The Work done in Algiers
Have a colt of three of four years and feed it on rye barley and straw cut in the same way as that which they use to feed horses in Spain. Let it drink water from a good fountain or river water. I do not know if it would be good sometimes to let him drink the water of sulfur springs, and to sometimes give him fenugreek or other hot foods, for the intention of the worker is to use the heat of his manure, and the climate here is cooler than that of Algiers. Keep it in a warm place and use it and make sure it loses none of its manure or urine, of which you will make a mass or two so that while one cools the other will keep its heat and be suitable to continue. Also have a large flask as thick as possible, one finger thick if it can be so made, and with a capacity of one pitcher or clay jug, and around the feast of St John place a dozen and a half chicken eggs, that is to say, the egg without the egg white and the germ. Others say sixty yolks. And with this dozen and a half of chicken egg yolks put one half ounce (others say sixty eggs and a half pound) of female silk worm eggs. And after carefully luting the flask (I do not know if air will be needed for the generation) and bury it in the heat of the manure up to the neck, and leave it there until several worms are engendered and then remove the flask and do not bury it in the manure anymore. But put it on the hot layer of the manure until all the worms are eaten and consume one another by shriveling and stirring, and only one remains. Once this has happened, you must lure it at regular intervals, day and night, with the assistance of two men, who will care for it in shifts, and you will lure it with an egg yolk covered in gold leaf or with a liquid yolk into which the gold leaf has been incorporated. And be careful that it does not miss such fodder (some say one egg yolk per hour, others say three, but the thing itself will demonstrate the practice). So nourished in this way it will grow in two month or seven weeks and will become like a serpent, one span and four fingers long, and one pound in weight, and as the wings will begin to develop, you must kill it, doing so with a charcoal fire in a ring around the bottle one span away from it, and at that time lute the bottle well so that it does not exhale.
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