34 Proposal for an Iron Tunnel 



The magnesia was precipitated by caustic polash : h 

 weighed, after desiccation, 16 grains. 



u°. The oxides of iron and manganese were dissolved in 

 an excess of muriatic acid, and pouring, by little and little, 

 saturated carbonate of potash into the dissolution until red 

 floccules were visible, and then leaving it to repose 24 

 hours, all the carbonate of iron precipitated, whilst that of 

 the manganese remained in the liquor. 



The carbonate of iron, after calcination, gave 24 grains 

 of oxide: and "that of manganese, deposited by ebullition, 

 by the same operation, only 1J-* — Which makes in all: — 



Silex 41 



Sulphur 24- 

 Chromic acid 2£ 



Alumine 1 



Magnesia 16 



Lime 3 



Oxide of iron . . 30 



Oxide of manganese ... . 1£ 

 Loss 3 



Total 100 



Analysis of the metallic iron isolated by the magnetic 

 needle* 1°. 100 parts of this stone gave 28 of metallic iron, 

 which is very brittle, owing to the nickel it contains. 2°. 

 40 grains of this iron were dissolved in nitro-muriatic acid, 

 and by means of ammonia in excess the oxide of iron 

 was separated, which weighed 45 grains. The dissolution 

 of nickel in this alkali was evaporated to siccity to expell 

 all the ammonia. The oxide of nickel was redissolved 

 by muriatic acid, and precipitated by the prussiate of 

 potash, which gave one grain of the prussiate of nickel. 

 We may infer, from these physical characters, and results 

 of chemical analysis, that this stone is like all other me- 

 teoric stones hitherto known. 



V. Proposal for constructing, and putting in its Place, 

 an Iron Tunnel under the River Thames. By Colonel 

 Lennox. 



To Mr. Tilloch. 



Sir, 1 herewith send you a plan for a tunnel under the 

 Thames, which I hope you will not deem unworthy of a 

 place in your valuable Magazine. 



Being 



