94 FORESTRY IN EASTERN RUSSIA. 



compressed peat and one part, by weight, of charcoal is 

 charged, 2.8 parts of peat being considered equivalent to 

 one part of charcoal. 



' Prof. Jossa also gives soma details of the manufacture 

 of ferromanganese at one of the Nijni Tagilsk charcoal 

 furnaces. The ores used at the Nijni Tagilsk furnace 

 have the following composition : 



LEBJAZEJ MANGANESE ORE. 



Mn 3 4 , ... ... 64.5 



Fe 3 4 , 20.2 



Si0 2 , ... ... ... 10.2 



VISOKAJA-GORA MAGNETITE. 



Fe 3 4 , ... ... .. ... ... 90.0 



Mn 3 4> ... ... .. ... ... 0.6 



Si0 2 , 5.0 



A1 2 3 , 3.0 



CaO C0 2 , ... ... .. ... .. 0.9 



P, ... .- 0.02 



' The charge consists of 40 parts of well-roasted iron ore, 

 90 parts of manganese ore, 5 parts of calcined lime, and 

 some cinder from previous smelting. For every 126 pounds 

 of charge, 6.3 cubic feet of charcoal are used, and with 

 blast heated to 250 to 300 C., and 5.2 inches pressure, 

 60 charges are put through in 24 hours, the production 

 being from 1 to 1.5 tons of metal, having a percentage of 

 manganese ranging from 40 to 50 per cent. When the 

 furnace is working well, the cinder is yellowish -green and 

 fluid. As soon as the hearth is much worn out, the charge 

 is changed, and a pig rich in silicon is aimed at. On a 

 charge of 126 pounds of charcoal, the burden is 110 pounds 

 of magnetite and 17.6 pounds of quartz sand, the pig made 

 running from 3.7 to 9.5 per cent, of silicon. Recently, 

 silicon ferromanganese has been made, containing 40 to 

 45 per cent, of manganese, 3 to 7 per cent of silicon, 6 to 

 8 per cent, of carbon, and 40 to 45 per cent, of iron. First 

 iron rich in silicon is aimed at, and as soon as the furnace 

 is in good working order the burden on 126 pounds of 



