AMERICAN INSTITUTE. 545 



Prof. Mapes would like to know, whether the hardness of franklinite iron 

 was due to the presence of zinc or not ? Practical men say the hardness 

 exists always with zinc, never without; and hardness is the valuable qual- 

 ity we want to determine. 



Mr. Pomeroy. — There must be some cause to produce the crystallized 

 white pig metal with an amorphous crystallization, some crystals being 

 harder than others ; if the metal be run into a mould of wet sand it will 

 crystallize differently from what it would if run into one of dry sand. Thii 

 iron takes up carbon. If it has not been fully scorified, all the impurities 

 may not be taken out ; they may cause this hardness, but the zinc cannot. 

 When the iron is perfectly scorified and carbonized, it forms an ordinary 

 east iron of good quality. 



Prof. Mapes. — I have seen plates crushed out of this metal, the crystal* 

 lization being destroyed, and yet it was extremely hard. 



Melting point being called for by the President — 



Mr. Butler could not give the degrees, but in experiments in a circular 

 oven of coal, giving a low white heat to low bar iron, or a high red heat, 

 the metal flowed at a brilliant red, and when covered with borax it flowed 

 around and all over the iron, its surface giving a perfect mirror. At ordi- 

 nary red heat it would chill. 



Red heat is about 1,000°, and white heat about 1,850°, so Mr. Butler 

 judged the melting point to be about 2,000°. 



Mr. Pomeroy. — There are no means of making a thermometer which will 

 measure directly temperatures as high as the melting points of the metals ; 

 there is, therefore, no definite measure for them, and we are left partly to 

 conjecture. The melting point of iron is about 2,500° Fahrenheit. In 

 this metal there is no graphitic carbon — that is, iron combined with an 

 excess of carbon — it is simply a kind of steel, and if thoroughly scorified — 

 deprived of impurities — it is pure steel of the best quality. It is, proba- 

 bly, the most important mineral at this moment on this continent. As to 

 its separating from iron which has been plated with it, the thing is impos- 

 sible ; it is molecularly united with the iron ; they consequently cannot be 

 separated. Good bar iron can be made from ordinary ores by the aid of 

 franklinite at one-half its present price. 



The President inquired whether this mineral had been found in any 

 locality in Europe? On this subject there was no definite information, but 

 Dr. Stevens mentioned some few localities in England where accidental 

 specimens were found — probably mineralogical specimens which had been 

 lost from cabinets. 



Mr. Johnson mentioned some interesting experiments tried with frank- 

 linite, to make alloys of it and copper, silver, &c. He had noticed a speci- 

 men of copper so alloyed to become more sensibly magnetic than the frank- 

 linite metal, but still only feebly so. 



Mr. Pomeroy stated that all metals will fuse at low temperature if the 

 [Am. Inst.] 35 



