— 5o — 



Lemon oil. 0450 0,856 to 0,861. 



The rotation varies according to the producing district and the 

 degree of ripeness of the fruit; generally speaking it ranges from 

 -\- 58 to -f- 66° (20 C). The fruit known as Bastardoni yields 

 an oil of which the rotation occasionally falls below -j- 5 6°. 



Evaporation residue 2 to 3,5%; in the case of oil pressed by 

 mechanical means up to 5 °/ . 



The citral content varies, according to the methods employed, 

 from 4 to 7,5 %. 



Beginning of boiling at 175 . 



Bergamot oil. di 5 o 0,880 to 0,887; U P to a certain degree the 

 sp. gr. is in direct proportion to the ester content. «d -[- 7 to -{- 25 ; 

 usually between -|- 10 and -j-20°. 



Acid content (calculated as acetic acid) 0,15 to 0,2 °/ ; in the case 

 of old oils up to 4 °/ . 



Ester content 33 to 44 °/ . 

 • Evaporation residue 5 to 6 °/ . 



Solubility : Pure bergamot oil dissolves in half its volume of 90 p. c. 

 alcohol, most samples are soluble in their own vol. of 80 per cent, 

 alcohol, the last-named degree of solubility indicates an oil of good 

 quality 1 ). 



Beginning of boiling at 180 (normal press.) equal to 72 (20 mm. 

 press.). 



In order to detect the presence of French or American oil of 

 turpentine, Berte and Romeo recommend that the first two fractions 

 of 5 cc. each of 30 cc. oil be distilled off under reduced pressure, 

 and that they be then tested in order to ascertain whether the first 

 fraction has a higher rotatory power than the second. Further, the 

 mean rotation of the two fractions should bear a definite relation to 

 that of the original oil. This relation should alter with the rotation 

 of the oil, and a table is given (compare original report), setting 

 forth particulars under this head. 



The following bergamot oils are of inferior quality: 



a) The oil obtained from unripe windfalls (bergamottelld). This oil 

 is known as new di bergamotto. It has a rather unpleasant, pungent 

 odour, a dark colour and a high specific gravity; d^o 0,890 to 0,896. 



Ester content between 20 and 35%. 



b) Distilled oil. This is obtained from the dregs (feccie di berga- 

 motto) by distillation with water vapour. It is colourless or yellowish; 

 d^o about 0,865 ; ester content 3 to 6 °/ . 



1 ) Of the many oils of the highest quality which we have examined in our 

 laboratories, the minority were soluble in 1 vol. of 80 °/ alcohol. Compare Report 

 November 1908, 60. 



