ON THE ACTION OF AIR AND WATER UPON IRON. 35 
First Course of Experiments. First immersion. 
Wrought Iron, Steel, and Zinked Iron. 
at one o’clock p.m. (The lid of box draws off to the right of observed; numbers read from 
and removed with Box a. No. 1, January ‘12, 1842; hence immersed 732 days. 
F&C. Fibrous and Crystalline. FC. Fine Crystalline. C. Crystalline, é. e. mean size. 
No. 13. Wrought Iron and Steel. 








— 
im 
11. | 12. 13. 







2 » a] 
S85 | S08 |s., 2 
See |S3q ae: ee 
485 /1% FES 8 Character of Corrosion. er 
efq| ese | os 3 
ow o*S |'o S 
Ha | 21s 
—— eee a | SS 
0: | Skin at the sides sound, ends fibrous .....seesescseneeensveesete POSE C Hot 
0: | Fibrous at sides and ends........., Beer phiecigae sate et: 4 seqhape rose Hot 
0: | Fibrous at sides and ends, principally at sides......sescesseee abajepes +.|Hot 
0: | Straight fibre uniformly exposed, lustre silvery ...... gage oweniagswive «04 Cold 
0: | Fibre everywhere exposed, small patches of skin sOUNd...++4.«++++++0¢ Cold 
0: | Fine distinct lamina, perpendicular to sides, ends and edges smooth. | Hot 
0: | Fibre straight, uniformly exposed......... teeceececdenccasennaceessneveese Hot 
0: | Fibre equally exposed all over...........+. icceetes cegssens Cold 
0: | Fibre visible all over, but skin sound on edges.........ssseeceereeessenes Hot 
0: | Fibre not very apparent, tangled....,..... phececsedopenss dim stare te seecoee| Hot 
0: | Fibre exposed at ends, skin sound on sides, action local.......«+- »e+e{Cold 
0: | Fibre uniformly and beautifully developed. .........+4+ sneosaecesnoaseesf{COld 
0: | Edges lamellar, sides smooth and uniformly corroded.......0.-+er++ess Cold 
0: | Fibre developed at ends and edges, corrosion local .............++se+++ + 
0: | Corrosion nearly confined to the ends, reduced to fibrous brushes. |Cold 
0- | Fibre visible, corrosion nearly unifOrm..........cecscseeceeseseecesereenees % 
0: . | Fibre visible, corrosion nearly uniform ,...45...-eeeeesees epededqnanas +--«{Cold 
0: | Fibre developed, subcrystalline, corrosion nearly uniform .......++++ hy 
0: | Corrosion nearly uniform, smooth, no fibrous structure visible.......} ,, 
0: | Crystalline structure developed, plumbago of a silvery lustre .,..... i 
0: | Fibre scarcely visible, corrosion unifOrm .........ces.sceseneeneeecesentes F | 
0: | Without fibre, smooth, locally pitted .....cecccs.cecceeee Pree APR RS Fe A 
0: | Without fibre, smooth, nearly uniform....... aasnwdeudssapaiansene em sabiiins 
0: | Fibre scarcely visible, corrosion nearly uniform ...........e0essseeseeees 


| i 3:83 | 0-432 |0-0 { Corroded at the ends slightly, zinking, black, brittle, and easily 
detached. as 
‘2-40 | 0-270 14-0 { Paint still visible, but reduced to oxides of zinc and iron, skin of a7 
metal sound.......... DG UseNeach Vavetbecectaseteatamreesacadexast svaseduae 
D2 
