Cast Iron, Steel, and Malleable Iron. 303 



By treating iron with diluted hydrochloric acid, the sulphur 

 escapes almost entirely as sulphuretted hydrogen ; the same is 

 the case with antimony escaping as antiraoniuretted hydrogen. 

 On the contrary, scarcely any portion of the arsenic escapes 

 with the hydrogen. 



The case is different when iron is treated with nitric acid. 

 When fragments of iron are treated with nitric acid of such 

 a specific gravity that the iron is moderately attacked in a re- 

 tort whose beak is connected with a solution of carbonate of 

 barytes and acetate of copper or lead, and only a slight evo- 

 lution of binoxide of nitrogen takes place, the nitric oxide is 

 then first absorbed by the air in the uppermost part of the re- 

 tort, and a partial vacuum is produced which makes the liquid 

 rise in the beak of the retort several inches. A few hours af- 

 terwards pure azote is evolved, acting neither on the carbonate 

 of barytes nor on the acetates or nitrates of metals. Shortly 

 after, the evolution of gas again ceases, and after the action of 

 the acid on the iron stops, a new partial vacuum is produced 

 and the liquid is found to stand in the beak of the retort several 

 inches above its level. 



For example, I took 20 grains of dead gray cast iron from the 

 forges of Creuzot, departement de Saone et Loire, treated it 

 with hydrochloric acid specific gravity 11 '5, and left residuum 



inspection I found those lumps covered with stalks of a black vegetation, 

 exactly like the mould on ink or sour starch paste, and diifering only in 

 colour ; the stalks were from about a half to three-quarters of a line in 

 height, and terminated with a little knob on the top. The next day the 

 little knob on the top assumed an orange red, and on further exposure to 

 the air, the stalks became of the same colour. 



Viewed through the microscope, these little mosses appeared opake, of a 

 varnished yellow colour like the petals of Everlasting, and having a long 

 curved cylindric capsule on the end. The capsule was alternately expanded 

 and contracted very similar to the duodenum of animals, and curved into a 

 circle, so that the end almost met the point when the capsule was attached 

 to the stalk ; and when viewed under the microscope superficially, the knobs 

 appeared to consist of a perfect ring fixed to the stalk. I found only one 

 stalk, which shot forth two of these capsules from the same point, curved 

 up just like the horns of a ram. No operculum could be discovered; the end 

 of the capsule was found perfectly rounded like a globule with rather a nar- 

 row neck, and when pressed with a fine needle, the capsule burst, emitting 

 extremely fine seeds, exactly like the genus Phascum. No traces of leaves 

 could be detected, unless we reckon some entangled and interwoven black 

 filaments on the surface of the decomposed iron. Not being sufficiently ac- 

 quainted with the cryptogamic branch of botany, I am not able to decide 

 on the generic character of these small vegetations. 



On the retort being packed up in moss and afterwards washed with rain 



water, the seeds of the moss must have been derived from one of these 



sources ; but the most extraordinary circumstance is their becoming fixed 



in these decomposed fragments of cast iron, serving as a very fertile mould, 



. and growing rapidly in hydrochloric acid gas and sulphuretted hydrogen. 



