5s ON THE ACTION OF AIR AND WATER UPON IRON. 299 
TasB.e VII. 
Deduced from the foregoing Table VI., showing the Average Loss 
of all varieties of Cast Iron, &c., experimented on in each 
of the five conditions of immersion for a period of 387 days, 
on one square inch of surface. 
Condition of Iron. om B. Y: 0. é. 
MER Cast Tron scscsis.c..1.. 6-826 | 6684 | 6025 | 5-478 | L372 
| Cast in Green Sand......sssseese- 6:781 2170 | 3:264 | 4:283 1-027 
No. 2. Bar Iron. Standard ...| 10-636 | 12°570 | 14:280 7-300 1:310 
Cast Iron; Skin removed ......| 8230 | 13°550 | 13:920 6:830 2-590 
| Cast Iron; Surface protected...| 4:214 7-110 2-466 3:096 0-488 
Tas_Le VIII. 
r 
_ Of the Average Amount of Corrosion in Clear Sea Water, of 
; various Cast and Wrought Irons, at the end of One Century, 
_upon one superficial foot of surface, deduced from results of 
Table No. I. 
ene 
Deduced ave-| Approximate 
Average rage loss of depth of 
less of Weight per | Corrosion in 
No. Class of Iron. Weight per | superficial | one century 
superficialfoot} foot ina due to this 
in 387 days. | period ofone| amount of 
century. loss. 
he grains avoir.| lbs, avoir. inch. 
| 1. | Welsh Cast Iron. Hot and cold ...... 859:°968 11°58 0:306 
2. | Irish Cast Iron. Cold.........:00se0ses00 860°400 11:59 0-306 
‘ 3. an Cast Irons. Scotch (as 948-960 12-78 0:337 
Welsh; Irish and Welsh, &c. ... 
| Scotch Cast Iron. Cold, and chiefly : : , 
” { hot blast ...... SeNuiso co cscuechisdeun sss ch ae a8 0379 
Staffordshire, Shropshire and Glou- 
| 5. cestershire Cast Irons. Hot and $| 1083:744 14-60 0°385 
| OIG ie «cnae ted tedes ans ocvarbreat Beaws 
q | Gray Cast Iron, mixed. Skin re- . P : 
# 6. moved by planing .........ssseee00 } aes tet 15:97 0-419 
ei) Derbyshire and Yorkshire Cast ; , Q 
| i. Trons. Hot and cold ............ } feet 16rd G4 
| Wrought Iron. Standard Bar. No. 4 : 5 
"| 8 { 2 FETE ha aR ee Ok: } 15sT584 | 20:56 0543 
