CHAPTER LXX.
METHODS OF CASTING TEST BARS FOR
THE A. F. A. TESTS, COMPILATION
AND SUMMARY OF RESULTS.
Prior to about 1890, there had been felt for many years the need of tests on cast iron, to give those interested in its use reliable data of its physical qualities. I Some work had been done in an effort to obtain records
\ that could be used, but before the appointment of the
American Foundrymen Association's committee, in the
f spring of 1898, little of practical value had been
obtained aside from that presented in the first two , editions of this work. This was due in part to the
,, want of a broad experience in founding by experi-
!J mentors, and their inability to originate practical
|; methods for moulding and casting test specimens in
! the right manner. Some, for one example, started off
ff with an elaborate series of tests on one grade of iron
only, thinking that such would suffice, when in reality there are about a dozen grades that should be considered. Aside from this error the bars were all cast r flat, and at different pouring temperatures.
> The unreliability of records and systems for testing
that were pressed on the trade from 1890 to 1899 caused-the author to labor in every way he could to show wherein they erred, and to get others interested sum-2