578 Dr. Schafhaeutl on the Different Species of 



Ingredients. 



Gray 



French 



Iron. 



Carbon and Azote 3"412 

 Silicon 0-138 



White 

 Welsh 

 Iron. 



5-3920 

 ^1-008 



Iron 



from 



Creuzot, 



2-086 

 0-702 



Iron (fl). 



6-5000 

 0-4804 



5-2696 

 0-4804 



4-02 

 0-23 



3-5190 

 0-4804 



Steel. 



1-7265 

 0-2740 



Last residuums after ignition and extraction by acids. 



Carbon, Hydrogen 



and Oxygen 3-700 



Silicon 4-812 



gray. 



3-276 

 1-009 

 gray. 



(3-580) 

 1-000 

 gray. 



4-7600 

 1-8500 



3-811 

 2-006 



0-912 

 0-473 



2-9754 

 2-8671 



0-3230 

 0-5191 



We here see the combination of carbon with silicon, the 

 quantity of which is almost always constant. If we further 

 consider the different relations of the numbers in the above 

 tables, we find that the white irons [a] (b) (c) [d) are charac- 

 terized very distinctly by the different proportions of carbon 

 and silicon. Specimen (c) was very difficult to treat in the 

 refining furnace, as well as in the puddling oven, and was of a 

 large roundish grain, silver white, and contracting very much 

 during the process of cooling. Specimen (d) was almost in- 

 fusible in the refining as well as the puddling fires, and pro- 

 ducing an iron red-short as well as cold-short, which would 

 not weld under any circumstances. The quantities of sul- 

 phur and arsenic cannot be the cause of these singularities, 

 as both ingredients are found in a less proportion in (c) 

 and (d) than in the specimens (a) and {b). The silicon 

 alone |s predominant in the last specimen ; but if we com- 

 pare its quantity of silicon with that contained in the first 

 analysed gray iron from Vienne, we find it there in twice as 

 great a proportion. Nevertheless the iron ran as liquid as 

 water. The real cause of the difference in quality of those 

 two last specimens must therefore be sought for in the differ- 

 ent proportions of carbon and silicon combined, and, in reality, 

 the tables show us, that the quantities of silicon in relation to 

 the carbon increase in proportion as the different specimens 

 become less and less fusible. It therefore naturally follows, 

 that the more carbon becomes combined with silicon, the less 

 carbon will be combined with the iron, and consequently our 

 residuums will show the property of becoming ignited by a 

 low degree of heat, and, in fact, the residuum of the last 



* If we compare the silicon left by chlorine in the white Welsh iron, 

 we find it equal to the actual determined quantity of silicon. In all other 

 specimens the chlorine had carried away all or a great part of the silicon, 

 viz. where it was combined with the iron, as in the cast iron from Vienne. 

 But in this specimen only almost the whole of the silicon seemed to be 

 combined with carbon, on which combination chlorine never acts. 



