10 



3. Less putty is needed. 



4. The frost csiuiioL git iiiider the glass as readily as when lapped. 



5. The glass does not slip down if the lower light is well fixed 

 in plac*'. 



6. No air can penetrate between the joints. 



7. No more drip was observed than with the lapped glass. 



^ EVAPORATED SULPHUR, 



For the destructio)i of Mildeios and Insects in Greenhouses. 

 In the growth of plants under glass we meet with many parasitic 

 fungous growths and minute insects that are very destructive. Hav- 

 ing made some extended experiments with Evaporated Sulphur for 

 the destruction of mildews and leaf blights on the rose, lettuce, and 

 violets, and the minute insect known as the red spider, so injurious 

 to the leaves of roses and other plants, we give the following results. 



ROSE LEAF-BLIGHT. 



(Actiiionema rosea) . 



During the fall, the roses in the Durfee Plant-House were seriously 

 injured by large, dark brown or nearly black spots on the leaves, 

 covering in many cases the entire leaf, and soon causing it to wither 

 and fall. Upon investigation and inquiry it was found to be the rose 

 leaf-blight, Actinonema rosea, which was described and illustrated in 

 the report of the Section of Vegetable Pathology of the Agricultural 

 Department for 1887. 



To overcome the injury we began the use of evaporated sulphur, 

 which we had previously used for the destruction of the common rose 

 mildew and red spider. 



RESULTS. 



After a few weeks' use, no new spots developed on the leaves and 

 none have since appeared. 



THE REMEDY. 



This remedy consists in keeping a kettle or basin of sulphur (brim- 

 stone) heated to neai'ly the boiling point, in the room for three or 

 four hours twice or three times a week. The apparatus used was a 

 Florence or Monarch hand-stove with the sulphur in a thin iron ket- 

 tle. Enough sulphur must be evaporated to fill the room with the 

 vapor, so that it will be visible and give something of the odor of 

 sulphur. 



