170 MILDEW ON THE ROSE. 



the disease, very few agree as to its origin or cha- 

 racter. From our observation it appears to be 

 most common, where extremes of temperature pre- 

 vail; even in the open air this is plainly seen; in 

 July or August, we occasionally have a few cold 

 nights, succeeded by rain and warm weather, and 

 as certainly as that kind of weather occurs, as cer- 

 tainly does the mildew follow. It is rarely seen in 

 our collection of roses, few of which are kept in 

 high temperatures, and when it appears, a few 

 syringes of sulphur water are applied, which de- 

 stroys it. We prepare sulphur water, by placing 

 in a small barrel a piece of unslacked lime, about 

 the size of a double list, with five or six pounds of 

 flowers of sulphur, on which we pour a few gallons 

 of boiling water, covering it up for an hour, when 

 we stir it, till the whole of the sulphur has fallen to 

 the bottom. After settling, we pour off the water 

 for use, putting about a quart of it to the gallon for 

 syringing. A recent writer says, he uses one ounce 

 of nitre to one gallon of water, with which he 

 syringes the plants once in ten days, and finds it an 

 effectual cure. 



