THE USE OF IKON. 59 



of two processes, the Bessemer and open-hearth, either acid 

 or basic. 



At present there are no limitations fixed by the manufac- 

 turers' standard specifications in the matter of process of 

 manufacture, one of the initial clauses of these specifications 

 being " Steel may be made by either the open-hearth or Bes- 

 semer process," and no notice of the further refinement possibly 

 resulting from the character of the furnace-lining is taken; 

 notwithstanding this, each process of manufacture has its 

 ardent advocates. 



Comparative Homogeneity and Strength of Bessemer and 

 Open- hearth Steels. The Bessemer or converter process 

 attaining its highest commercial development when operating 

 upon a grand scale and in supplying an immense output, it is 

 questionable whether such conditions are as favorable for 

 scientific and exact production of steel as the less extensive 

 furnace or open-hearth system, and where, at any period of 

 evolution, tests may be made with regularity and certainty, 

 and the process discontinued at the precise moment deemed 

 most suitable. 



In addition to the requirements of the manufacturers' stand- 

 ard specifications, the American Boiler Association demands 

 4 ' homogeneous " metal. If the initial metal is low in phos- 

 phorus and sulphur, the finished product may be sufficiently 

 uniform for all practical purposes, but entire and absolute 

 homogeneity and absence of segregation is at this time unat- 

 tainable, but from the fact that in the acid open-hearth pro- 

 cess the phosphoric and sulphuric components of the charge 

 remain unaffected during the process of evolution, it is pos- 

 sible that this .system of manufacture should be given a prefer- 

 ence. This reasoning applies with equal force to the favor 

 shown by some engineers toward the acid rather than the 

 basic method of production, a definite allowance of some two 

 or three per cent, sometimes being permitted, the idea being 



