The gum is nothing else than the superabundant parts of the sap of this tree, which sap being too small in quantity, and drawn rapidly up by the heat of the sun, swells the fibres of the tree, bursts the imperceptible coats which surround it, and make a passage through the pores of the bark. This never happens when the tree only has the necessary quantity of sap for its preservation and growth; and then, if gum be wished for, it is necessary to use violence, and gain it from the nutriment of the tree by means of incision. This practice affords some produce, but cannot be executed without the loss of a large portion of the gum that escapes through these incisions, which the sap always endeavours to heal. Two gum harvests are made every year: the first, which is the most abundant, takes place in December: the knobs are then larger, cleaner, and drier. This harvest is the best, because the rains, which have just ceased, have moistened the earth, which has, in consequence, afforded a more abundant sap to the trees; and this the heat of the sun has had time to consolidate, though without drying it. The second harvest is made in March; but this affords less, and the produce is of an inferior quality, because the heat is then too violent, and it is necessary to make incisions before the gum can be obtained. Before the Senegal gum was known, that from Arabia furnished the whole consumption of Europe; but since this discovery the former has superseded the latter, and the Arabian gum is no longer to be seen: the little, however, which does come to us is derived from the Levant by the Provencals. They are in the habit of boasting of its properties as far beyond those of the Senegal gum; but several experiments have proved, that one is as good as the other, and may be employed for the same purposes. Besides the usual application of it in manufactures and medicine, we have a way of depriving it of its natural faintness; and, in several towns in France, they make it into excellent preserves. The Moors and Negroes are very fond of eating it in its crude state. The regular consumption of this gum in Europe is estimated at 1000 tons of 2000 lbs. each. The India Company formerly imported, every year, 1200 Moorish quintals (the quintal is reckoned equal to 900 lbs. French.) At present our trade is about 1,500,000 lbs.; and we might extend it to 2,000,000, without the concurrence of the English at Portendick.