218 Ozone and the Atmosphere. 



oxygen, most oi the time to a slow continuous current. A few- 

 light spots appeared on the azalea and nasturtium, and there was 

 a slight discoloration of the camellia. Similar specimens,left for 

 3 hours in an atmosphere containing sulphurous acid, changed 

 oreatly : the camellia became lighter in spots and finally pink 

 throughout, the azalea turned yellow and finally white, the 

 Abutilon venosum saffron-yellow, the change beginning at the 

 outer edge of the flower, the cineraria was somewhat lighter in 

 color, the Salvia splendens white in spots, other portions red. 



The Ixia had become white, the long ends of the mimosa 

 {Ingd) were also bleached, the reddish markings of the nastur- 

 tium had quite disappeared. The flowers of the Bouvardia 

 were bleached at their outer edge ; in the Strelitzia, neither 

 flower nor leaf was affected. The same is true of the leaves 

 of all the specimens. 



After eighteen hours more of exposure, the yellow portion of 

 the Strelitzia was not affected, but the blue had become quite 

 white ; the mimosa was a faint pink, the nasturtium a deep 

 yellow throughout, and the Salvia bleached entirely. Even 

 after this length of time, the chlorophyll o f the leaves had un- 

 dergone no change. When these same flowers w T ere transferred 

 from the sulphurous acid to a current of ozonized oxygen, the 

 azalea turned red on the edges and colored somewhat through- 

 out ; the camellia reddened, so likewise the mimosa; Xhe Abu- 

 tilon became red along the veins, the petals of Ixia turned red 

 at the edges, the nasturtiums reddened in places, the Bouvardia 

 became brown, the Strelitzia did not change. 



When similar flowers, which had been longer exposed to 

 ozone without change, were placed in an atmosphere contain- 

 ing chlorine, the camellia became buff color, its leaf unaf- 

 fected ; the azalea turned yellow, then white, its leaves partly 

 changing also ; the Ixia and Bouvardia became perfectly 

 white; Salvia, yellow- w r hite, its leaves yellow. The red veins 

 of the Abutilon venosum were not bleached, but its green 

 calyx and part of the stem were. The leaf of the Abutilon 

 insigne w r as bleached in spots; the leaf and stem of the nastur- 

 tium became entirely white. The blue portion of the Stra- 



