CHEMICAL SCIENCE. 223 



form cyanide of potassium, and under this combination it is permanent so 

 long as kept out of contact with decomposing agents, as with oxygen and 

 the elements of water, etc. 



In the presence of our atmosphere, with its affluence in nitrogen, why 

 should we ever ascribe to that element some merely negative attributes, or 

 properties serving only to control or modify the more vivid action of some 

 other element? Why dwell only on its ozotic action, or on its assumed mere 

 modifying action among the phenomena of animal or of vegetable life? An 

 element existing everywhere, touching everything, penetrating, permeating, 

 and by ditfusion intermingling itself with every gaseous body it comes in 

 contact with, might be supposed a priori to exercise other functions (and 

 many) besides the merely negative ones usually assigned to it. And, among 

 other speculations that naturally arise out of these questions, is it quite im- 

 possible that the play of colors peculiar to heated steel, the assumption, for 

 example, of the pure blue and the purple, may not, in reality, be due to 

 some phase of development of some of the forms of ferrocyanide of iron? 



We possess another evidence of the use of nitrogen, from another and 

 unexpected quarter. It is on record, as a practice of the Indian " Wootz " 

 steel-maker, that, along with his iron or imperfect steel in his melting cruci- 

 ble, he places, as his carbon-giving material, the wood of the Cassia a^tri- 

 culata, and covers the whole earth with the leaves of the Convolvolus laurifolia, 

 both vegetable productions, rich in azotized matters. These, placed in his 

 closed crucible, will give an azotized carbon in contact with the metal. And 

 what may have been the origin of this far-back practice of the East this, 

 to us, apparently empirical handicraft of some Indian artificer? Has it 

 originally been the fruition of some mere accident, or of some induction or 

 deduction or is it a relic of some state of civilization and of science supe- 

 rior to those of the West? The Sheffield artisan seeks, even up to the 

 present day, that which the Indian artificer had found out ages ago. 



But howsoever all this may be, whether the nitrogen exist as an essential 

 constituent in steel, or its office be one of agency only, the practical applica- 

 tions for manufacturing purposes that flow out of the above collection of 

 facts, are in no way aifected by the tenability or the contrary of any theory 

 of combination. The fact of the important part, in the conversion of iron 

 into steel, that is played by nitrogen and carbon conjoined, and particularly, 

 when in the form of cyanogen compounds, is incontestible, howsoever may 

 be explained their mode of action. 



It is the experience of the writer, in his examinations of iron that is de- 

 ficient in malleability, that this deficiency is due as well, and even more 

 frequently, to the presence in such iron of unreduced oxide disseminated 

 throughout the mass, as to the presence and action of sulphur, phosphorus, 

 and other matters to which this deficiency is most generally attributed. This 

 fact seems also to have attracted the attention of Mr. Bessemer, who alludes 

 to it in one of his recent specifications. Now, the reducing action in metal- 

 lurgic operations of alkaline cyanogen compounds is well known, and hence 

 is suggested the possibility of employing them as well to remove from 

 impure iron the sulphur, phosphorus, and silicium, as to effect the complete 

 reduction to the metallic state of any oxide of iron disseminated through 

 the ores. But these alkaline cyanogen compounds, ferrocyanide of potas- 

 sium for example, when added to molten, impure iron, whilst exercising 

 extraordinary purifying effects, leave the metal finally in the condition of 

 steel. Here, then, is another problem, how to take advantage of these 



