in Extra-Tropical Countries. 



329 



the calyx is separated and rejected; the remaining portions of the 

 flowers are then subjected to aqueous distillation, and the saturated 

 rose-water so obtained is repeatedly used for renewed distillation, when 

 on any cold place the oil separates from the overcharged water and 

 floats on the surface, whence it can be collected after refrigeration by 

 fine birds' feathers. Rose-oil consists of a hydro-carbon stearopten, 

 which is scentless, and an elaeopten, which is the fragrant principle. 

 But some other methods exist for producing the oil; for instance, it 

 may be got by distilling the rosebuds without water at the heat of a 

 salt water bath, or by merely passing steam through the still. The 

 odor may also be withdrawn by alcoholic distillation from the roses, 

 or be extracted by the " enfleurage " process. The latter is effected 

 by placing the flowers, collected while the weather is warm, into 

 shallow frames covered with a glass-plate, on the inner side of which 

 a pure fatty substance has been thinly spread. The scent of the 

 flowers is absorbed by the adipose or oleous substance, though the 

 blossoms do not come in direct contact with it; fresh flowers are sup- 

 plied daily for weeks. The scent is finally withdrawn from its matrix 

 by maceration with pure alcohol. Purified eucalyptus-oil can be 

 used for diluting rose-oil, when it is required for the preparation of 

 scented soap. The essential oil of orange-peel might similarly be 

 employed as a vehicle. 



Rosa Damascena, Miller. 



Orient. Allied to the preceding species, and also largely used for 

 the production of essential oil of roses. The annual time of flower- 

 ing extends over several months. 



Rosa Gallica, Linn. (R. provincialis, Miller.) 



The French or Dutch Rose. Middle and Southern Europe, 

 Orient. Hardy to lat. 70 in Norway. The intensely colored buds 

 of this species are particularly chosen for drying. These however 

 may be got also from other kinds of roses. 



Rosa Indica, Linne". (R. Sinica, L.; R. Chinensis, Jacquin.) 



China, thence brought to India. The " Hybrid Perpetuals " are 

 largely traceable to this plant. Flowering time of long duration 

 annually. Some roses of the sweetest scent are derived from this 

 species. R. fragrans (Redoute), the Tea-Rose, is a variety. The 

 Noisette Rose is a cross of this and R. moschata. 



Rosa Isevigata, Michaux. (fi. Siniea, Murray, non Linne.) 



The Cherokee-Rose. China and Japan-. Considered one of the 

 best hedge-roses, and for that purpose much employed in North- 

 America. It serves well also for bowers. Allied to the foregoing 

 species. ^Rosa rugosa (Thunberg) of Japan, a large-fruited and 

 large-leaved rose, is exceedingly well adapted for garden-hedges also. 



moschata, Miller.* 



North-Africa and South-Asia, ascending the Indian mountains to 

 11,000 feet. Blooming all the year round in warm climes, but more 



Y 2 



