Document DDdKnMo4YJ3jp7016ZMVLO2K5

the basic mechanisms of action, the problem of defining the thing that we're talking about ma7 become easier, and it would seem to me that our.afternoon session, therefore, should contribute in a Tory useful way, to easing that difficulty as it appeared in the morning discussion. We have, as you all see, a series of talks on The Inhalation of Certain Industrial Substahees, beginning with the old one of silica And going through to some of the newer materials and some of the newer concepts with regard to the action of dust in the lung. I understand that some of the people in the back of the room this morning had difficulty in hearing the various speakers, so that I will now ask the speakers this afternoon to keep their voices up, keep that in mind, and to make sure that they speak up loudly. I was provided by Doctor Vorwald with a program in advance, in which he has carefully noted the number of minutes allowed for each speaker. Since we are a little late in starting, I shall pound the bell down here very > promptly to make sure that they stay within their time* The first subject this afternoon, under this gen* oral heading of inhalation of certain industrail substaneesj is a discussion by Mr. Durkan of the Laboratory Staff on Silica. I'm sure Mr. Durkan needs no further introduetlas than that to us. Hr. Durkan. 1 SEVENTH SARANAC -0120