208 METALLURGY OF CAST IRON.
this work was M. Fred Gautier, of Paris, who, at the next spring meeting of the above association, presented a paper on silicon in foundry iron. These two papers started many others experimenting, among the most prominent being Mr. W. J. Keep, of Detroit, Mich., and the author.
Not only is silicon a softener of iron and a great element in cheapening the mixture by permitting a large percentage of scrap or cheap iron being mixed with high-silicon iron, but it is also an element of value in increasing the fluidity of metal. Silicon possesses a property which, in a degree, reduces the percentage of total carbon which iron may take up, and which also can exceed in its percentage any other element in iron. It has found such a favor in the estimation of some as to make them unregardful of any other element in iron, a practice which is decidedly wrong, from the fact that one part of sulphur can often neutralize the effect of ten to fifteen parts of silicon, and hence for this reason it is as essential that the founder should be as watchful of sulphur as silicon, and the same may be said of the total carbon, phosphorus, and manganese, as all should be considered in making mixtures ; but the silicon and sulphur should be considered the*bases for changing the grade or character of iron, as seen by Chapter XVII.
The author's experience and study of silicon in its effect upon mixtures lead him to affirm that while it can achieve much good, it can also do great injury. It is an element which should only be used with a knowledge of the effect any percentage can produce, just as a physician can administer a poisonous drug to obtain beneficial results. Silicon is a very good thing, so isor characteristic determinations of combined carbon in a fluid state, see Chapter LX, and the carbons, etc., in iron, as