The nine specimens, one from each Of the steels in both the B. O. H. And A. O. H. Series for each heating, were fastened three in a row to a piece Of rather coarse iron Wire gauze, which was wrapped around the pyrometer tube at the closed end in such a way that the' three rows of specimens-were placed approximately equidistant around the outer circumference Of and in contact with the pyrometer tube and also so that the hot junction of the chrome] alumel thermocouple, used in conjunction with a millivoltmeter, was approximately centrally located within the cluster of the nine specimens.