抄録
Sulphur Prints of the test pieces which contain different quantity of sulphur, have been printed under the same condition.
The condition is as follows : Oriental OK No. 4 is used as photographic paper, 3 per cent solution of dilute H2SO4, the colundum sand paper of Riken No. 7 for the surface polishing of the test piece, and pressing time of printing is 2 minutes. Prints show different darkness of colour according to the sulphur contents in iron and steel.
The auther has measured the darkness of these snlphur prints by Mean Densitometer, which was made specially for this purpose. And has found that the relation between the darkness of print and the per-centage of sulphur contents in iron and steel can be represented by a simple linear equation.
S=KD when S is per-centage of sulphur, D is density of the print, K is constant.
In this case, K is 0.214 Constant K varies according to the printing condition or kinds of photographic paper. This method is simple and rapid for the estimation of sulphur in iron and steel.
