164 



Scientific Intelligence. — Natural History. 



Analysis of an ore of platina from Barbacoas in the province of 

 Antioquia de la Columbia. 



This ore consists of grains which often weigh more than a drachm, 

 intermingled with those which are smaller. The largest grains I 

 found to be composed as follows : — 



2. On the Silicate of Iron, of Badenmais, by Prof. Kobell, of 

 Munich. (Annalen de Physik.) — This mineral, reduced to very 

 fine powder, is attacked by hydro-chloric acid. 

 20 parts gave the following results : — 



Silica, 



Protoxide of iron. 



Sulphur, ..... 



Water, 



6.12 



10.32 



.18 



3.74 



20.36 



As it is found with pyrites, the sulphur doubtless arises from a 

 slight mixture of these latter. In making the needful deduction and 

 attending to the increase of weight, we have — 



Silica, . . . 31.18 — containing oxygen, 16.25 

 Peroxide of iron, . 50.86 15.59 



Water, . . 19.12 16.99 



101.26 

 This mineral may therefore be regarded as a silicate of hydrate 

 of iron. — Idem. 



3. On a new mineral, Hydro-carhon. — A combustible substance 

 has been found by Colonel Scherer in the interstices of lignite or 



