"If the hives are to be transferred from one place to another it is necessary to choose a fit time to make the move and a suitable place to receive them. As to time, spring is preferable to winter because in winter they have difficulty in adjusting themselves to a new location and so often run away, as they do also if you move them from a good location to a place where proper pasture is not available. Nor is a transfer from one hive to another in the same place to be undertaken carelessly, but that to which the bees are to be transferred should be rubbed with bee balm, which will serve as a bait for them, and some pieces of honey comb should be placed in it, not far from the entrances, for fear that the bees might run away if they found the larder of their new home empty. "Menecrates says that bees contract a malady of the bowels from their first spring pasture on the blossoms of the almond and the cornel cherry and are cured by giving them urine to drink.[214] "That gummy substance which the bees use, chiefly in summer to construct a sort of curtain between the entrance and the hive, is called _propolis_, and by the same name is used by physicians in making plasters: by reason of which use it sells in the Via Sacra for more than honey itself. That substance which is called _erithacen_, and is used to glue the cells together, is different from both honey and _propolis_: it is supposed to have a quality of attraction for bees and is accordingly mixed with bee balm and smeared on the branch or other place on which it is desired to have a swarm light. The comb is made of wax and is multicellular, each cell in it having six sides or as many as nature has given the bee feet. It is said that bees do not gather from the same plants all the materials which enter in these four substances which they manufacture, namely: propolis, erithacen, wax and honey. Thus from the pomegranate and the asparagus they gather food alone, wax from the olive tree, honey from the fig, but not of good quality: other plants like the bean, the bee balm, the gourd and the cabbage serve a double purpose and yield both wax and food: while the apple and the wild pear serve a similar double purpose but for food and honey and the poppy again for wax and honey. "Others again provide material for three purposes, food, honey and wax, such as the almond and the charlock.[215] In like manner there are flowers from each of which they derive a different one of these substances, and others from which they derive several of them: while they make distinctions in respect of plants according to the quality of the product they yield,--or rather the plants make the distinction for them--as with respect to honey, some yield liquid honey, like the skirwort,[216] and others thick honey like the rosemary. So again honey of insipid flavour is made from the fig, good honey from clover, and the best of all from thyme.