PORTION OF THE COSMOS. AE110LITES. 445 



the whole of the mixture (as labradorite, hornblende, augite, 

 or oligoklas). 



" /3. The second, much rarer, class of meteoric stones has 

 been less examined. These stones sometimes contain mag- 

 netic iron, olivine, and some feldspatic and augitic sub- 

 stances ; and sometimes they consist merely of the two last 

 mentioned simple minerals, and the feldspar is then repre- 

 sented by anorthite ( 707 ). Chromate of iron (protoxide of 

 iron, oxide of chromium) is found in small quantities in 

 almost ell meteoric stones : phosphoric acid and titanic 

 acid, discovered by Eammelsberg in the remarkable stone of 

 Juvenas, may perhaps indicate the presence of apatite and 

 titanite. 



" The simple substances which have as yet been shewn to 

 exist in meteoric stones are the following : Oxygen, sul- 

 phur, phosphorus, carbon, silicon, aluminum, magnesium, 

 calcium, potassium, sodium, iron, nickel, cobalt, chrome, 

 manganese, copper, tin, and titanium ; being in all 18 sub- 

 stances ( 708 ). The more immediate components are 

 a, metallic : an alloy of nickel and iron, a compound of 

 phosphorus with iron and nickel, sulphide of iron, and 

 magnetic pyrites ; b, oxydised : magnetic iron and chro- 

 mate of iron j c, silicates : olivine, anorthite, labradorite, 

 and augite." 



It would still remain for me, with the view of concentrat- 

 ing in this place the greatest possible number of important 

 facts, taken apart from hypothetical anticipations, to point 

 out the many analogies which some meteoric stones present, 

 if regarded as rocks, with the older trap rocks (dolerites, 

 diorites, and melaphyres), and to basalts and more recent 



