Discussion on "Recent developments in the measurement and control of surface roughness" at the London Section of the Institution

MR. DAVID CLAYTON (National Physical Laboratory) : I have been venturesome enough to enter this field of roughness measurement and would like to raise some points which have occurred to me. My instrument, which Mr. Shaw has not mentioned, was described in Engineering in March of last year. I can congratulate Mr. Shaw on his device for getting horizontal distribution in his diagram without the trouble of a gearing system. It is very neat. My own apparatus has not got to the stage of being made autographic, as it was designed for a particular job and the expense was not justifiable ; but I think I should certainly adopt Mr. Shaw´s idea if I did make it autographic.