266 MR. R. A. SMITH ON A SEARCH FOR 



XX. A Search Jor Solid Bodies in the Atmosphere. 

 By R. Angus Smith, Ph.D., r.R.S., &c. 



Read March 31st, 1868. 



I HAVE SO frequently for many years attempted to find, 

 and have found, organic substances which have passed from 

 the air into the liquids in which they were collected, that 

 perhaps the Society will scarcely attend to another attempt, 

 although it indicates, I think, some progress. It was in 

 the year 1847 "^^^^ ^ ^^^^ collected what I believe was 

 matter from the respiration and perspiration, and found 

 that as it was kept it grew into distinct confirmed forms. 



Whilst examining some matters relating to the cattle- 

 plague, I found one or two remarkable points. I had 

 before that time used aspirators to pass the air through 

 liquids, except in the oxidation experiments. At that 

 time I used simply a bottle which contained a little water. 

 The bottle was filled with the air of the place, and the 

 water shaken in it. The difference of air was remarkable. 

 A very few repetitions would cause the liquid to be muddy, 

 and the particles found in many places were distinctly 

 organic. 



Before speaking of my last experiment, it may interest 

 the Society first to hear of a few of these previous at- 

 tempts, the latest made till recently. I shall therefore read 

 from a report to be found in the appendix to that on the 

 cattle-plague. 



^'^Mr. Crookes also brought me some cotton through 

 which air from an infected place had passed. It was ex- 

 amined at the same time. Taking the cotton in the mass, 

 nothing decided was seen ; but when it was washed, some of 

 the separate films were coated over with small nearly round 



