The Dutch tonka bean is 1.18 to 1.57 inches long, 0.39 to O.59 inch wide, and O.27 to O.43 inch thick. It is generally slightly curved, provided under the point with the hilum, and covered with a thin, fragile, brown-black or black skin of a fatty lustre, upon which small crystals of cumarin are generally found, so that it appears coated, especially in the wrinkles, with a whitish dust. The kernel consists of two yellow-brownish oleiferous catyledons, between which layers of cumarin are generally found. The odor is agreeable, resembling that of melilot, and the taste aromatic bitter. Dutch tonka beans contain fat, sugar, malic acid, and malate of lime; further, starch, gum, and 1 to 5 per cent. of cumarin (C_{9}H_{6}O_{2}). The English tonka beans are smaller, white-yellowish inside, nearly black outside, and of inferior quality to the Dutch beans. From tonka beans, cumarin may be obtained by two different methods. One method consists in repeatedly extracting the bruised beans with spirit of wine, distilling the latter off from the extract, and mixing the residue with cold water, whereby cumarin contaminated with fat is precipitated. To remove the fat, bring the whole to the boiling point, filter the hot solution through a moist filter upon which the fat is retained, and allow to cool, whereby the greater portion of the cumarin crystallizes out; the remaining small portion is obtained by evaporating the mother-lye. According to the other method, the bruised tonka beans are distilled with water. After 24 hours the greater portion of the cumarin separates in a crystalline form. The residue remaining in solution can be withdrawn from the water by shaking with petroleum-ether and subsequent evaporation of the solvent. From one pound of good tonka beans, up to 4 drachms of cumarin may be obtained. Cumarin is sometimes also obtained by purifying by recrystallization of the débris found in the original boxes of tonka beans, which chiefly consists of cumarin. Perkin has recently succeeded in artificially preparing cumarin from salicylic acid. By boiling the sodium salt of the latter in acetic anhydride for a few minutes and then pouring into water, an oil-like body is separated, whilst sodium acetate passes into solution. The former is a mixture of acetic anhydride, salicylic acid and cumarin; in distilling, the latter passes over last (at 554° F.), and congeals in the receiver to a crystalline mass. Cumarin is now synthetically prepared by several firms, that brought into the market by Schimmel & Co., of Leipsic, especially being of excellent quality. Although artificial cumarin is considerably lower in price than that obtained from tonka beans, most perfumers still prefer the extract from tonka beans prepared by themselves. There is, however, no good reason for this, since a change in the respective receipts for perfumes presents no difficulties, 8.46 drachms of cumarin corresponding to 2.2 lbs. of best tonka beans.