428 THANSACTIONS OF THE 



Dr. Vanderweyde thought that the ink was a chemical one, and not 

 Indian ink as suggested. 



The following extracts were sent in by Judge Meigs. 



Repertory of Patent Inventions. London, March, 1869. 

 PHOTOQALVANOGRAPIIY. 



Very interesting as information to the Club, but useless to print, because 

 contained in a work readily accessible. — J. R. 



The Institute has recently received from " The Societe Imperiale des 

 Sciences Naturelle," of Cherbourg, a present of the 5th volume of their 

 Transactions, containing a second note by M. J. Thuret, on the Fecunda- 

 tion of the Fucacece, and the reproduction of Nostochinea, the anotomy of 

 aerial plants of the order of orchideee, by M. Ad. Chatin. 



The regular subject of the evening being now in order, viz : 



STEEL AND MALLEABLE IRON. 



Mr. Seeley introduced the subject, by stating that we want light on the 

 relation of steel to iron. Some suppose steel to be iron, which has suffered 

 a molecular change only, and that carbon is but an accidental substance 

 and not necessarily present in steel. He, himself, holds that steel is a true 

 chemical compound of iron, carbon, &c., and that cast iron differs from 

 steel in the amount of carbon, &c., which it contains in proportion to the 

 iron. In the process known as Bessimer's, for converting cast iron into 

 steel, the oxygen of the air is caused to combine with all the impurities 

 which are oxydizable, which are thus carried off in slag to any extent re- 

 quired to form the compound steel from the compound cast iron. The 

 great problem, however, of this process has yet to be solved, viz : " To pro- 

 duce a homogeyieous mass, by throwing jets of air through fused masses of 

 cast iron." Mr. Seeley understood that Joseph Dixon, Esq., of Jersey 

 City, claims that he can produce steel from iron, by keeping the latter at 

 a bright red heat for fourteen days, and out of contact with the air. He 

 must be mistaken ; there is high authority against him. 



Dr. Vanderweyde. — The whole of Mr. Dixon's theory is wrong ; nitrogen 

 must be present, and yet it is so svibtile that it escapes detection by the 

 chemists in analyses. Steel is never made unless where nitrogen is present. 

 In fact, this element performs an important part in all instances of case- 

 hardening. 



Mr. Tillman. — If I recollect aright. Professor Faraday was the first to 

 refer to nitrogen as an element of steel. There are, I believe, records of 

 iron having been converted into steel, by the agency of electricity. Alu- 

 minium is found as an element of Indian steel. ISow the chemical equiva- 

 lent of aluminium is the same as that of iron, and this relation may be very 

 important in this connection. It may be well to add th,at nitrogen has the 

 equivalent one-half in this scale. 



I do not believe the combination to be atomic, as stated by Mr. Seeley, 

 in any kind of steel; and the number of processes patented, which are 

 diametrically opposite in chemical, theory, show that the subject is not 



