OF ARTS AND SCIENCES. 345 



texture on cooling is highly crystalline and porous. Although the 

 iron in this state is as pure chemically as any bar-iron, its mechanical 

 state does not assimilate it to malleable iron, and the ingots rarely 

 present the compactness of cast-iron of the coarser qualities. A 

 careful examination of the specimens suggests the conclusion, that 

 much of the character of fluidity is also due to the presence of the 

 engaged carbonic oxide, which, like any gas disengaging from a 

 dough-like semi-solid, causes it to flow. 



" This mechanical constitution of the pure iron removes the diffi- 

 culty which every iron-master must have conceived to exist, in the 

 descriptions of the new method heretofore published, and it will be 

 seen that the eflfects produced in the old and new process are strik- 

 ingly similar ; Avhile the fuel in the one case is iron, in the other the 

 ordinary coke or coal. In removing the iron from the furnace, the 

 puddler depends on forming a rude porous aggregate, while Mr. Bes- 

 semer, by a refined mechanical agitation, converts the whole into a 

 semi-solid, crystalline mass, full of gas-bubbles, which flows from 

 an inverted vessel, and takes the forms of the moulds." 



Mr. Charles Jackson expressed a doubt as to the practical 

 value of the new process, and adduced the significant fact, 

 that it had not in the least affected the price of iron in the 

 market, nor the value of iron-works. 



Dr. Hayes rejoined, that he had presented to the Academy 

 only the interesting chemical points, avoiding the economical 

 bearing of the discovery. He was, however, prepared to 

 discuss this fact, in view of its importance to the English, 

 rather than to the American manufacturer. 



Professor Gray presented, in the name of Dr. Engelmann, 

 the following 



" Corrections and Additions to the Synopsis of the Cactacece of the 



United States. 



" On p. 279, the var. minor of Cereus dasyacanthus should be can- 

 celled, and after C. longisetiis, p. 280, the following added : — 



" 93. C. RcETTEEi, E. in B. C. E.. : ovato-cylindricus, 10- 12 costa- 

 tus ; areolis ovato-orbiculatis ; aculeis e basi bulbosa subulatis-rubellis 

 apice obscuris exterioribus 10 - 15, interioribus 2-5 robustioribus 



VOL. III. 44 



