FOG, FLOWERS, AND FOLIAGE 51 



Charcoal seems to be by far the best filtering medium. 

 There is a Mr. Toope, who, in a small conservatory at his 

 offices at Stepney, is endeavouring to cultivate a collection 

 of orchids and other stove plants in safety by the use of 

 charcoal filters and w^armed air. 



The method he uses is ingenious. Boxes containing 

 open-work trays, upon which sticks of charcoal are loosely 

 placed, are set upon the floor under the staging. These 

 communicate with the exterior by means of apertures 

 which can be opened or closed at will. The air (fog 

 and all) is led from outside through these trays, passes 

 the charcoal, impinges upon the hot-water pipes, and is 

 then allowed to reach the plants. Draught is regulated by 

 valves. Results so far are considered very encouraging, 

 but not convincing. Mr. Toope has other things to 

 occupy his attention, and sometimes has to trust his pets 

 to others ; if it were not for this, he thinks he would 

 ensure a greater measure of success. 



It seems curious to think of plants taking to respirators, 

 just as human beings have discarded them ; but the use 

 of charcoal does sound common-sensible. We are all 

 familiar with the extraordinary power charcoal has of 

 absorbing and oxidizing the products of decomposition of 

 organic matter, and of rendering harmless the greater 

 number of easily alterable gases and vapours. A few 

 years since, after some nursing lectures at the Royal 

 Hospital for children and women at the Waterloo Road, 

 the following examination question was put to the 

 students : " How would you ventilate a room of a small- 

 pox patient on the night of a dense fog ? " The question 

 puzzled us all. We were told the right answer after- 

 wards. " Open the window at the top, and hang up a 

 blanket." This appeared to me to be a stifling arrange- 

 ment ; as at present advised, I would treat patients as 

 Mr. Toope treats his plants, and give them charcoal filters 

 instead of the blanket. The chemist Stenhouse has 



