7o Some Recent Advances in Science — 



There is another point which Dr. Sinclair mentioned — the 

 existence of dust in Belfast. I had been under the impression 

 that there was nothing but mud. I remember seemg a short 

 time ago an account of experiments made on a vessel at sea to 

 ascertain the quantity of dust and the number of microbes in 

 the air at sea. It was a well ventilated ship, one of the large 

 Atlantic liners, and the amount of dust and the corresponding 

 number of microbes seemed to be much the same as they were 

 anywhere else. On deck there were a few less, but only in the 

 very bows of the ship was there any marked scarcity of microbes ; 

 so that I am afraid it is not probable that there is any 

 possibility of getting rid of a large number of diseases by doing 

 something to the dust of a town (or the mud, as the case may 

 be), seeing that, on the top of a mountain, or in a ship at sea 

 with a good breeze blowing, we have practically as much dirt 

 and dust in the air as we have in an ordinary place in town. 

 As to Dr. Kerr's remarks, I think the reason for ventilating this 

 subject in a Society like this is that people hate to be treated 

 in the dark. They want to know as much as they possibly 

 can, and they want to be assured, as Dr. O'Neill has made 

 perfectly clear, that the doctors here will not recommend the 

 remedy unless they have some fairly satisfactory reason for 

 expecting that it will operate favourably. 



Dr. H. Sinclair, in reply, said : — I have to thank you all 

 for the very kind way in which you received my very imperfect 

 paper. It was not my intention to do more than take up the 

 bacteriological aspect of the question, because I think with 

 Dr. Kerr that a natural history society is not exactly the place 

 for discussing therapeutics and the treatment of disease. With 

 regard to what Prof. FitzGerald rnentioned — the occurrence of 

 microbes at sea in as large a number as they do in towns — I think 

 it is not so much the number of microbes as the kind of microbes 

 present which is of importance, and what I referred to more parti- 

 cularly are those known as pathogenic or disease-producing. Every 

 portion of the air contains large numbers of micro-organisms, but 



