effective is the new process, that even from the poorest grades of pig
may be obtained economically an iron equal in quality to the refined
irons made from the best pig by the ordinary process of puddling.

Numerous tests of the Chapin irons have been made by competent and
disinterested parties, and the results published. The samples here
noted were cut and piled only once from the muck bar.

Sample A was made from No. 3 mill cinder pig.

Sample B was made from No. 4 mill pig and No. 3 Bessemer pig, half and
half.

Sample C was made from No. 3 Bessemer pig, with the following results:

Sample. A B C
Tensile strength per sq. in. 56,000 60,772 64,377
Elastic limit. 34,000 .... 36,000
Extension, per cent. 11.8 .... 17.0
Reduction of area, per cent. 65.0 16.0 33.0

The tensile strength of these irons made by ordinary puddling would be
about 38,000, 40,000, and 42,000 respectively, or the gain of the iron
in tensile strength by the Chapin process is about fifty per cent. Not
only so, but these irons made in this manner from inferior pig show a
higher elastic limit and breaking strain than are commonly specified
for refined iron of best quality. The usual specifications are for
refined iron: Tensile strength, 50,000; elongation, 15 per cent.;
elastic limit, 26,000; reduction, 25 cent.