192 
apparatus, and uniformly with the same care. The dates of 
the experiments are also recorded. 
1. In August, 1840, a bar of cast iron of the dimensions 
already stated, viz., 12 inches long by 1 inch square, made 
from the Bierley Company's regular No. 3 pig, sustained ere 
it broke, 24 cwL Another bar was taken which was cast at 
the same time, and from the same metal, which broke with 
25 cwt. 
Note — These two bars were cast in green sand. 
With the same metal, and at the same time, w^ere cast two 
bars in dry sand ; one of which broke with 22 cwt^ and the 
other with 22 cwt, 3 qrs. In both these cases, the weaker 
bars seemed to be slightly unsound in the fracture, but the 
grain was strong and of a bright blue colour. 
2. About this time two bars were cast in green sand, from 
the regular No. 3 pig, made at the Elsecar Iron Works, each 
of which broke with 21 cwL 2 qrs. At the same time, and 
from the same metal, two bars were cast in dry sand ; one 
broke with 20 cwt., and the other with 20 cwt 2 qrs. The 
fractures were very sound and fine grained. 
Note. — The fractures of all the green sand castings pre- 
sented a strong white skin on the surface of the bars, caused, 
it is presumed, by the moisture or dampness of the green 
sand moulds, the absence of which in the dry sand moulds 
is no doubt the reason why the green sand are stronger than 
the dry sand castings. But this advantage is only obtained 
in small green sand castings ; for it is well known that large 
masses come out of dry sand moulds much stronger and 
more regular in their grain than out of green sand moulds. 
3. May 6th, 1841. — Two bars were cast from the regular 
No. 3 pig of the Low Moor Iron Works, which broke, one 
with 18 cwt, 2 qrs,, and the other with 19 cwt. 
Note The latter bar w^as cast while the metal was hot 
and fluid, which presented in its fracture a close short grain 
