But, in any case, this sudden change of condition exposes the slaves to dangerous diseases. Moreover, melancholy seizes them, especially if they fear to be sold to stranger Arabs. They are persuaded that these Arabs are in want of meat, and come and buy them for food, and to use their brains for soap, and their blood for dyeing garments red. This belief is deeply implanted in the minds of all the slaves, and the Forians take advantage of it to reduce the indocile by fear. It is sufficient to threaten to sell them to the Jellabs to bring them to a sense of duty. The slaves do not get quit of their fear until they have been some time in the hands of the Arabs; but, during the whole length of the journey, they remain in continual terror. If we add to this cause the excessive fatigue of the march, the extremes of heat and cold in the deserts, it will not appear surprising that they die by thousands on the way. Only the very strong or the very fortunate reach as far as Egypt. I have seen Jellabs leave Wadaï with a hundred slaves, and lose them all by cold; and others have been deprived of still greater numbers by heat and thirst; whilst others, again, out of a single flock, find not one wanting. All this depends on the will of the Most High. Our holy law permits the sale and exportation of slaves, but on the express condition that we should act with the fear of God before our eyes; which sentiment, indeed, should be the guide of all our actions. The reasons by which slavery is justified are these:— God has commanded his Prophet, the Prophet of Islam, to announce the Divine law to men, to call them to believe in the true God, and to employ the force of arms to constrain unbelievers to embrace the true faith. According to the Divine word itself, war is the legitimate and holy means to bring men under the yoke of religion; for as soon as the infidels feel the arms of Islam, and see their power humiliated, and their families led away into slavery, they will desire to enter into the right way, in order to preserve their persons and their goods. If they resist, and are obstinate in their unbelief, it is necessary to march in arms against them. However, before resorting to this extreme means, we must invite them to submit to the law of Islam, and warn them many times on the misfortunes they will bring upon themselves by their incredulity.