the several Cast Irons of the foregoing experiments. 303 
Character in Working. 
crystals vesicular, often crystalline, 
Least fusible; thickening rapidly when 
incapable of being cut by chisel or 
fluid bya spontaneous “puddling;’ | 
file; ultimate cohesion a maximum, 
and elastic range a minimum. 
Very soft; feels greasy ; peculiar mi- 
caceous appearance generally owing 
toexcess of manganese; soils the 
fingers strongly; crystals large ; 
runs very fluid; contraction large. 
thick ; contraction on cooling a 
maximum. 
for working ; ultimate cohesion and 
elastic range generally are balanced 
most advantageously ; crystals uni- 
form; very minute. 
: f 
; Tough and hard; can be with diffi- 
culty filed or cut; crystals large 
i and small mixed ; sometimes runs4 
| 
Toughness and hardness most = 
L 
Less tough and hard than the ise 
ing; other characters alike; con- 
traction on cooling a minimum. 
exudes graphite on cooling; soils 
the fingers; crystals large and la- 
mellar; ultimate cohesion a mini- 
mum, and elastic range a maxi- 
mum. 
> |) L 
an 
3 f fusible, remains long fluid; 
L 
Specific 
Gravity. 
7603 
7624 
7624 
7629 
7527 
7158 
6°378 
7-015 
6-928 
6:980 
7000 
7308 
7-116 
7017 
7168 
7°138 
7-294 
7140 
7248 
7268 
7079 
7-134 
6-329 
7115 
7-152 
7141 
7-001 
7183 
7:074 
7064 
7-156 
7115 
7:097 
7:049 
7081 
7:074 
6°838 
7124 
7164 
6°809 
7109 
7:205 
7-152 
7-030 
7063 
7:020 
7107 
7159 
7192 
7143 
7:076 
7:073 
7:027 
6:978 
7-050 
How Cast, 
Chilled 
Sand 
Chilled 
Chilled 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Chilled 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Chilled 
Chilled 
Chilled 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Sand 
Observations. 
Maximum density. 
Fullof microscopic 
vesicles. 
Minimum density 
porous as No. 7. 
Minimum solid. 
