1 i j 



Mr. L. Fletcher. 



.In//'//*/'* of a [Fel>. 15. 



It may be added that the microscopical characters of mil 

 have now been so minutely investigated that, for mere determination 

 of the mineralogical species of the constituents, the microscopic 

 nnationof a thin section of a meteorite by the petrologist is 

 more complete and expeditious than a chemical analysis. 



The following numerical results were deduced from the observa- 

 tions, an account of the technical details of which will appear in the 

 ' Mineralogical Magazine': 



I. Mineralogical Composition of the Stone. 



(a.) After weathering 



Metullic iron .............................. 1'35 



Metallic nickel (cobalt) .................... 1'08 



Copper .................................. trace 



Oxide of iron (Fe s O,) ...................... 3'48 



Olivine (including glass and substance resem- 



bling glass) .......... .................. 48-61 



Enstatite ................................ 38"40 



Troilite .................................. 5'94 



Schreibersite ............................. 0'63 



Chromite .......................... > ..... 0'31 



100-00 

 (6.) Before weathering 



Nickel-iron ................................ 5'2U 



Olivine .................................. 49'08 



Enstatite ......... ..................... 3877 



Troilite .................................. 6-00 



Schreibersite .............................. 0'64 



Chromite ., .............................. 31 



100-00 

 (c) Ratios of constituents 



100 parts of the silicate portion would consist of 55'87 parts 

 of olivine and 44' 13 parts of enstatite. 



100 parts of the original nickel-iron would consist of 78'94 of 

 iron and 21'06 of nickel (cobalt) ; the analysis of 0'1450 gram 

 of the residual nickel-iron gave 82 per cent, of iron and 18 per 

 cent, of nickel (cobalt). 



The nickel and cobalt are in the proportion to each other of 

 4'7 : 1, or of 12 : 1 ; the former proportion was deduced from the 

 analysis of reduced rust, the latter from analysis of the mercuric 

 extract of the residual unrnsted alloy itself, which may have a 

 different composition. 



