Commercial and scientific notes on essential oils. 31 



ester content and defective solubility, most of the products now dealt with showed 

 almost normal constants: The specific gravity is generally in proportion with the ester 

 content (there are no exact indications), « -f- 12 to + 22° (on an average + 16 to + 17°), 

 soluble in 80 and 82.5 per cent, alcohol, ester content 31 to 36 per cent, for the oil 

 prepared in November/December and 36 to 39 per cent, for that obtained in January/ 

 February.. In some regions, the optical rotation of the oils was «-f-28 to 31°. 



It results from these constants, as the author remarks, that the effects of the 

 drought in summer 1920 is less noticeable in the quality of this year's product than 

 in that of last year's crop, but there is not a similar improvement in the yield. The 

 quantity expected is only 70 to 75000 kilos, i. e. less than half a normal crop. 



. With regard to the remarks which we connected with our discussion of Parrozani's 

 publication on bergamot oil of the 1920/21 crop (our last Bericht, p. 20), the author points 

 out that the constants established by him do not refer to the oils from fallings but 

 to those of ripe fruits. He further states that the samples have always been collected 

 by officials of the stations in the various producing districts, who also watched the 

 manufacturing process. The high rotatory power of the oils (« up to +37°) was 

 easily explained by that of the terpenes contained therein (a up to +72°). There 

 could not be any suspicion of adulteration with lemon or orange oils. Besides, his 

 figures were not intended to be a firm criterion for bergamot oils, but meant to show 

 that absolutely pure oils may sometimes have abnormal constants. 



Lemon Oil. — The downward tendency, of which we reported a year ago, lasted 

 until May, when such a low price level was reached that all concerned in the lemon 

 oil trade had to sustain the most serious losses. A fairly brisk demand which then 

 arose, sent the prices up a little, but only for a very short time, as the rumours of bad 

 prospects for the next crop proved to be exaggerated. Even a vivid demand, especially 

 from the United States, in the course of September, only led to a very moderate 

 hardening of the market, and although the October shipments were twice as large as 

 those of the previous month, no considerable rise was caused, as the imminent new 

 crop induced the producers to come forth with their stocks. The yield was normal 

 and taking into consideration the quantities still available of the old crop, it is thought 

 that a further decline of the prices may be predicted, as speculative attempts to bring 

 about a change have always only had a temporary effect. Only if the chief places 

 of consumption showed a much keener interest in the article, conditions might alter. 



Sicily supplies 88 per cent, of the total Italian lemon crop, whereas Calabria only 

 contributes 4, Campania 3.5, Apulia and Liguria 2 each and Sardinia 0.5 per cent. 1 ). 

 Most of the fruits are exported, only part being used for the manufacture of the 

 essential oil. In Palermo 90 per cent., in Siracusa 60 per cent, and in Catania 40 per cent, 

 of all the Citrus trees grown are lemon trees. The varieties cultivated most are those 

 producing oval fruits with a thin and smooth skin. Good lemons are supposed to 

 have pale yellow skin without any excrescences, sour juice and few pippins. In 

 Sicily, the following classification is made according to the time of gathering: — 

 A) Marzioli or Massani. They ripen in December, provided that favourable weather 

 immediately after the normal crop, i. e. in March, produces another bloom. B) Lemons. 

 They are the fruits of the normal bloom in April and May, ripening from December 

 to February and being collected during these months. C) Biancucci or Bianchetti, also 



J ) H. C. Holtz, Chem. Weekhlad 18 (1921), 108. 



