1919 



Hotson; on Sphagnum Dressinc/s 



223 



near a stove and that dried in trays in an ordinary Montreal workroom in 

 winter. In the first place, the temperature is probably over 100° F., 

 whereas, in the second, it is only about 65° F., but in each case the rela- 

 tive humidity is very low, probably ten or fifteen per cent. The moss is 

 thus almost completely desiccated. We have gone so far as to recom- 

 mend that in winter drying rooms should be kept just as cold as possible 

 for the work of the people. We have even discussed the advisability of 

 humidifying them somewhat after the method employed in certain branches 

 of cotton spinning."* There seems to be no objection to using artificial 

 heat, or any other means of drying, provided the drying is not carried 

 too far. For instance, it would be perfectly in accord with the facts thus 

 far known, to use artificial heat, say up to 90° or 100* F. at first, and 

 then finish the drying without artificial heat. 



In considering any apparatus for drying the greatest precaution 

 should be taken not to handle the. dry moss any more than is absolutely 

 necessary, and any contrivance that stirs or shakes it while drying should 

 be avoided as far as possible. Rough handling tends to break off the 

 minute branches and leaves which are the parts of the plant that make 

 it valuable for surgical work. 



PLATE 37 



The blower with 2 H.P. motor that supplies the air for drj'ing- the moss in 

 the trays in plate 38. This is installed in the Seattle Chapter of the Red Cross. 



■* P'rom a communication to the American Kcd Cross. 



