The competition which arose through the processes of Haarmann and Reimer of Holzminden and G. de Laire of Paris, whose products owing to patent rights had controlled the market from the commencement, produced a steady decrease in the price of vanillin. The following table drawn up by J. Rouché[153] shows the revolution in price which has occurred in this article and how, in the course of time, a small business with large profits has been transformed into a large business with small profits. ~The variation in the price of vanillin~: Marks per Kilo. =====+======+======+======+======+======+======+====== 1876 | 1877 | 1878 | 1879 | 1881 | 1882 | 1884 | 1885 =====+======+======+======+======+======+======+====== 7000 | 4000 | 2400 | 1600 | 1600 | 1600 | 900 | 900 +======+======+======+======+======+======+===== | 1886 | 1888 | 1890 | 1892 | 1893 | 1895 | 1897 +======+======+======+======+======+======+===== | 700 | 700 | 700 | 700 | 700 | 560 | 108 The chemical formula of vanillin is C_{6}H_{3}(OCH_{3}) (OH)CHO; it melts between 82-83 ° C. and sublimes at 120 ° C. The colourless four-sided crystals have a strong vanilla odour and taste, are difficultly soluble in cold water, easily in hot water and very readily soluble in alcohol. Vanillin is much adulterated. Cumarin, the aromatic principle of the melitot (~meliotus officinalis~) and of tonquin beans etc., can be prepared cheaply and it is fraudulently used in large or small quantity to imitate the vanillin aroma. A sample of vanillin bought in Switzerland was found by Hefelmann[154] to contain 26 percent of antifebrin. The American “vanilla crystals” consist of a mixture of vanillin and antifebrin, or vanillin, cumarin and benzoic acid; latterly that article is stated to consist only of cumarin, antifebrin and sugar.