Scientific Intelligence. 439 



Orsay, and In that of the quarry of Seaux-les-Chartreux, near Palaiseau. 

 In the " Geognosic du Bassin do Paris/' published by Brongniart and Cu- 

 vier in 1822, mention is made of the occurrence of deposits of arenaceous 

 limonite and scattered nodules of hydrate of iron^ in the same position as 

 the cobalt has now been found; and in 1835, M. Brongniart observed in 

 the sand accompanying the millstones of the quarry of Tarteret a thin bed 

 of red argillaceous sand, which, from its external characters, he suspected 

 to contain manganese ; and this idea was confirmed by the analysis made 

 by M. Malagutti. In the deposits of marly gypsum near Paris, mangan- 

 ese has been found in concretions, and having a dendritic arrangement ; 

 and zinc has been detected in the arenaceous limestones which form the 

 transition from the gypsum formation to the calcaire grossier. Besides 

 iron, manganese, and zinc, no other metal has hitherto been discovered in 

 the tertiary series ; but the discovery now announced proves that cobalt, 

 a metal formerly regarded as one of the most ancient, whose presence 

 had not been detected even in the chalk or Jura formations, either in 

 veins or disseminated portions, exists disseminated, and in an original pO" 

 sition, in the upper sandstone of Paris, that is, in the middle tertiary for- 

 mation. In the present case the cobalt is accompanied by the substances 

 generally associated with it, copper and arsenic, but also by manganese, 

 which has never been found combined with it except in one instance. 

 The only other authentic example of manganesian cobalt, being one men- 

 tioned by the Duke of Luynes himself, as occurring at Rengensdorf, in 

 Alsace, at which locality a compound is found having great analogy to 

 that of Orsay, but in a very dificrent geological position, viz. in a vein of 

 quartz traversing clay-slate. M. Brongniart remarks, that, if we carry out 

 researches further, and examine what are the metals which have been 

 brought to the surface of the earth during or after the tertiary period by 

 volcanic action, we find thai in lavas, basalts, trachytes, &c. there occur 

 disseminated, iron, manganese, titanium, and copper, but no cobalt ; and 

 in veins, lead, zinc, antimony^ silver, gold, and tellurium, but still no co- 

 balt. Among the products of volcanos at present in action we find fre- 

 quently arsenicj selenium, copper, and iron ; but the only indication of 

 cobalt hitherto discovered, was in a salt of cobalt observed by Davy in 

 one instance in Vesuvius. M. Brongniart terminated his communication 

 to the Academy by stating his belief that geologists, by careful investiga- 

 tion, will succeed in detecting manganese, cobalt, and zinc in other loca- 

 lities of tertiary rocks, for these metals " must have been introduced into 

 the tertiary strata of Paris by powerful and, consequently, general causes, 

 and there is no example on the face of the globe of a phenomenon limited 

 to one single point." 



7. On the Colours of Flowers. — A curious essay on this subject, entitled 

 " Die/arben der Bl»tlien" was published last year at Bonn, by Dr Mac- 

 quart, from which we extract the following abstract of the results ob- 

 tained : — 1. All flower leaves are originally green in the bud. 2. Chloro- 

 phyll contains no nitrogen. 3. All the tints of flowers are produced by 



