— no 



the properties and derivatives of which he discusses. This small mono- 

 graph, which has been written by a practicist, should be of special 

 interest to those practically engaged in the business. 



The Commercial Products of India (London, John Murray, 1908) 

 is the title of a book by Sir George Watt which, as the author 

 himself states, consists of a synopsis of his own voluminous work 

 Dictio?iary of the Economic Products of India. It goes without saying 

 that in this synopsis regard has been taken to recent research. The 

 volume, which contains 11 89 pages, carries out its purpose of giving, 

 in a compressed and concise form, the most important details on the 

 economic products of India. It will probably be welcomed by all who 

 wish to acquaint themselves rapidly with what is most worth knowing 

 on this subject. 



We are glad to seize this occasion of expressing our best thanks 

 to the author for kindly presenting us with a copy of the book. 



A further series has appeared of J. W. Br and el's 1 ) discussions 

 on the investigations of essential oils published in the years 1901 to 

 1903, to which work we have repeatedly referred in the past 2 ). 



Analytical. 



The method for the determination of the citral content in oil of 

 lemon by the use of hydroxylamine, which was recommended by 

 J. Walt her 3 ) and discussed by us in detail at the time 4 ), has now 

 been published, in a modified form, by A. H. Bennett 5 ). This 

 author, uses potash liquor instead of bicarbonate of sodium for averting 

 the evolution of carbonic acid and the loss of hydroxylamine which 

 may result therefrom. The quantity of alcoholic potash used by him is 

 sufficient to liberate from its hydrochloric salt an excess of hydroxyl- 

 amine in proportion to the citral present, so that a residue of 

 unconverted hydrochloride is left. Bennett proceeds as follows: He 

 dilutes a mixture of 20 cc. of lemon oil and 20 cc. alcoholic (80 per 

 cent, alcohol) 1 / 2 normal solution of hydrochloride of hydroxylamine 

 with 8 cc. of alcoholic normal alcoholic potash and 20 cc. strong alcohol, 

 free from aldehyde, and boils for half an hour with reflux- condenser. 

 After cooling, the mixture is diluted with 250 cc. water, part of which 

 is used for washing down the reflux-condenser, and the hydrochloric 

 acid which is still present in the form of hydrochloride of hydroxylamine 



x ) Pharm. Review 26 (1908), 371. 



2 ) Report April 1908, 168; November 1908, 155. 



3 ) Pharm. Zentralh. 40 (1899), 621; 41 (1900), 614. 



4 ) Report April 1900, 22. 



5 ) The Analyst 34 (1909), 14. Quoted from Chem. Zentralbl. 1909, I. 593. 



