"Fourcroy, Vauquelin, Deyeux, Seguin, Proust, Jacquin, and Hermbstadt, between 1780 and 1790, in various interesting series of experiments, distinguished between different secondary elements of vegetable matter, particularly extract, , gums, and resinous substances; and investigations of this kind have been pursued with great success by Hatchett, Pearson, Shraeder, Chenevix, Gehlen, Thomson, Thenard, Chevreul, Kind, Brande, Bostock and Duncan. The chemistry of animal substances has received great elucidations from several of the same enquirers; and Berzelius has examined most of their results, and has added several new ones, in a comprehensive work expressly devoted to the subject, published in 1808."