Scientific and other notes on essential oils. 



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one may perhaps safely count upon a yield of 300 okas per ddnum or 4200 kilos per hectare. 

 In 1916, the crop was passable, but the yield in oil especially bad, owing to the drought. 

 Whilst in favourable weather 10 kilos of red Kazanlik roses yield 1 miskal = 4.811 grams 

 of oil, up to 20 kilos are required in bad years. White Kazanlik roses are supposed 







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to yield in favourable years up to 1000 okas of flowers per donum, i. e. about 11000 kilos 

 per hectare. As an average yield, 350 okas per donum was indicated to me at Brussa, 

 for white Kazanlik roses. In favourable years, 1 miskal of oil is obtained from 18 kilos 

 of flowers, whereas in bad ones about 23 kilos are required. The yield of the indige- 

 nous "hafis" rose, cultivated in certain parts of the vilayet of Brussa, is said to arrive 



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