The season when opportunity is found for putting the iron-works in motion is after the harvest has been housed and the rains are over. Already, in a previous chapter,[32] iron-work, as produced by the Dyoor, has been noticed, but the Bongo have a system considerably more advanced, which appears worthy of a brief description. Their smelting apparatus is an erection of clay, generally about five feet in height, containing in its interior three distinct compartments.[33] These are all of the same size, that in the middle being filled with alternate layers of fuel and ore. This centre chamber is separated from the lower by means of a kind of frame resting on a circular projection; and it is divided from the chamber above by a narrow neck of communication. The highest and lowest of the divisions are used for fuel only. Round the base of the inferior chamber there are four holes, into which the “tewels” or pokers are introduced, and to which bellows are applied to increase the intensity of the combustion; there is a fifth hole, which can be stopped with clay as often as may be desired, and which serves to allow the metal to be raked out after it has trickled down into the cavity below the frame. [Illustration] The most important of the iron productions are designed for the trade that the Bongo carry on with the tribes that dwell in the north, and which some time since was very active. The raw iron is exhibited in three separate shapes: one is named “mahee,” being spear-heads of one or two feet long, corresponding exactly with what has been mentioned as common with the Dyoor; the second is known as “loggoh kullutty,” and is simply a lot of black, ill-formed spades; the third is called distinctively “loggoh,” consisting of regular spades, which, under the market appellation of “melot,” have a wide sale everywhere along the course of the Upper Nile. [Illustration: Iron money. Loggoh Kullutty. Loggoh melot.] [Sidenote: BONGO MONEY.]