education 

 and inquiry in particular. Any educational institution 

 connected with such a state must necessarily be ham- 

 pered and hindered in many ways, and the only chance 

 of obtaining perfect liberty in scientific education and 

 instruction is in being rid of all state interference. 

 This has been so strongly felt in Spain by some of 

 the foremost Spanish men of science and letters that 

 they have formed an association to found an institu- 

 tion for free education. A prospectus of the institution 

 has been forwarded us, and the difficulties which beset 

 a liberal education in Spain may be learned from the fact 

 that it is signed by ten ex-professors of the highest 

 standing, all of whom have been removed from their 

 chairs by Government on account of their liberal opinions. 

 Among these are the names of Augusto G. de Linares, 

 ex-Professor of Natural History at the University of 

 Santiago, and Laureano Calderon, ex-Professor of Organ'c 

 Chemistry at the same University. The object of the 

 Association, as stated in the prospectus, is to found at 

 Madrid a free institution dedicated to the culture and 

 propagation of science in its various branches, specially 

 by means of education. A sort of joint-stock company 

 will be constituted by shares of 250 francs, payable in 

 four instalments between July next and April 1877. A 

 preliminary meeting was to be held on the ist inst, to 

 constitute the Society, and we earnestly hope that a suc- 

 cessful start has been made. The Association will be 

 directed by a Council representing all parties interested. 

 The Institution itself will, of course, be perfectly free from 

 all religious, philosophical, or political restrictions, its 

 only principles being the "inviolability of science" and the 

 perfect liberty of teaching. There will be established, 

 according to the circumstances and means of the Society 

 (i) studies for general, secondary, and professional edu- 

 cation with the academic advantages accorded by the laws 

 of the State ; (2) superior scientific studies ; (3) lectures and 

 brief courses, both scientific and popular ; (4) competi- 

 tions, prizes, publication of books and reviews, &c. The 

 greatest precautions will be taken to obtain as professors 

 men of undoubted probity and earnestness and of the 

 highest competence. 



We need say nothing to our readers in recommenda- 

 tion of the above scheme. All who sincerely desire the 

 welfare of Spain and the spread of scientific knowledge 

 must sympathise with its promoters, who, we have every 

 reason to believe, are men of the highest character and 

 competency. We hope that not a (ew of our readers will 

 show their sympathy with the object of the Association 

 by sending the moderate subscription which constitutes a 

 shareholder to M. Laureano Figuerola, Calle de AlcaM, 

 72, Madrid. 



